阅读说明：本技术 倍压调整电路 (Voltage doubling regulating circuit ) 是由 何丹丹 于 2021-08-10 设计创作，主要内容包括：本发明公开了一种倍压调整电路,包括电源输入端、电源输出端、输出控制电路、倍压电路、电压检测电路和控制模块。输出控制电路的输入端与电源输入端连接,第一输出端与电源输出端连接。倍压电路的输入端与所述输出控制电路的第二输出端连接,输出端与电源输出端连接,倍压电路用于倍压输出电源电压。电压检测电路的输入端与电源输入端连接,检测电源输入端输入的交流电源电压并输出检测电压信号。控制模块与输出控制电路的受控端和电压检测电路的输出端分别连接,控制输出控制电路将交流电源电压进行整流后输出至倍压电路或电源输出端。本发明通过设置设定电压值,由控制模块控制开关电路,进而控制倍压电路,实现自动对输入的电源电压进行倍压。(The invention discloses a voltage-multiplying adjusting circuit which comprises a power supply input end, a power supply output end, an output control circuit, a voltage-multiplying circuit, a voltage detection circuit and a control module. The input end of the output control circuit is connected with the power input end, and the first output end is connected with the power output end. The input end of the voltage doubling circuit is connected with the second output end of the output control circuit, the output end of the voltage doubling circuit is connected with the power output end, and the voltage doubling circuit is used for outputting power voltage in a voltage doubling mode. The input end of the voltage detection circuit is connected with the power input end, detects the alternating current power supply voltage input by the power input end and outputs a detection voltage signal. The control module is connected with the controlled end of the output control circuit and the output end of the voltage detection circuit respectively, and controls the output control circuit to rectify the alternating current power supply voltage and output the rectified alternating current power supply voltage to the voltage doubling circuit or the power supply output end. According to the invention, the set voltage value is set, the control module controls the switch circuit, and then the voltage doubling circuit is controlled, so that the input power supply voltage is automatically doubled.)

1. A voltage-doubling adjustment circuit, comprising:

the power supply comprises a power supply input end and a power supply output end, wherein the power supply input end is used for inputting alternating-current power supply voltage;

the output control circuit is provided with a controlled end, an input end, a first output end and a second output end, the input end of the output control circuit is connected with the power supply input end, and the first output end is connected with the power supply output end;

the voltage doubling circuit is provided with an input end and an output end, the input end of the voltage doubling circuit is connected with the second output end of the output control circuit, the output end of the voltage doubling circuit is connected with the power supply output end, and the voltage doubling circuit is used for receiving the rectified power supply voltage and outputting the voltage-doubled power supply voltage;

the voltage detection circuit is provided with an input end and an output end, the input end of the voltage detection circuit is connected with the power supply input end, and the voltage detection circuit is used for detecting the size of the alternating-current power supply voltage input by the power supply input end and outputting a corresponding detection voltage signal;

the control module is respectively connected with the controlled end of the output control circuit and the output end of the voltage detection circuit;

the control module is used for controlling the output control circuit to rectify the alternating current power supply voltage input by the power supply input end and output the rectified alternating current power supply voltage to the voltage doubling circuit when the voltage value corresponding to the detection voltage signal is smaller than a set voltage value, and controlling the output control circuit to rectify the alternating current power supply voltage input by the power supply input end and output the rectified alternating current power supply voltage to the power supply output end when the voltage value corresponding to the detection voltage signal is larger than or equal to the set voltage value.

2. The voltage-doubling regulation circuit of claim 1, wherein the voltage-doubling circuit comprises a first capacitor and a second capacitor;

the first end of the first capacitor is connected with the first output end of the output control circuit, and the second end of the first capacitor is connected with the first end of the second capacitor;

the first end of the second capacitor is further connected with the second output end of the output control circuit, and the second end of the second capacitor is used for grounding.

3. The voltage-doubling regulation circuit of claim 2, wherein the output control circuit comprises:

the rectifying circuit is provided with a first end, a second end, a third end and a fourth end, the first end of the rectifying circuit is connected with a live wire input end of the power input end, the second end of the rectifying circuit is connected with a zero line input end of the power input end, the third end of the rectifying circuit is connected with the first end of the first capacitor, the fourth end of the rectifying circuit is connected with the second end of the second capacitor, and the rectifying circuit is used for rectifying and outputting input alternating current power supply voltage;

the controlled end of the switch circuit is connected with the control module, the input end of the switch circuit is connected with the zero line input end of the power supply input end, and the output end of the switch circuit is connected with both the second end of the first capacitor and the first end of the second capacitor;

the switch circuit is used for switching on a path between the power input end and the voltage doubling circuit under the control of the control module when the voltage value corresponding to the detection voltage signal is smaller than a set voltage value, and switching off the path between the zero line input end of the power input end and the voltage doubling circuit under the control of the control module when the voltage value corresponding to the detection voltage signal is larger than or equal to the set voltage value.

4. The voltage-doubling regulation circuit of claim 3, wherein the switching circuit comprises:

the controlled end of the first switch circuit is connected with the control module, and the input end of the first switch circuit is connected with the zero line input end of the power supply input end;

and the controlled end of the second switch circuit is connected with the control module, the input end of the second switch circuit is connected with the output end of the first switch circuit, and the output end of the second switch circuit is connected with the second end of the first capacitor and the first end of the second capacitor.

5. The voltage-doubling regulation circuit of claim 3 wherein the voltage detection circuit comprises a first resistor and a second resistor;

the input end of the first resistor is connected with the live wire input end of the power supply input end, and the output end of the first resistor is connected with the control module;

the input end of the second resistor is connected with the output end of the first switch circuit, and the output end of the second resistor is connected with the control module.

6. The voltage-doubling regulating circuit according to claim 5, wherein in a first half-wave of each ac power cycle, the control module is configured to control the first switch circuit and the second switch circuit to be turned on when the voltage value corresponding to the detection voltage signal is smaller than a set voltage value, so as to switch on a path between a zero line input end of the power input end and the first capacitor, so that the voltage-doubling circuit doubles the rectified power voltage and outputs the doubled rectified power voltage to the power output end;

in a first half-wave of each alternating current power supply period, the control module is configured to control the first switch circuit to be turned on when the voltage value corresponding to the detection voltage signal is greater than or equal to a set voltage value, so that the voltage detection circuit detects the magnitude of the alternating current power supply voltage input by the power supply input end, and control the second switch circuit to be turned off, so as to break a path between a zero line input end of the power supply input end and the first capacitor, and output the rectified power supply voltage to the power supply output end; the control module is further used for acquiring a detection voltage signal of the voltage detection circuit and recording a time period when a voltage value corresponding to the detection voltage signal is greater than or equal to a set voltage value;

in a second half wave of each alternating current power supply period, the control module is configured to control the first switch circuit and the second switch circuit to be turned on when the voltage value corresponding to the detection voltage signal is smaller than a set voltage value, so as to switch on a path between a zero line input end of the power supply input end and the second capacitor, so that the voltage doubling circuit doubles the rectified power supply voltage and outputs the doubled power supply voltage to the power supply output end;

in a second half-wave of each alternating current power supply cycle, the control module is further configured to control the first switch circuit and the second switch circuit to be disconnected in a time period corresponding to the first half-wave, so as to disconnect a path between a zero line input end of the power supply input end and the second capacitor, and output the rectified power supply voltage to the power supply output end.

