阅读说明：本技术 一种输入电压拓宽电路 (Input voltage widening circuit ) 是由 漆绍华 田中华 于 2019-11-29 设计创作，主要内容包括：一种输入电压拓宽电路,其包括分压单元、光电耦合开关单元、比较器控制单元和输出电压切换开关单元,外部电源与分压单元的输入端相连接,所述分压单元、光电耦合开关单元、比较器控制单元和输出电压切换开关单元依次连接,所述输出电压切换开关单元用于控制外部高电压输入端和外部低电压输入端之间的切换。该电路结构简单,宽电压输入高效控制,可将输入电压范围扩充,输入电压变宽可增加产品的共用性,还可以降低成本。(The utility model provides an input voltage widens circuit, its includes partial pressure unit, optoelectronic coupling switch unit, comparator control unit and output voltage change over switch unit, and external power source is connected with the input of partial pressure unit, optoelectronic coupling switch unit, comparator control unit and output voltage change over switch unit connect gradually, output voltage change over switch unit is used for controlling the switching between outside high voltage input end and the outside low-voltage input end. The circuit has simple structure, high-efficiency control of wide voltage input, expanded input voltage range, increased product sharing and lowered cost.)

1. The utility model provides an input voltage widens circuit which characterized in that it includes partial pressure unit, optoelectronic coupling switch unit, comparator control unit and output voltage change over switch unit, and external power source is connected with the input of partial pressure unit, optoelectronic coupling switch unit, comparator control unit and output voltage change over switch unit connect gradually, output voltage change over switch unit is used for controlling the switching between outside high voltage input end and the outside low-voltage input end.

2. The input voltage widening circuit as claimed in claim 1, wherein the voltage dividing unit includes a plurality of voltage dividing resistors and a protection resistor, the plurality of voltage dividing resistors are connected in series in sequence, an input terminal of the voltage dividing resistor is connected to an external power source, an output terminal of the voltage dividing resistor is connected to the photocoupling switch unit, an input terminal of the protection resistor is connected to an output terminal of the voltage dividing resistor, and an output terminal of the protection resistor is grounded.

3. The input voltage widening circuit as recited in claim 2, wherein the voltage dividing unit further comprises a filter capacitor, an input terminal of the filter capacitor is connected to a common terminal of the voltage dividing resistor and the protection resistor, and an output terminal of the filter capacitor is connected to a common terminal of the protection resistor and the ground terminal.

4. The input voltage broadening circuit as claimed in claim 2, wherein said photo-coupled switching unit includes a controllable voltage regulator and a photo-coupler, an input terminal of said photo-coupler is connected to a cathode of said controllable voltage regulator, a reference terminal of said controllable voltage regulator is connected to an output terminal of said voltage dividing resistor, an anode of said controllable voltage regulator is connected to a common terminal of said protection resistor and a ground terminal, and an output terminal of said photo-coupler is connected to said comparator control unit.

5. The input voltage widening circuit as recited in claim 4, wherein the comparator control unit comprises a first transistor, a MOS transistor, a second transistor, a first resistor, a second resistor, a third resistor, a fourth resistor, a fifth resistor, a sixth resistor, a seventh resistor, and an eighth resistor; one end of the first resistor is connected with an external 12V voltage end, the other end of the first resistor is connected with one output end of a photoelectric coupler, the other output end of the photoelectric coupler is connected with an emitting electrode of a first triode, a base electrode of the first triode is connected with a common end of the first resistor and the photoelectric coupler, a collector of the first triode is connected with one end of a second resistor, the other end of the second resistor is connected with one end of a third resistor, the other end of the third resistor is connected with a common end of the first resistor and the external 12V voltage end, a grid electrode of an MOS (metal oxide semiconductor) tube is connected with a common end of the second resistor and the third resistor, one end of a fourth resistor is connected with a common end of the third resistor and the MOS tube, the other end of the fourth resistor is connected with an emitting electrode of the first triode, and a source electrode of the MOS tube is connected with a common end of the fourth resistor and the first triode, the MOS transistor comprises a MOS tube, a fifth resistor, a fourth resistor, a fifth triode, a fifth resistor, a sixth resistor, an output voltage switching unit and a seventh resistor, wherein the drain electrode of the MOS tube is connected with one end of the fifth resistor, the other end of the fifth resistor is connected with an external 12V voltage end, the base electrode of the second triode is connected with the common end of the fifth resistor and the MOS tube, the emitter electrode of the second triode is connected with the common end of the MOS tube and the fourth resistor, the collector electrode of the second triode is connected with one end of the sixth resistor, the other end of the sixth resistor is connected with the external 12V voltage end, one end of the seventh resistor is connected with the common end of the sixth resistor and the second triode, the other end of the seventh resistor is connected with the eighth resistor, the other end of the eighth resistor is connected with the output voltage switching unit, and the emitter.

