阅读说明：本技术 一种延时下电保护电路 (Time-delay power-off protection circuit ) 是由 张庆超 刘亚兵 李征鸿 于 2020-12-09 设计创作，主要内容包括：本申请提供了一种延时下电保护电路,包括：电容C1和电容C2构成的充电滤波电路,电源输入后经过并联的电容C1和电容C2后接地,用于滤掉输入电源带来的高频和低频信号干扰；二极管D1构成的防反接电路,电压输入电源输入后连接二极管D1的阳极,二极管D1的阴极接向电源输出,防止输入电源正负极反接带来的损害；限流电阻R0、充放电电容C3和二极管D2构成的充放电电路,限流电阻R0的正端接二极管D1的阴极,限流电阻R0的负端一路接向充放电电容C3、另一路接二极管D2阳极,二极管D2的阴级与二极管D1的阴极连接后接向电源输出,用于实现对充放电电容C3的充放电管理；电容C4和电容C5构成的放电滤波电路,并联的电容C4和电容C5一端接电源输出、一端接地。(The application provides a time delay protection circuit that gives off electricity, include: the charging filter circuit is composed of a capacitor C1 and a capacitor C2, after power is input, the charging filter circuit is grounded through the capacitor C1 and the capacitor C2 which are connected in parallel, and is used for filtering high-frequency and low-frequency signal interference caused by the input power; the reverse connection prevention circuit formed by the diode D1 is characterized in that after a voltage input power supply is input, the voltage input power supply is connected with the anode of the diode D1, and the cathode of the diode D1 is connected with the power supply output, so that the damage caused by the reverse connection of the anode and the cathode of the input power supply is prevented; the charging and discharging circuit is composed of a current-limiting resistor R0, a charging and discharging capacitor C3 and a diode D2, the positive end of the current-limiting resistor R0 is connected with the cathode of a diode D1, one circuit of the negative end of the current-limiting resistor R0 is connected to the charging and discharging capacitor C3, the other circuit of the negative end of the current-limiting resistor R0 is connected to the anode of a diode D2, the cathode of a diode D2 is connected with the cathode of a diode D1 and then is connected to the power supply for outputting, and charging and discharging management of the; the capacitor C4 and the capacitor C5 are connected in parallel, one end of the capacitor C4 and one end of the capacitor C5 are connected with the power output, and the other end is connected with the ground.)

1. A time-delayed power-down protection circuit, the circuit comprising:

the charging filter circuit is composed of a first capacitor C1 and a second capacitor C2, after power is input, the charging filter circuit is grounded after passing through the first capacitor C1 and the second capacitor C2 which are connected in parallel, and is used for filtering high-frequency signals and low-frequency signal interference brought by the input power;

the reverse connection preventing circuit is composed of a first diode D1, the voltage input power supply is connected with the anode of a diode D1, the cathode of the first diode D1 is connected to the power supply output, and the damage caused by the reverse connection of the anode and the cathode of the input power supply is prevented;

the charging and discharging circuit is composed of a current-limiting resistor R0, a charging and discharging capacitor C3 and a second diode D2, the positive end of the current-limiting resistor R0 is connected with the cathode of a first diode D1, one circuit of the negative end of the current-limiting resistor R0 is connected to the charging and discharging capacitor C3, the other circuit is connected with the anode of a second diode D2, the cathode of the second diode D2 is connected with the cathode of the first diode D1 and then connected to the power supply output, and the charging and discharging circuit is used for realizing charging and discharging management of the charging and discharging capacitor C3; and

and a discharge filter circuit consisting of a fourth capacitor C4 and a fifth capacitor C5, wherein one end of the fourth capacitor C4 and one end of the fifth capacitor C5 which are connected in parallel are connected with the power output and the other end is grounded.

2. The time-delay power-down protection circuit of claim 1, wherein the capacitance of the first capacitor C1 is smaller than the capacitance of the second capacitor C2.

3. The time-delay power-down protection circuit as claimed in claim 1, wherein the capacitance of the fourth capacitor C4 is smaller than that of the fifth capacitor C5.

4. The delayed power-off protection circuit as claimed in claim 2 or 3, wherein the capacitance of said charging and discharging capacitor C3 is larger than the capacitance of any one of the first capacitor C1, the second capacitor C2, the fourth capacitor C4 and the fifth capacitor C5.