7. The voltage-doubling regulation circuit of claim 1 further comprising a first power supply circuit;

the input end of the first power supply circuit is used for being connected with the power supply input end, the output end of the first power supply circuit is connected with the control module, and the first power supply circuit is used for supplying power to the control module when an alternating current power supply is initially accessed.

8. The voltage-doubling regulation circuit of claim 7 wherein the first power supply circuit comprises a third resistor, a third capacitor, and a fifth diode;

the input end of the third resistor is used for being connected with the power supply input end, and the output end of the third resistor is connected with the input end of the control device;

the first end of the third capacitor is connected with the output end of the third resistor, and the second end of the third capacitor is grounded;

and the anode of the fifth diode is connected with the output end of the third resistor, and the cathode of the fifth diode is grounded.

9. The voltage-doubling regulation circuit of claim 1 further comprising a second power supply circuit;

the input end of the second power supply circuit is used for accessing power supply voltage, the output end of the second power supply circuit is connected with the control module, and the second power supply circuit is used for supplying power to the control module when the control module works.

10. The voltage-doubling regulation circuit of claim 9 wherein the second power supply circuit comprises a fourth resistor and a sixth diode;

the cathode of the sixth diode is used for being connected with a power supply voltage, the anode of the sixth diode is connected with the input end of the fourth resistor, and the output end of the fourth resistor is connected with the control device.

Technical Field

The invention relates to the field of power electronics, in particular to a voltage doubling adjusting circuit.

Background

Voltage doubler rectifier circuits are often used where high voltages and low currents are required. The voltage-doubling rectification can be used for rectifying a lower alternating voltage into a higher direct voltage by using a rectifying diode and a capacitor with higher voltage resistance. The voltage-doubling rectifying circuit is generally divided into a double-voltage, triple-voltage and multiple-voltage rectifying circuits according to the output voltage which is multiple of the input voltage.

The traditional voltage doubling circuit adopts a mechanical switch, and the voltage doubling is selected by manually switching the switch according to the voltage of the input mains supply, so that the voltage doubling switching speed is low. The manual operation is improper, and the voltage doubling circuit can carry out voltage doubling when the voltage doubling is not needed, so that high voltage is generated, and a rear-stage circuit is damaged. And because the difference of the voltage-multiplying capacitors causes different capacitance voltage drops, a balance resistor needs to be connected in parallel to balance the voltage of the voltage-multiplying circuit. The parallel balance resistor increases loss and has potential safety hazard.

Disclosure of Invention

The present invention provides a voltage doubling regulating circuit, which aims to automatically perform voltage doubling regulation on the voltage of the input end of a power supply.

To achieve the above object, the present invention provides a voltage-doubling adjusting circuit, including:

the power supply comprises a power supply input end and a power supply output end, wherein the power supply input end is used for inputting alternating-current power supply voltage;

the output control circuit is provided with a controlled end, an input end, a first output end and a second output end, the input end of the output control circuit is connected with the power supply input end, and the first output end is connected with the power supply output end;

the voltage doubling circuit is provided with an input end and an output end, the input end of the voltage doubling circuit is connected with the second output end of the output control circuit, the output end of the voltage doubling circuit is connected with the power supply output end, and the voltage doubling circuit is used for receiving the rectified power supply voltage and outputting the voltage-doubled power supply voltage;

the voltage detection circuit is provided with an input end and an output end, the input end of the voltage detection circuit is connected with the power supply input end, and the voltage detection circuit is used for detecting the size of the alternating-current power supply voltage input by the power supply input end and outputting a corresponding detection voltage signal;

the control module is respectively connected with the controlled end of the output control circuit and the output end of the voltage detection circuit;

the control module is used for controlling the output control circuit to rectify the alternating current power supply voltage input by the power supply input end and output the rectified alternating current power supply voltage to the voltage doubling circuit when the voltage value corresponding to the detection voltage signal is smaller than a set voltage value, and controlling the output control circuit to rectify the alternating current power supply voltage input by the power supply input end and output the rectified alternating current power supply voltage to the power supply output end when the voltage value corresponding to the detection voltage signal is larger than or equal to the set voltage value.

In one embodiment, the voltage doubling circuit comprises a first capacitor and a second capacitor;

the first end of the first capacitor is connected with the first output end of the output control circuit, and the second end of the first capacitor is connected with the first end of the second capacitor;

the first end of the second capacitor is further connected with the second output end of the output control circuit, and the second end of the second capacitor is used for grounding.

In one embodiment, the output control circuit includes:

the rectifying circuit is provided with a first end, a second end, a third end and a fourth end, the first end of the rectifying circuit is connected with a live wire input end of the power input end, the second end of the rectifying circuit is connected with a zero line input end of the power input end, the third end of the rectifying circuit is connected with the first end of the first capacitor, the fourth end of the rectifying circuit is connected with the second end of the second capacitor, and the rectifying circuit is used for rectifying and outputting input alternating current power supply voltage;

the controlled end of the switch circuit is connected with the control module, the input end of the switch circuit is connected with the zero line input end of the power supply input end, and the output end of the switch circuit is connected with both the second end of the first capacitor and the first end of the second capacitor;

the switch circuit is used for switching on a path between the power input end and the voltage doubling circuit under the control of the control module when the voltage value corresponding to the detection voltage signal is smaller than a set voltage value, and switching off the path between the zero line input end of the power input end and the voltage doubling circuit under the control of the control module when the voltage value corresponding to the detection voltage signal is larger than or equal to the set voltage value.

In one embodiment, the switching circuit includes:

the controlled end of the first switch circuit is connected with the control module, and the input end of the first switch circuit is connected with the zero line input end of the power supply input end;

and the controlled end of the second switch circuit is connected with the control module, the input end of the second switch circuit is connected with the output end of the first switch circuit, and the output end of the second switch circuit is connected with the second end of the first capacitor and the first end of the second capacitor.