6. The input voltage widening circuit according to claim 5, wherein the comparator control unit further includes a first capacitor, a second capacitor, a third capacitor and a zener diode, one end of the first capacitor is connected to a common terminal of the photocoupler and the first resistor, the other end of the first capacitor is connected to a common terminal of the photocoupler and the emitter of the first triode, one end of the second capacitor is connected to a common terminal of the second resistor and the fourth resistor, the other end of the second capacitor is connected to a common terminal of the fourth resistor and the first triode, one end of the third capacitor is connected to the emitter of the second triode, the other end of the third capacitor is connected to a common terminal of the seventh resistor and the eighth resistor, one end of the zener diode is connected to a common terminal of the third capacitor and the second triode, and the other end of the voltage stabilizing diode is connected with the common end of the third capacitor and the eighth resistor.

7. The input voltage widening circuit as recited in claim 1, wherein the output voltage switching unit includes a relay switch, one end of an electromagnet of the relay switch is grounded, the other end of the electromagnet is connected to the comparator control unit, an armature output terminal of the relay switch is provided with a lead-out terminal, a high voltage terminal of the relay is connected to an external high voltage input terminal, and a low voltage terminal of the relay is connected to an external low voltage input terminal.

Technical Field

The invention relates to the field of circuits, in particular to an input voltage widening circuit.

Background

With the continuous improvement of living standard of people, energy storage power supplies are widely used, the requirement on the quality of electric energy is higher, the quality of original electric energy including a mains supply power grid can not meet the requirement of equipment, and the original electric energy can be used only after being converted by a power electronic device, and an inverter power supply is an indispensable important component part.

A good inverter power supply can not only improve output efficiency, but also prolong battery service life (standby loss is small and efficiency is high), but the traditional inverter has higher cost due to the fact that the withstand voltage value (usually 400V or 450V) of an output capacitor exceeds the specification, and is not beneficial to batch production, so that the range of input voltage of a product is limited.

The range of input voltages for the product can be deduced from the following equation: from the above formula, when Vout is 220V, it is necessary to consider that when the input voltage is the highest, 1.414 Vout is less than 435V (since the output capacitor uses a withstand voltage of 450V at the maximum, a 15V de-rating is reserved), the range of the input voltage is only 12V-16.8V, and it is also necessary to use a duty ratio adjustment process, which affects the efficiency of the product.

Disclosure of Invention

Aiming at the defects in the prior art, the invention provides the input voltage widening circuit which is simple in structure, high-efficiency in control of wide voltage input, capable of expanding the input voltage range, widening the input voltage, capable of improving the universality of products and capable of reducing the cost.

To achieve the above object, the present invention is realized by:

the utility model provides an input voltage widens circuit which characterized in that it includes partial pressure unit, optoelectronic coupling switch unit, comparator control unit and output voltage change over switch unit, and external power source is connected with the input of partial pressure unit, optoelectronic coupling switch unit, comparator control unit and output voltage change over switch unit connect gradually, output voltage change over switch unit is used for controlling the switching between outside high voltage input end and the outside low-voltage input end.

Further, the voltage division unit comprises a plurality of voltage division resistors and a protection resistor, the plurality of voltage division resistors are sequentially connected in series, the input end of each voltage division resistor is connected with an external power supply, the output end of each voltage division resistor is connected with the photoelectric coupling switch unit, the input end of each protection resistor is connected with the output end of each voltage division resistor, and the output end of each protection resistor is grounded.