5. A motor controller comprising the delayed power down protection circuit of any of claims 1 to 4.

Technical Field

The application belongs to the technical field of airplane power supply management, and particularly relates to a delayed power-off protection circuit.

Background

There are two common power output circuits: firstly, a power supply directly supplies power to a load after filtering, when the power supply is powered off, a load end is powered off immediately, and meanwhile, the requirement of the circuit on the power supply output is high, and when the voltage fluctuation is large, the load end cannot work normally; secondly, the power supply is connected with a large capacitor in parallel after being filtered to supply power to the load, when the power supply is powered off, the large capacitor can maintain discharge for a period of time, but the power supply has the defects of overlarge charging current and unstable discharge, and has certain impact influence on a power grid.

Disclosure of Invention

It is an object of the present application to provide a delayed power down protection circuit to solve or mitigate at least one of the problems of the background art.

The technical scheme of the application is as follows: a time-delayed power down protection circuit, the circuit comprising:

the charging filter circuit is composed of a first capacitor C1 and a second capacitor C2, after power is input, the charging filter circuit is grounded after passing through the first capacitor C1 and the second capacitor C2 which are connected in parallel, and is used for filtering high-frequency signals and low-frequency signal interference brought by the input power;

the reverse connection preventing circuit is composed of a first diode D1, the voltage input power supply is connected with the anode of a diode D1, the cathode of the first diode D1 is connected to the power supply output, and the damage caused by the reverse connection of the anode and the cathode of the input power supply is prevented;

the charging and discharging circuit is composed of a current-limiting resistor R0, a charging and discharging capacitor C3 and a second diode D2, the positive end of the current-limiting resistor R0 is connected with the cathode of a first diode D1, one circuit of the negative end of the current-limiting resistor R0 is connected to the charging and discharging capacitor C3, the other circuit is connected with the anode of a second diode D2, the cathode of the second diode D2 is connected with the cathode of the first diode D1 and then connected to the power supply output, and the charging and discharging circuit is used for realizing charging and discharging management of the charging and discharging capacitor C3; and

and a discharge filter circuit consisting of a fourth capacitor C4 and a fifth capacitor C5, wherein one end of the fourth capacitor C4 and one end of the fifth capacitor C5 which are connected in parallel are connected with the power output and the other end is grounded.

Further, the capacitance of the first capacitor C1 is smaller than that of the second capacitor C2.

Further, the capacitance of the fourth capacitor C4 is smaller than that of the fifth capacitor C5.

Furthermore, the capacitance of the charging and discharging capacitor C3 is larger than that of any one of the first capacitor C1, the second capacitor C2, the fourth capacitor C4 and the fifth capacitor C5.

On the other hand, the technical scheme provided by the application is as follows: a motor controller comprises the time-delay power-off protection circuit.

The time-delay power-off protection circuit provided by the application adopts the charging filter circuit, the reverse-connection-preventing circuit, the charging and discharging circuit and the discharging filter circuit, and compared with the simple direct connection of the VIN power supply and the output of the VIN power supply through a large capacitor, the time-delay power-off protection circuit has no voltage jump and no current impact, has the advantages of low failure rate, high reliability, small interference of power grid fluctuation on load power utilization and the like, and can ensure that the load stably works within a certain time after the power grid is powered off.

Drawings

In order to more clearly illustrate the technical solutions provided by the present application, the following briefly introduces the accompanying drawings. It is to be expressly understood that the drawings described below are only illustrative of some embodiments of the invention.

Fig. 1 is a circuit diagram of the present application.

Fig. 2 is a schematic diagram of a motor controller having the delayed power down protection circuit of the present application.

Detailed Description

In order to make the implementation objects, technical solutions and advantages of the present application clearer, the technical solutions in the embodiments of the present application will be described in more detail below with reference to the drawings in the embodiments of the present application.

In order to overcome the technical problems in the traditional power supply, the application provides a delay power-off protection circuit so as to achieve the purposes of small starting impact current, prevention of reverse connection of the power supply and delay power-off.