In one embodiment, the voltage detection circuit includes a first resistor and a second resistor;

the input end of the first resistor is connected with the live wire input end of the power supply input end, and the output end of the first resistor is connected with the control module;

the input end of the second resistor is connected with the output end of the first switch circuit, and the output end of the second resistor is connected with the control module.

In an embodiment, in a first half-wave of each ac power cycle, the control module is configured to control the first switch circuit and the second switch circuit to be turned on when a voltage value corresponding to the detection voltage signal is smaller than a set voltage value, so as to switch on a path between a zero line input end of the power input end and the first capacitor, so that the voltage doubling circuit doubles the rectified power voltage and outputs the doubled rectified power voltage to the power output end;

in a first half-wave of each alternating current power supply period, the control module is configured to control the first switch circuit to be turned on when the voltage value corresponding to the detection voltage signal is greater than or equal to a set voltage value, so that the voltage detection circuit detects the magnitude of the alternating current power supply voltage input by the power supply input end, and control the second switch circuit to be turned off, so as to break a path between a zero line input end of the power supply input end and the first capacitor, and output the rectified power supply voltage to the power supply output end; the control module is further used for acquiring a detection voltage signal of the voltage detection circuit and recording a time period when a voltage value corresponding to the detection voltage signal is greater than or equal to a set voltage value;

in a second half wave of each alternating current power supply period, the control module is configured to control the first switch circuit and the second switch circuit to be turned on when the voltage value corresponding to the detection voltage signal is smaller than a set voltage value, so as to switch on a path between a zero line input end of the power supply input end and the second capacitor, so that the voltage doubling circuit doubles the rectified power supply voltage and outputs the doubled power supply voltage to the power supply output end;

in a second half-wave of each alternating current power supply cycle, the control module is further configured to control the first switch circuit and the second switch circuit to be disconnected in a time period corresponding to the first half-wave, so as to disconnect a path between a zero line input end of the power supply input end and the second capacitor, and output the rectified power supply voltage to the power supply output end.

In one embodiment, the voltage-doubling adjusting circuit further comprises a first power supply circuit;

the input end of the first power supply circuit is used for being connected with the power supply input end, the output end of the first power supply circuit is connected with the control module, and the first power supply circuit is used for supplying power to the control module when an alternating current power supply is initially accessed.

In one embodiment, the first power supply circuit includes a third resistor, a third capacitor, and a fifth diode;

the input end of the third resistor is used for being connected with the power supply input end, and the output end of the third resistor is connected with the input end of the control device;

the first end of the third capacitor is connected with the output end of the third resistor, and the second end of the third capacitor is grounded;

and the anode of the fifth diode is connected with the output end of the third resistor, and the cathode of the fifth diode is grounded.

In an embodiment, the voltage-doubling adjusting circuit further comprises a second power supply circuit;

the input end of the second power supply circuit is used for accessing power supply voltage, the output end of the second power supply circuit is connected with the control module, and the second power supply circuit is used for supplying power to the control module when the control module works.

In one embodiment, the second power supply circuit includes a fourth resistor and a sixth diode;

the cathode of the sixth diode is used for being connected with a power supply voltage, the anode of the sixth diode is connected with the input end of the fourth resistor, and the output end of the fourth resistor is connected with the control device.

The invention realizes automatic voltage doubling adjustment of the input power voltage by detecting the input alternating power voltage, doubling the rectified power voltage when the input alternating power voltage is smaller than a set voltage value, and directly outputting the rectified power voltage without doubling the rectified power voltage when the input alternating power voltage is larger than or equal to the set voltage value. By setting the set voltage value, the voltage value of the voltage doubling circuit is enabled to always follow the set voltage value, and voltage balance is achieved. The problem that the traditional voltage doubling circuit cannot automatically perform voltage doubling adjustment on the input power supply voltage is solved.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the structures shown in the drawings without creative efforts.

FIG. 1 is a schematic diagram of a conventional voltage doubling circuit;

FIG. 2 is a schematic diagram of a voltage-doubling regulating circuit according to an embodiment of the present invention;

FIG. 3 is a schematic diagram of a voltage-doubling regulating circuit according to an embodiment of the present invention;

FIG. 4 is a waveform diagram of the input AC power voltage variation within an AC power cycle according to one embodiment of the present invention;

FIG. 5 is a waveform diagram illustrating the variation of the input AC power voltage within the AC power cycle according to an embodiment of the present invention.

The implementation, functional features and advantages of the objects of the present invention will be further explained with reference to the accompanying drawings.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

It should be noted that all the directional indicators (such as up, down, left, right, front, and rear … …) in the embodiment of the present invention are only used to explain the relative position relationship between the components, the movement situation, etc. in a specific posture (as shown in the drawing), and if the specific posture is changed, the directional indicator is changed accordingly.

In addition, the descriptions related to "first", "second", etc. in the present invention are for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In addition, technical solutions between various embodiments may be combined with each other, but must be realized by a person skilled in the art, and when the technical solutions are contradictory or cannot be realized, such a combination should not be considered to exist, and is not within the protection scope of the present invention.

Referring to fig. 1, a conventional voltage doubling adjusting circuit employs a mechanical switch, and a worker manually turns on or off the mechanical switch according to the magnitude of an input ac power voltage, thereby controlling the connection state between a power input terminal and the voltage doubling circuit. When the input alternating-current power supply voltage is low voltage (for example, 90V-132V), a worker controls the mechanical switch to be closed, a path between the power supply input end and the voltage doubling circuit is switched on, and the voltage doubling circuit performs voltage doubling on the rectified power supply voltage, so that the voltage output by the voltage doubling adjusting circuit is twice of the rectified power supply voltage; when the input alternating current power supply voltage is high voltage (for example 185V-230V), an operator controls the mechanical switch to be switched off, a path between the power supply input end and the voltage doubling circuit is switched off, the voltage doubling circuit does not work, and the voltage output by the voltage doubling adjusting circuit is the rectified power supply voltage. However, in practical applications, there may be an operator's operational error, and when the input ac power voltage is a high voltage, the mechanical switch is controlled to close, so as to close the path between the power input terminal and the voltage doubling circuit, and the voltage doubling circuit doubles the rectified power voltage, so that the voltage output by the voltage doubling adjusting circuit is twice the rectified power voltage. The voltage doubling circuit outputs too high voltage to damage the subsequent circuit. And because of the difference of the voltage-multiplying capacitors, balancing resistors need to be connected in parallel at two ends of the voltage-multiplying capacitors, so that the circuit loss is increased, and potential safety hazards also exist.