Furthermore, the voltage division unit also comprises a filter capacitor, the input end of the filter capacitor is connected with the common end of the voltage division resistor and the protection resistor, and the output end of the filter capacitor is connected with the common end of the protection resistor and the grounding end.

Further, the photoelectric coupling switch unit comprises a controllable voltage stabilizer and a photoelectric coupler, the input end of the photoelectric coupler is connected with the cathode of the controllable voltage stabilizer, the reference electrode of the controllable voltage stabilizer is connected with the output end of the voltage dividing unit, the anode of the controllable voltage stabilizer is connected with the common end of the protective resistor and the grounding end, and the output end of the photoelectric coupler is connected with the comparator control unit.

Further, the comparator control unit comprises a first triode, an MOS (metal oxide semiconductor) tube, a second triode, a first resistor, a second resistor, a third resistor, a fourth resistor, a fifth resistor, a sixth resistor, a seventh resistor and an eighth resistor; one end of the first resistor is connected with an external 12V voltage end, the other end of the first resistor is connected with one output end of a photoelectric coupler, the other output end of the photoelectric coupler is connected with an emitting electrode of a first triode, a base electrode of the first triode is connected with a common end of the first resistor and the photoelectric coupler, a collector of the first triode is connected with one end of a second resistor, the other end of the second resistor is connected with one end of a third resistor, the other end of the third resistor is connected with a common end of the first resistor and the external 12V voltage end, a grid electrode of an MOS (metal oxide semiconductor) tube is connected with a common end of the second resistor and the third resistor, one end of a fourth resistor is connected with a common end of the third resistor and the MOS tube, the other end of the fourth resistor is connected with an emitting electrode of the first triode, and a source electrode of the MOS tube is connected with a common end of the fourth resistor and the first triode, the MOS transistor comprises a MOS tube, a fifth resistor, a fourth resistor, a fifth triode, a fifth resistor, a sixth resistor, an output voltage switching unit and a seventh resistor, wherein the drain electrode of the MOS tube is connected with one end of the fifth resistor, the other end of the fifth resistor is connected with an external 12V voltage end, the base electrode of the second triode is connected with the common end of the fifth resistor and the MOS tube, the emitter electrode of the second triode is connected with the common end of the MOS tube and the fourth resistor, the collector electrode of the second triode is connected with one end of the sixth resistor, the other end of the sixth resistor is connected with the external 12V voltage end, one end of the seventh resistor is connected with the common end of the sixth resistor and the second triode, the other end of the seventh resistor is connected with the eighth resistor, the other end of the eighth resistor is connected with the output voltage switching unit, and the emitter.

Further, the comparator control unit also comprises a first capacitor, a second capacitor, a third capacitor and a voltage stabilizing diode, one end of the first capacitor is connected with the common end of the photoelectric coupler and the first resistor, the other end of the first capacitor is connected with the common end of the photoelectric coupler and the emitter of the first triode, one end of the second capacitor is connected with the common end of the second resistor and the fourth resistor, the other end of the second capacitor is connected with the common end of the fourth resistor and the first triode, one end of the third capacitor is connected with the emitter of the second triode, the other end of the third capacitor is connected with the common end of the seventh resistor and the eighth resistor, one end of the voltage stabilizing diode is connected with the common end of the third capacitor and the second triode, and the other end of the voltage stabilizing diode is connected with the common end of the third capacitor and the eighth resistor. The first capacitor, the second capacitor and the third capacitor are arranged in the comparator control unit and play a role in filtering and protecting a circuit, and the voltage stabilizing diode is arranged to ensure that the output voltage to the output voltage switching unit is kept stable.

Further, the output voltage switching unit comprises a relay switch, one end of an electromagnet of the relay switch is grounded, the other end of the electromagnet is connected with the comparator control unit, an armature output end of the relay switch is provided with a leading-out end, a high voltage end of the relay is connected with an external high voltage input end, and a low voltage end of the relay is connected with an external low voltage input end.

The circuit has the advantages that the circuit is simple in structure, wide in voltage input and efficient in control, the input voltage range can be expanded, the universality of products can be improved due to the fact that the input voltage is widened, and cost can be reduced.