As shown in fig. 1, the delay power-off protection circuit mainly includes a charging filter circuit, an anti-reverse connection circuit, a charging and discharging circuit and a discharging filter circuit, wherein the charging filter circuit is composed of a capacitor C1 and a capacitor C2, and a VIN power supply is grounded after being input through a capacitor C1 and a capacitor C2 which are connected in parallel, and is mainly used for filtering out interference of high-frequency signals and low-frequency signals brought by the VIN input power supply; the anti-reverse connection circuit is composed of a diode D1, the VIN power supply is connected with the anode of a diode D1 after being input, and the cathode of a diode D1 is connected with a backward-stage circuit and used for preventing damage caused by reverse connection of the anode and the cathode of the input power supply; the charging and discharging circuit consists of a current-limiting resistor R0, a charging and discharging capacitor C3 and a diode D2, the positive end of the current-limiting resistor R0 is connected with the cathode of the diode D1, one circuit of the negative end of the current-limiting resistor R0 is connected to the capacitor C3 and then grounded, the other circuit is connected with the anode of the diode D2, the cathode of the diode D2 is connected with the cathode of the diode D1 and then connected to a post-stage circuit, and charging and discharging management of the charging and discharging capacitor C3 is completed; the discharge filter circuit is composed of a capacitor C4 and a capacitor C5, one end of the capacitor C4 and one end of the capacitor C5 which are connected in parallel are connected to the backward stage circuit, and the other end of the capacitor C4 and one end of the capacitor C5 are grounded, so that the function of the discharge filter circuit is the same as that of the charge filter circuit.

In the preferred embodiment of the above solution, the capacitance of the capacitor C1 is smaller than the capacitance of the second capacitor C2; similarly, the capacitance of the fourth capacitor C4 is smaller than the capacitance of the fifth capacitor C5.

Further, the capacitance of the charge and discharge capacitor C3 is larger than that of any one of the first capacitor C1, the second capacitor C2, the fourth capacitor C4 and the fifth capacitor C5.

At the time delay power-off circuit of this application, grid power VIN filters high frequency and low frequency interference signal through the filter circuit that charges earlier, then all the way through diode D1, resistance R0 after to electric capacity C3 charge, because resistance R0, starting current can restrict, can not because of the too big damage diode D1 of starting instantaneous impulse current, through a period, electric capacity C3 charges and accomplishes, another way is direct to the load power supply. When the VIN power supply network power source VIN is powered off, the capacitor C3 discharges, the discharge current does not pass through the resistor R0 any more, but passes through the diode D2 and then flows to the rear end, the high-frequency and low-frequency interference signals are filtered out through the discharge filter circuit again, then power is supplied to the load, and after a period of time, the capacitor C3 finishes discharging. Meanwhile, the charge and discharge circuit can compensate the problem of unstable voltage caused by power grid fluctuation. Finally, the purposes of reverse connection prevention, power-on current limiting and delayed power-off protection are achieved, and the effect of stabilizing output voltage is achieved.

As shown in fig. 2, in the control of the high-voltage brushless dc motor, the VIN power supply is a 28V low-voltage dc power supply to supply power to the control circuit, and the 270V power supply supplies power to the power circuit, that is, the motor. In the whole control process, the control circuit controls the on and off of the upper and lower switching tubes of the three-phase inverter bridge according to a certain sequence, so as to control the motor to rotate stably. When the power supply is off the network, 28V (VIN) and 270V are powered down. The power circuit needs a discharge circuit to discharge due to the existence of the pre-charging module (energy storage capacitor). By using the invention, the 28V power supply of the control circuit is kept effective, and the on and off of the upper and lower switching tubes of the three-phase inverter bridge can be continuously controlled according to a certain sequence until the 28V power supply of the control circuit fails after a period of time. By selecting the capacitance value of the capacitor C3, the discharge time of the charge and discharge circuit is long enough, the power circuit is ensured to be discharged first, and the control circuit is controlled to be discharged later.

The time-delay power-off protection circuit adopts the charging filter circuit, the reverse-connection-preventing circuit, the charging and discharging circuit and the discharging filter circuit, compared with the simple direct connection of the VIN power supply and the output of the VIN power supply through a large capacitor, after power is turned off, power electricity drops firstly, and the power failure sequence after power is controlled to enable the on and off of the upper and lower switch tubes of the three-phase inverter bridge to be always in a controllable state, the direct connection fault of the switch tubes on the upper and lower bridge walls can not occur, no voltage jump exists, no current impact exists, the fault rate is low, the reliability is high, and the power utilization interference of power grid fluctuation to a load is small. After the power grid is powered off, the load can be ensured to work stably within a certain time.

The above description is only for the specific embodiments of the present application, but the scope of the present application is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present application should be covered within the scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.