Referring to fig. 2, to solve the above problem, the present invention provides a voltage doubling adjusting circuit, which includes a power input terminal 100, a power output terminal 200, an output control circuit 300, a voltage doubling circuit 400, a voltage detection circuit 500, and a control module 600.

The power input terminal 100 is used for inputting an ac power voltage.

The output control circuit 300 has a controlled terminal, an input terminal, a first output terminal and a second output terminal, the input terminal of the output control circuit 300 is connected to the power input terminal 100, and the first output terminal is connected to the power output terminal 200.

The voltage doubling circuit 400 has an input terminal and an output terminal, the input terminal of the voltage doubling circuit 400 is connected to the second output terminal of the output control circuit 300, the output terminal of the voltage doubling circuit 400 is connected to the power output terminal 200, and the voltage doubling circuit 400 is configured to receive the rectified power voltage and perform voltage doubling and then output the rectified power voltage.

The voltage detection circuit 500 has an input terminal and an output terminal, the input terminal of the voltage detection circuit 500 is connected to the power input terminal 100, and the voltage detection circuit 500 is configured to detect the magnitude of the ac power voltage input by the power input terminal 100 and output a corresponding detection voltage signal.

The control module 600 is connected to the controlled terminal of the output control circuit 300 and the output terminal of the voltage detection circuit 500, respectively.

The control module 600 is configured to control the output control circuit 300 to rectify the ac power voltage input from the power input terminal 100 and output the rectified ac power voltage to the voltage doubling circuit 400 when the voltage value corresponding to the detected voltage signal is smaller than the set voltage value, and control the output control circuit 300 to rectify the ac power voltage input from the power input terminal 100 and output the rectified ac power voltage to the power output terminal 200 when the voltage value corresponding to the detected voltage signal is greater than or equal to the set voltage value.

In the above embodiment, the control module 600 may adopt an FT61F020 chip.

The voltage detection circuit 500 detects the ac power voltage input from the power input terminal 100 and outputs a corresponding voltage detection signal to the control module 600, and the output control circuit 300 rectifies the input ac power voltage and converts the ac power voltage into a dc power voltage for the voltage doubling circuit 400 to perform voltage doubling.

When the voltage value corresponding to the detection voltage signal is smaller than the set voltage value, the output control circuit 300, under the control of the control module 600, switches on the path from the zero line input end of the power input end 100 to the voltage doubling circuit 400, and outputs the rectified power voltage to the voltage doubling circuit 400. The voltage doubling circuit 400 doubles the rectified power supply voltage so that the voltage output by the voltage doubling adjustment circuit is a multiple of the rectified power supply voltage.

When the voltage value corresponding to the detected voltage signal is greater than or equal to the set voltage value, the output control circuit 300, under the control of the control module 600, disconnects the path from the power input terminal 100 to the voltage doubling circuit 400, and outputs the rectified power voltage to the power output terminal 200, so that the voltage doubling adjusting circuit directly outputs the rectified power voltage.

The invention can automatically adjust the voltage doubling of the input power voltage by detecting the input alternating power voltage, doubling the rectified power voltage when the input alternating power voltage is smaller than a set voltage value, and directly outputting the rectified power voltage without doubling the rectified power voltage when the input alternating power voltage is larger than or equal to the set voltage value, thereby preventing the voltage doubling adjusting circuit from damaging a rear-stage circuit due to overhigh output voltage. By setting the set voltage value, the voltage value of the voltage doubling circuit is enabled to always follow the set voltage value, and voltage balance is achieved. The problem that the traditional voltage doubling circuit cannot automatically perform voltage doubling adjustment on the input power supply voltage is solved.

Referring to fig. 3, in an embodiment, the voltage doubling circuit 400 includes a first capacitor C1 and a second capacitor C2.

A first terminal of the first capacitor C1 is connected to a first output terminal of the output control circuit 300, and a second terminal of the first capacitor C1 is connected to a first terminal of the second capacitor C2.

The first terminal of the second capacitor C2 is further connected to the second output terminal of the output control circuit 300, and the second terminal of the second capacitor C2 is connected to ground.

It will be appreciated that ac power will produce voltage variations at the line input and the neutral input of the power input 100 during a cycle. In each ac power supply cycle, when the voltage value corresponding to the detected voltage signal is smaller than the set voltage value, and the voltage of the live wire input end of the power input end 100 is greater than the voltage of the zero line input end of the power input end 100, the output control circuit 300, under the control of the control module 600, switches on the path from the zero line input end of the power input end 100 to the voltage doubling circuit 400, to form a first path: the live input end of the power input end 100 → the output control circuit 300 → the first capacitor C1 → the output control circuit 300 → the zero line input end of the power input end 100, so that the rectified power voltage charges the first capacitor C1 to a set voltage value; when the voltage value corresponding to the detection voltage signal is smaller than the set voltage value, and the voltage of the live wire input end of the power input end 100 is smaller than the voltage of the zero line input end of the power input end 100, the output control circuit 300 switches on the path from the zero line input end of the power input end 100 to the voltage doubling circuit 400 under the control of the control module 600, so as to form a second path: the neutral input terminal of the power input terminal 100 → the output control circuit 300 → the second capacitor C2 → the output control circuit 300 → the live input terminal of the power input terminal 100, so that the rectified power voltage charges the second capacitor C2 to the set voltage value.

In practical applications, the voltage values of the first capacitor C1 and the second capacitor C2 can reach the peak value of the input ac power voltage. In this way, the voltage doubling circuit 400 can double the input power voltage to twice the peak value of the input ac power voltage in each ac power cycle.

The voltage doubling is realized by the first capacitor C1 and the second capacitor C2, and the voltage balance is realized by setting the set voltage value to make the voltage values of the first capacitor C1 and the second capacitor C2 always follow the set voltage value. The problem that the circuit loss is increased due to the fact that resistors are connected in parallel at two ends of a capacitor to achieve voltage balance in the traditional voltage doubling circuit 400 is solved.

Referring to fig. 3, in an embodiment, the output control circuit 300 includes a rectifying circuit 310 and a switching circuit 320.

The rectifying circuit 310 has a first end, a second end, a third end and a fourth end, the first end of the rectifying circuit 310 is connected with the live wire input end of the power input end 100, the second end of the rectifying circuit 310 is connected with the zero wire input end of the power input end 100, the third end of the rectifying circuit 310 is connected with the first end of the first capacitor C1, the fourth end of the rectifying circuit 310 is connected with the second end of the second capacitor C2, and the rectifying circuit 310 is used for rectifying and outputting the input alternating current power supply voltage.