Drawings

Fig. 1 is a schematic diagram of an input voltage widening circuit.

Fig. 2 is a schematic diagram of a conventional circuit in an embodiment.

Fig. 3 is a schematic diagram of the first part of the circuit of fig. 2.

Fig. 4 is a second partial circuit schematic of fig. 2.

Fig. 5 is a third partial circuit schematic of fig. 2.

Fig. 6 is a schematic diagram of an input voltage widening circuit added to a prior art circuit diagram.

Fig. 7 is a schematic diagram of the first portion of the circuit of fig. 6.

Fig. 8 is a schematic diagram of the first portion of the circuit of fig. 7.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

Refer to fig. 1.

The utility model provides an input voltage widens circuit, its characterized in that it includes partial pressure unit, optoelectronic coupling switch unit, comparator control unit and output voltage change over switch unit, and external power source is connected with the input of partial pressure unit, and partial pressure unit, optoelectronic coupling switch unit, comparator control unit and output voltage change over switch unit connect gradually, and output voltage change over switch unit is used for controlling the switching between outside high voltage input end and the outside low-voltage input end.

In this embodiment, the voltage dividing unit includes a plurality of voltage dividing resistors and a protection resistor R54, specifically R51, R52, R53 and R48, the voltage dividing resistors R51, R52, R53 and R48 are sequentially connected in series, an input end of the voltage dividing resistor R51 is connected to an external power supply, an output end of the voltage dividing resistor R48 is connected to the photocoupling switch unit, an input end of the protection resistor R54 is connected to an output end of the voltage dividing resistor R48R, and an output end of the protection resistor R54 is grounded.

In this embodiment, the voltage dividing unit further includes a filter capacitor C35, an input terminal of the filter capacitor C35 is connected to a common terminal of the voltage dividing resistor and the photoelectric coupling switch unit, an output terminal of the filter capacitor C35 is connected to a common terminal of the protection resistor R54 and the ground terminal PGND, an input terminal of the protection resistor R54 is connected to a common terminal of the voltage dividing resistor R48 and the filter capacitor C35, and an output terminal of the protection resistor R54 is grounded PGND.

In this embodiment, the photo-coupler switch unit includes a controllable regulator IC4 and a photo-coupler PC4, where PC4A and PC4B are the same photo-coupler, PC4A is the input terminal of the photo-coupler and the output terminal of the PC4B photo-coupler, the input terminal PC4A of the photo-coupler is connected to the cathode of the controllable regulator IC4, the reference electrode of the controllable regulator IC4 is connected to the output terminal of the voltage dividing resistor R48, the anode of the controllable regulator IC4 is connected to the common terminal of the protection resistor R54 and the ground terminal PGND, and the output terminal PC4B of the photo-coupler is connected to the comparator control unit.

In this embodiment, the comparator control unit includes a first transistor Q8, a MOS transistor Q9, a second transistor Q10, a first resistor R101, a second resistor R59, a third resistor R102, a fourth resistor R40, a fifth resistor R103, a sixth resistor R104, a seventh resistor R120, and an eighth resistor R75; one end of a first resistor R101 is connected with an external 12V voltage end, the other end of the first resistor R101 is connected with one output end of a photocoupler PC4B, the other output end of the photocoupler PC4B is connected with an emitter of a first triode Q8, a base of the first triode Q8 is connected with a common end of the first resistor R101 and the photocoupler PC4B, a collector of a first triode Q8 is connected with one end of a second resistor R59, the other end of the second resistor R59 is connected with one end of a third resistor R102, the other end of the third resistor R102 is connected with a common end of the first resistor R101 and the external 12V voltage end, a gate of an MOS transistor Q9 is connected with a common end of the second resistor R59 and the third resistor R102, one end of the fourth resistor R40 is connected with a common end of the third resistor R102 and the MOS transistor Q9, and the other end of the fourth resistor R40 is connected with an emitter of the first triode Q8, the source of the MOS transistor Q9 is connected to a common end of the fourth resistor R40 and the first triode Q8, the drain of the MOS transistor Q9 is connected to one end of the fifth resistor R103, the other end of the fifth resistor R103 is connected to an external 12V voltage end, the base of the second triode Q10 is connected to a common end of the fifth resistor R103 and the MOS transistor Q9, the emitter of the second triode Q10 is connected to a common end of the MOS transistor Q9 and the fourth resistor R40, the collector of the second triode Q10 is connected to one end of the sixth resistor R104, the other end of the sixth resistor R104 is connected to an external 12V voltage end, one end of the seventh resistor R120 is connected to a common end of the sixth resistor R104 and the second triode Q10, the other end of the seventh resistor R120 is connected to the eighth resistor R75, the other end of the eighth resistor R75 is connected to the output voltage switching unit, and the emitter of the second triode Q10 is connected to a common end of the seventh resistor R120 and the eighth resistor R75.

In this embodiment, the comparator control unit further comprises a first capacitor C51, a second capacitor C44, one end of a first capacitor C51 is connected with a common end of a photocoupler PC4B and a first resistor R101, the other end of the first capacitor C51 is connected with a common end of a photocoupler PC4B and the emitter of a first triode Q8, one end of a second capacitor C44 is connected with a common end of a second resistor R59 and a fourth resistor R40, the other end of the second capacitor C44 is connected with a common end of a fourth resistor R40 and a first triode Q8, one end of a third capacitor C45 is connected with the emitter of a second triode Q10, the other end of the third capacitor C45 is connected with a common end of a seventh resistor R120 and an eighth resistor R75, one end of a zener diode ZD16 is connected with a common end of a third capacitor C45 and a second triode Q10, and the other end of a zener diode ZD16 is connected with a common end of a third capacitor C45 and an eighth resistor R75.

In this embodiment, the output voltage switching unit includes relay switch RY1, and 1 pin of one end of the electro-magnet of relay switch RY1 is ground connection, and 2 pins of the other end of the electro-magnet are connected with the comparator control unit, and 3 pins of armature output end of relay switch are provided with the leading-out terminal, and 4 pins of high voltage end of relay are connected with external high voltage input end, and 5 pins of low voltage end of relay are connected with external low voltage input end.

Referring to fig. 2-5, circuit diagrams commonly used in the prior art are shown.

Referring to fig. 6-8, for one application of the input voltage widening circuit in the embodiment, the input voltage range can be expanded from 12-16.8V to 12-30V.

The input end of the divider resistor R51 is connected with a control power supply, and is connected with a transformer after passing through the input voltage widening circuit, wherein the turn ratio of a coil of a pin 8 and a pin 10 of the transformer is designed according to the input low voltage of 12-15V, and the turn ratio of a coil of a pin 9 and a pin 10 of the transformer is designed according to the input high voltage of 15-30V; BAT + and BAT-are connected with the control power supply access port, and OUTA and OUTB are connected with the input power supply access port.

When the input voltage is in a low-voltage section of 12-15V (gear adjustment can be carried out according to actual requirements), the voltage at two ends of R54 in the circuit is lower than 2.5V, so that the PC4A is not conducted, because the PC4B (the PC4B and the PCB4A are the same photoelectric coupler) is not conducted, the Q9 is cut off when the Q8 is conducted, because the Q9 is cut off, the Q10 is conducted, because the Q10 is conducted, the power supply voltage of the relay switch RY1 is pulled down, so that the relay switch RY1 is not operated, the pin 8 of the transformer is communicated with the pin 3 of the relay, and the output is in a safe design range; when the input voltage exceeds 15V, when the R54 voltage reaches 2.5V after the voltage division is carried out by R51, R2, R53, R48 and R54, the PC4A is switched on, so that the PC4B is switched on, the Q8 is switched off, the Q9 is switched on, the Q9 is switched on, the Q10 is switched off, so that 12V supplies power to the relay, and the pin 3 of the armature output end of the relay switch RY1 is switched on with the pin 9 of the transformer, so that the output voltage is in a controllable range.

The circuit has the advantages that the circuit is simple in structure, wide in voltage input and efficient in control, the input voltage range can be expanded, the universality of products can be improved due to the fact that the input voltage is widened, and cost can be reduced.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents and improvements made within the spirit and principle of the present invention are intended to be included within the scope of the present invention.