The controlled end of the switch circuit 320 is connected to the control module 600, the input end of the switch circuit 320 is connected to the neutral input end of the power input end 100, and the output end of the switch circuit 320 is connected to both the second end of the first capacitor C1 and the first end of the second capacitor C2.

The switch circuit 320 is configured to switch on a path between the power input terminal 100 and the voltage doubling circuit 400 under the control of the control module 600 when a voltage value corresponding to the detection voltage signal is smaller than a set voltage value, and switch off a path between a zero line input terminal of the power input terminal 100 and the voltage doubling circuit 400 under the control of the control module 600 when the voltage value corresponding to the detection voltage signal is greater than or equal to the set voltage value.

The rectifier circuit 310 rectifies the ac power supply voltage input from the power supply input terminal 100, converts the ac power supply voltage into a dc power supply voltage, and outputs the dc power supply voltage. When the voltage value corresponding to the detection voltage signal is smaller than the set voltage value, the control module 600 controls the switch circuit 320 to switch on the path between the power input terminal 100 and the voltage doubling circuit 400, so that the voltage doubling circuit 400 doubles the rectified power voltage and outputs the doubled power voltage to the power output terminal 200; when the voltage value corresponding to the detection voltage signal is greater than or equal to the set voltage value, the control module 600 controls the switch circuit 320 to disconnect the path between the power input terminal 100 and the voltage doubling circuit 400, so that the rectified power voltage is directly output to the power output terminal 200.

In the present embodiment, when the voltage value corresponding to the detection voltage signal is smaller than the set voltage value, the switch circuit 320 switches on the path between the power input terminal 100 and the voltage doubling circuit 400; when the voltage value corresponding to the detection voltage signal is greater than or equal to the set voltage value, the path between the power input end 100 and the voltage doubling circuit 400 is disconnected, the situation that the output voltage of the voltage doubling adjusting circuit is too high and a subsequent circuit is damaged is prevented, and automatic voltage doubling adjustment of the input power voltage is realized.

Referring to fig. 3, in an embodiment, the rectifying circuit 310 includes a first diode D1, a second diode D2, a third diode D3, and a fourth diode D4.

The cathode of the first diode D1 is connected to the hot input of the power input 100, and the anode of the first diode D1 is connected to the first terminal of the first capacitor C1.

The cathode of the second diode D2 is connected to the neutral input of the power input 100 and the anode of the second diode D2 is connected to the first terminal of the first capacitor C1.

The cathode of the third diode D3 is connected to the second terminal of the second capacitor C2, and the anode of the third diode D3 is connected to the hot input terminal of the power input terminal 100.

The cathode of the fourth diode D4 is connected to the second terminal of the second capacitor C2, and the anode of the third diode D3 is connected to the neutral input of the power input 100.

In each alternating current power supply cycle, when the voltage value corresponding to the detection voltage signal is smaller than the set voltage value, and the voltage of the live wire input end of the power input end 100 is greater than the voltage of the zero line input end of the power input end 100, the first path specifically is as follows: the live input end of the power input end 100 → the first diode D1 → the first capacitor C1 → the switch circuit 320 → the neutral input end of the power input end 100; when the voltage value corresponding to the detection voltage signal is smaller than the set voltage value, and the voltage of the live wire input end of the power input end 100 is smaller than the voltage of the zero line input end of the power input end 100, the second path specifically includes: the neutral input of the power input 100 → the switching circuit 320 → the second capacitor C2 → the third diode D3 → the hot input of the power input 100.

Referring to fig. 3, in an embodiment, the switching circuit 320 includes a first switching circuit Q1 and a second switching circuit Q2.

And a first switch circuit Q1, wherein the controlled end of the first switch circuit Q1 is connected with the control module 600, and the input end of the first switch circuit Q1 is connected with the zero line input end of the power input end 100.

A controlled end of the second switch circuit Q2 and a controlled end of the second switch circuit Q2 are connected with the control module 600, an input end of the second switch circuit Q2 is connected with an output end of the first switch circuit Q1, and an output end of the second switch circuit Q2 is connected with both a second end of the first capacitor C1 and a first end of the second capacitor C2.

In the above embodiment, the first switch circuit Q1 may be a MOS transistor, and the second switch circuit Q2 may be a MOS transistor.

When the voltage value corresponding to the detection voltage signal is smaller than the set voltage value, the control module 600 controls the first switch circuit Q1 and the second switch circuit Q2 to be closed, and a path between the power input terminal 100 and the voltage doubling circuit 400 is switched on; when the voltage value corresponding to the detection voltage signal is greater than or equal to the set voltage value, the control module 600 controls the second switch circuit Q2 to open, so as to disconnect the path between the power input terminal 100 and the voltage doubling circuit 400.

In the embodiment, the first switch circuit Q1 is matched with the second switch circuit Q2, and when the voltage value corresponding to the detection voltage signal is smaller than the set voltage value, the path between the power input end 100 and the voltage doubling circuit 400 is switched on; when the voltage value corresponding to the detection voltage signal is greater than or equal to the set voltage value, the path between the power input terminal 100 and the voltage doubling circuit 400 is disconnected, and the voltage doubling adjustment of the input power voltage is automatically realized.

Referring to fig. 3, in one embodiment, the voltage detection circuit 500 includes a first resistor R1 and a second resistor R2.

The input end of the first resistor R1 is connected to the live input end of the power input end 100, and the output end of the first resistor R1 is connected to the control module 600.

The input end of the second resistor R2 is connected with the output end of the first switch circuit Q1, and the output end of the second resistor R2 is connected with the control module 600.

In the embodiment, the voltage detection circuit 500 is formed by the first resistor R1 and the second resistor R2 to detect the input ac power voltage, and the voltage detection circuit has a simple structure and is low in cost.

Referring to FIG. 4, in one embodiment, the voltage value V is set_SETLess than the peak value of the input ac supply voltage.

In the first half-wave (T0-T3) of each ac power cycle, the control module 600 is configured to detect that the voltage value corresponding to the voltage signal is less than the set voltage value V_SETAt this time, the first switch circuit Q1 and the second switch circuit Q2 are controlled to be turned on to connect the path between the zero line input end of the power input end 100 and the first capacitor C1, so that the voltage doubling circuit 400 doubles the rectified power voltage and outputs the doubled power voltage to the power output end 200.

In the first half-wave (T0-T3) of each AC power cycle, the control module 600 is used to detect whether the voltage value corresponding to the voltage signal is greater than or equal to the set voltage value V_SETWhen the power supply is started, the first switch circuit Q1 is controlled to be switched on, the second switch circuit Q2 is controlled to be switched off, so that a path between a zero line input end of the power supply input end 100 and the first capacitor C1 is cut off, and the rectified power supply voltage is output to the power supply output end 200; the control module 600 is further configured to perform voltage sampling and record that a voltage value corresponding to the detected voltage signal is greater than or equal to the set voltage value V_SETThe time period of (a).

In each period of the AC powerIn the second half-wave (T3-T6), the control module 600 is configured to detect that the voltage value corresponding to the voltage signal is smaller than the set voltage value V_SETAt this time, the first switch circuit Q1 and the second switch circuit Q2 are controlled to be turned on to connect the path between the zero line input end of the power input end 100 and the second capacitor C2, so that the voltage doubling circuit 400 doubles the rectified power voltage and outputs the doubled power voltage to the power output end 200.

In the second half-wave (T3-T6) of each ac power cycle, the control module 600 is further configured to control the first switch circuit Q1 and the second switch circuit Q2 to open during the time period corresponding to the first half-wave, so as to open the path between the zero line input end of the power input end 100 and the second capacitor C2, and output the rectified power voltage to the power output end 200.

Referring to fig. 3, T0-T6 are a complete ac power cycle, where T0-T3 are first half-waves at which the voltage at the live input end of the power input 100 is greater than the voltage at the neutral input end; T3-T6 are the second half-wave, and at this time, the voltage at the live input end of the power input end 100 is smaller than the voltage at the neutral input end. It will be appreciated that the waveforms of the first half-wave and the second half-wave are centrosymmetric due to the characteristics of the ac power source.

Within the time from T0 to T1, the voltage of the live wire input end of the power supply input end 100 is larger than the voltage of the zero wire input end, and the input alternating current power supply voltage value is smaller than the set voltage value V_SETThe control module 600 controls the first switch circuit Q1 and the second switch circuit Q2 to be turned on, a path between the zero line input end of the power input end 100 and the first capacitor C1 is switched on, and the rectified power voltage charges the first capacitor C1 to a set voltage value V1_SET。

Within the time from T1 to T2, the voltage of the live wire input end of the power supply input end 100 is greater than the voltage of the zero wire input end, and the input alternating current power supply voltage value is greater than the set voltage value V_SETThe control module 600 controls the first switch circuit Q1 to be turned on, and the second switch circuit Q2 to be turned off, so as to break the path between the zero line input end of the power input end 100 and the first capacitor C1 and stop charging the first capacitor C1. During this period, the control module 600 samples the incoming AC supply voltage and records itThe voltage value corresponding to the detection voltage signal is greater than or equal to the set voltage value V_SETThe time period of (a).

Within the time from T2 to T3, the voltage of the live wire input end of the power supply input end 100 is larger than the voltage of the zero wire input end, and the input alternating current power supply voltage value is smaller than the set voltage value V_SETThe control module 600 controls the first switch circuit Q1 and the second switch circuit Q2 to be turned on, so as to switch on a path between the zero line input end of the power input end 100 and the first capacitor C1, and the rectified power voltage charges the first capacitor C1.

Within the time from T3 to T4, the voltage of the live wire input end of the power supply input end 100 is smaller than the voltage of the zero wire input end, and the input alternating current power supply voltage value is smaller than the set voltage value V_SETThe control module 600 controls the first switch circuit Q1 and the second switch circuit Q2 to remain on, and switches on the path between the zero line input end of the power input end 100 and the second capacitor C2, and the rectified power voltage charges the second capacitor C2 to the set voltage value V_SET。

Within the time from T4 to T5, the voltage of the live wire input end of the power supply input end 100 is smaller than the voltage of the zero wire input end, and the voltage value of the input alternating current power supply is larger than the set voltage value V_SET. Since the first half-wave and the second half-wave are centrosymmetric, the time period from T4 to T5 is the same as the time period from T1 to T2, and the control module 600 controls the first switch circuit Q1 and the second switch circuit Q2 to be turned off in the time period corresponding to from T1 to T2, so as to stop charging the second capacitor C2.

Within the time from T5 to T6, the voltage of the live wire input end of the power supply input end 100 is smaller than the voltage of the zero wire input end, and the input alternating current power supply voltage value is smaller than the set voltage value V_SETThe control module 600 controls the first switch circuit Q1 and the second switch circuit Q2 to be turned on, and switches on a path between the zero line input end of the power input end 100 and the second capacitor C2, so that the rectified power voltage charges the second capacitor C2.

In this embodiment, the control module 600 controls the first switch circuit Q1 and the second switch circuit Q2, and further controls the voltage-doubling voltage of the first capacitor C1 and the second capacitor C2 to follow the set voltage, so as to realize the voltage balance of the voltage-doubling circuit 400 and prevent the voltage-doubling adjusting circuit from damaging the subsequent circuit due to too high output voltage. The problem that the traditional voltage doubling circuit cannot automatically perform voltage doubling adjustment on the input power supply voltage is solved.

Referring to fig. 3, in an embodiment, the voltage doubling adjusting circuit further includes a first power supply circuit 700.

The input end of the first power supply circuit 700 is configured to be connected to the power input end 100, the output end of the first power supply circuit 700 is connected to the control module 600, and the first power supply circuit 700 is configured to supply power to the control module 600 when an ac power supply is initially connected.

When the voltage doubling adjusting circuit is connected to an ac power supply, the first switch circuit Q1 and the second switch circuit Q2 are in an off state, the power input terminal 100 charges the first capacitor C1, and then the first capacitor C1 charges the first power supply circuit 700, and when the voltage of the first power supply circuit 700 reaches the start voltage of the control module 600, the control module 600 starts to operate. Of course, the first power supply circuit 700 may also supply power to the control module 600 when the control module 600 is in operation.

In this embodiment, the first power supply circuit 700 supplies power to the control module 600 at the initial time of accessing the power supply, and when the starting voltage of the control module 600 is reached, the control module 600 starts to work, so that the response speed is high.

Referring to fig. 3, in an embodiment, the first power supply circuit 700 includes a third resistor R3, a third capacitor C3, and a fifth diode D5.

The input end of the third resistor R3 is used for being connected with the power supply input end 100, and the output end of the third resistor R3 is connected with the input end of the control device.

The first end of the third capacitor C3 is connected to the output end of the third resistor R3, and the second end of the third capacitor C3 is grounded.

An anode of the fifth diode D5 is connected to the output terminal of the third resistor R3, and a cathode of the fifth diode D5 is grounded.

When the voltage doubling adjusting circuit is connected to an ac power supply, the first switch circuit Q1 and the second switch circuit Q2 are in an off state, the power input terminal 100 charges the first capacitor C1, the first capacitor C1 charges the third capacitor C3 through the third resistor R3, and when the voltage of the first capacitor C1 reaches the start voltage of the control module 600, the control module 600 starts to operate. The fifth diode D5 is a zener diode to prevent the circuit from working normally due to excessive voltage.

The present embodiment supplies power to the control module 600 through the third capacitor C3 at the initial time of accessing the power supply, and due to the characteristic that the capacitor can filter out noise, the stable power supply voltage can be supplied to the control module 600 at the initial time.

Referring to fig. 3, in an embodiment, the voltage doubling adjusting circuit further includes a second power supply circuit 800.

The input end of the second power supply circuit 800 is used for accessing a power supply voltage, the output end of the second power supply circuit 800 is connected with the control module 600, and the second power supply circuit 800 is used for supplying power to the control module 600 when the control module 600 works.

In this embodiment, the second power supply circuit 800 supplies power to the control module 600 by using the power supply voltage processed by the internal circuit (e.g., the charging circuit or the voltage reduction circuit), so that the circuit loss is small.

In one embodiment, the second power supply circuit 800 includes a fourth resistor R4 and a sixth diode D6.

Referring to fig. 3, a cathode of the sixth diode D6 is used for receiving a supply voltage, an anode of the sixth diode D6 is connected to an input terminal of the fourth resistor R4, and an output terminal of the fourth resistor R4 is connected to the control device.

In the embodiment, the fourth resistor R4 and the sixth diode D6 supply power to the control module 600 by using the power supply voltage processed by the internal circuit (for example, a charging circuit or a voltage reduction circuit), so that the circuit loss is small.

In one embodiment, the voltage value V is set_SETGreater than the peak value of the input ac supply voltage. Since the voltage-doubling adjusting circuit is connected to different ac power voltages, the peak value of the input ac power voltage is smaller than the preset voltage value, and theoretically, the control module 600 is required to control the first switch circuit Q1 and the second switch circuit Q2 to be always turned on, so as to adjust the voltage-doubling adjusting circuit according to the input ac power voltageThe voltage doubling circuit is enabled to carry out voltage doubling.

Referring to fig. 5, T00-T40 are a complete ac power cycle, where T00-T30 are first half-waves at which the voltage at the live input of the power input 100 is greater than the voltage at the neutral input; T30-T40 are the second half-wave, and at this time, the voltage at the live input end of the power input end 100 is smaller than the voltage at the neutral input end.

Within the time from T00 to T10, the voltage of the live wire input end of the power supply input end 100 is larger than the voltage of the zero wire input end, and the input alternating current power supply voltage value is smaller than the set voltage value V_SETThe control module 600 controls the first switch circuit Q1 and the second switch circuit Q2 to be turned on, and the path between the zero line input end of the power input end 100 and the first capacitor C1 is switched on, so that the rectified power voltage charges the first capacitor C1.

Within the time from T10 to T20, the voltage of the live wire input end of the power supply input end 100 is greater than the voltage of the zero wire input end, and the input alternating current power supply voltage value is less than the set voltage value V_SETThe control module 600 controls the first switch circuit Q1 and the second switch circuit Q2 to remain on, and switches on a path between the zero line input end of the power input end 100 and the first capacitor C1, so that the rectified power voltage charges the first capacitor C1 to the peak voltage of the input ac power voltage.

Within the time from T20 to T30, the voltage of the live wire input end of the power supply input end 100 is larger than the voltage of the zero wire input end, and the input alternating current power supply voltage value is smaller than the set voltage value V_SET. Ideally, the control module 600 should continue to control the first and second switching circuits Q1 and Q2 to remain on. However, if the first switch circuit Q1 and the second switch circuit Q2 remain conductive, the ground reference of the second power supply circuit 800 will be pulled to the first end of the second capacitor through the first switch circuit and the second switch circuit. At this time, since the voltage at the first end of the second capacitor C2 is greater than the voltage at the input end of the second power supply circuit 800, the sixth diode D6 is turned off, and the second power supply circuit 800 cannot supply power to the control module 600. Therefore, the control module 600 controls the first switch circuit Q1 to be turned on, the second switch circuit Q2 to be turned off, and the reference ground of the second power supply circuit 800 is pulled to the second terminal of the second capacitor C2, so thatThe voltage at the input of the second power supply circuit 800 is greater than the voltage of the second power supply circuit 800 with reference to ground to supply power to the control module 600.

In the time from T20 to T30, the voltage of the live wire input end of the power supply input end 100 is smaller than the voltage of the zero wire input end, and the input alternating current power supply voltage value is smaller than the set voltage value V_SETThe control module 600 controls the first switch circuit Q1 and the second switch circuit Q2 to be turned on, and switches on a path between the zero line input end of the power input end 100 and the second capacitor C2, so that the rectified power voltage charges the second capacitor C2.

The principles of the present invention will be described in detail below with reference to the accompanying drawings:

the first switching circuit Q1 and the second switching circuit Q2 are initially in an off state, the power input terminal 100 is connected to an ac power supply, and the rectifying circuit 310 rectifies an ac power supply voltage into a dc power supply voltage. The rectified power voltage charges the first capacitor C1, and then the first capacitor C1 charges the third capacitor R3 through the third resistor R3, and when the voltage of the third capacitor C3 reaches the start voltage of the control module 600, the control module 600 starts to operate. At this time, the voltages of the second terminal of the first capacitor C1 and the first terminal of the second capacitor C2 are half of the input ac power voltage.

Set voltage value V_SET(e.g., 50V) is less than the peak value of the input ac supply voltage (e.g., 120V):

within the time from T0 to T1, the voltage of the live wire input end of the power supply input end 100 is larger than the voltage of the zero wire input end, and the input alternating current power supply voltage value is smaller than the set voltage value V_SETThe control module 600 controls the first switch circuit Q1 and the second switch circuit Q2 to remain on, and opens a path between the neutral input of the power input 100 and the first capacitor C1 to form a first path: the live input of the power input 100 → the first diode → the first capacitor C1 → the switch circuit 320 → the neutral input of the power input 100. The rectified power supply voltage charges the first capacitor C1 to a set voltage value V through the first path_SET。

Within the time from T1 to T2, the voltage of the live wire input end of the power supply input end 100 is larger than the voltage of the zero wire input endAnd the voltage value of the input alternating current power supply is greater than the set voltage value V_SETThe control module 600 controls the first switch circuit Q1 to be turned on, and the second switch circuit Q2 to be turned off, so as to break the path between the zero line input end of the power input end 100 and the first capacitor C1 and stop charging the first capacitor C1.

During this period, the control module 600 samples the input ac power voltage and records that the voltage value corresponding to the detected voltage signal is greater than or equal to the set voltage value V_SETThe time period of (a).

Within the time from T2 to T3, the voltage of the live wire input end of the power supply input end 100 is larger than the voltage of the zero wire input end, and the input alternating current power supply voltage value is smaller than the set voltage value V_SETThe control module 600 controls the first switch circuit Q1 and the second switch circuit Q2 to be turned on, a path between the zero line input end of the power input end 100 and the first capacitor C1 is switched on, and the rectified power voltage charges the first capacitor C1 through the first path.

Within the time from T3 to T4, the voltage of the live wire input end of the power supply input end 100 is smaller than the voltage of the zero wire input end, and the input alternating current power supply voltage value is smaller than the set voltage value V_SETThe control module 600 controls the first switch circuit Q1 and the second switch circuit Q2 to remain on, and closes a path between the neutral input of the power input 100 and the second capacitor C2 to form a second path: the neutral input of the power input 100 → the switching circuit 320 → the second capacitor C2 → the third diode → the hot input of the power input 100. The rectified power supply voltage charges the second capacitor C2 to the set voltage value V through the second path_SET。

Within the time from T4 to T5, the voltage of the live wire input end of the power supply input end 100 is smaller than the voltage of the zero wire input end, and the voltage value of the input alternating current power supply is larger than the set voltage value V_SET. Since the first half-wave and the second half-wave are centrosymmetric, the time period from T4 to T5 is the same as the time period from T1 to T2, and the control module 600 controls the first switch circuit Q1 and the second switch circuit Q2 to be turned off in the time period corresponding to from T1 to T2, so as to stop charging the second capacitor C2.

Within the time from T5 to T6, the voltage of the live wire input end of the power supply input end 100 is smaller than the voltage of the zero wire input end, and the input alternating current power supply voltage value is smaller than the set voltage value V_SETThe control module 600 controls the first switch circuit Q1 and the second switch circuit Q2 to be turned on, a path between the zero line input end of the power input end 100 and the second capacitor C2 is switched on, and the rectified power voltage charges the second capacitor C2 through the second path.

The next cycle is entered starting at T6. In the time period from T0 to T6, the control module 600 may be powered by the first power supply circuit 700 or the second power supply circuit 800. The voltage values of the first capacitor C1 and the second capacitor C2 can reach the peak value of the input alternating current power supply voltage due to the fact that the first capacitor C1 and the second capacitor C2 can reach the peak value of the input alternating current power supply voltage. Therefore, the voltage doubling circuit 400 can double the input power supply voltage to twice the peak value of the input ac power supply voltage in each ac power supply cycle. Thus, the T0-T6 controls the first capacitor C1 and the second capacitor C2 in one period of the AC power voltage, so that the voltages of the first capacitor C1 and the second capacitor C2 always follow the set voltage value V_SETThe voltage balance is realized, and the voltage doubling circuit 400 is prevented from outputting excessive voltage by voltage doubling when the input power supply voltage is excessive, so that a rear-stage circuit is prevented from being damaged.

Set voltage value V_SET(e.g., 150V) is greater than the peak value of the input ac supply voltage (e.g., 120V):

within the time from T00 to T10, the voltage of the live wire input end of the power supply input end 100 is larger than the voltage of the zero wire input end, and the input alternating current power supply voltage value is smaller than the set voltage value V_SETThe control module 600 controls the first switch circuit Q1 and the second switch circuit Q2 to be turned on, and a path between the zero line input end of the power input end 100 and the first capacitor C1 is switched on to form a first path: the live input of the power input 100 → the first diode → the first capacitor C1 → the switch circuit 320 → the neutral input of the power input 100. The rectified supply voltage charges the first capacitor C1.

Within the time from T10 to T20, the voltage of the live wire input end of the power supply input end 100 is larger than the electricity of the zero wire input endVoltage, and the voltage value of the input AC power supply is less than the set voltage value V_SETThe control module 600 controls the first switch circuit Q1 and the second switch circuit Q2 to remain on, and opens a path between the neutral input of the power input 100 and the first capacitor C1 to form a first path: the live input of the power input 100 → the first diode → the first capacitor C1 → the switch circuit 320 → the neutral input of the power input 100. The rectified mains voltage charges the first capacitor C1 to the peak voltage of the input ac mains voltage.

Within the time from T20 to T30, the voltage of the live wire input end of the power supply input end 100 is larger than the voltage of the zero wire input end, and the input alternating current power supply voltage value is smaller than the set voltage value V_SET. Ideally, the control module 600 should continue to control the first and second switching circuits Q1 and Q2 to remain on. However, if the first switch circuit Q1 and the second switch circuit Q2 remain conductive, the ground reference of the second power supply circuit 800 will be pulled to the first end of the second capacitor through the first switch circuit and the second switch circuit. At this time, since the voltage at the first end of the second capacitor C2 is greater than the voltage at the input end of the second power supply circuit 800, the sixth diode D6 is turned off, and the second power supply circuit 800 cannot supply power to the control module 600. Therefore, the control module 600 controls the first switch circuit Q1 to be turned on, and the second switch circuit Q2 to be turned off, so as to pull the ground reference of the second power supply circuit 800 to the second terminal of the second capacitor C2, and make the voltage at the input terminal of the second power supply circuit 800 greater than the voltage of the ground reference of the second power supply circuit 800, so as to supply power to the control module 600.

In the time from T20 to T30, the voltage of the live wire input end of the power supply input end 100 is smaller than the voltage of the zero wire input end, and the input alternating current power supply voltage value is smaller than the set voltage value V_SETThe control module 600 controls the first switch circuit Q1 and the second switch circuit Q2 to be turned on, and a path between the zero line input end of the power input end 100 and the second capacitor C2 is switched on to form a second path: the neutral input of the power input 100 → the switching circuit 320 → the second capacitor C2 → the third diode → the hot input of the power input 100. The rectified supply voltage charges a second capacitor C2.

According to the invention, the set voltage value is set, the control module controls the switch circuit, and then the voltage doubling circuit is controlled, so that the input power supply voltage is automatically doubled. Meanwhile, due to the fact that the set voltage value is set, the voltages of the first capacitor and the second capacitor always follow the set voltage value, voltage balance is achieved, and resistors do not need to be connected in parallel to the two ends of the capacitors. The problem that the traditional voltage doubling circuit cannot automatically perform voltage doubling adjustment on the input power supply voltage is solved.

The above description is only an alternative embodiment of the present invention, and not intended to limit the scope of the present invention, and all modifications and equivalents of the present invention, which are made by the contents of the present specification and the accompanying drawings, or directly/indirectly applied to other related technical fields, are included in the scope of the present invention.