A method for protecting a large capacity capacitor in a device from discharging and the device

Abstract

The present application relates to a kind of equipment in large capacity capacitor discharge protection method, discharge protection circuit and corresponding equipment, after the power outage of external power supply, the real-time voltage of energy storage capacitor is judged simultaneously when power outage, only when the power-off duration T exceeds the endurance time T1 of energy storage capacitor, the real-time supply voltage V of energy storage capacitor is lower than the effective working voltage V1 of external load, discharge switch is controlled to be turned on, and automatic discharge in equipment is carried out.After the power outage of external power supply, the present application ensures to carry out effective power supply to external load, meets the normal endurance power supply of external equipment, and can also carry out automatic discharge in equipment at reasonable time, can release the remaining electric quantity after no external equipment or external equipment has not worked.Based on real-time voltage judgment simultaneously, it is guaranteed that discharge switch is normally closed, and then sufficient discharge can be carried out to energy storage capacitor.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of electrical equipment, more particularly, to a method for discharging protection of large-capacity capacitor in equipment, a circuit for discharging protection of large-capacity capacitor in equipment, and an equipment with discharging protection of large-capacity capacitor in equipment. BACKGROUND

[0002] The large-capacity capacitor in electrical equipment is used for short-time large-current discharge scenarios, and can provide certain endurance capability for external loads and internal circuits. Through the role of large-capacity capacitor for internal endurance, when the equipment is disconnected from external power supply, discharge is performed relying on the consumption of internal circuits, so as to release the power stored on the capacitor.

[0003] However, in the use process of the large-capacity capacitor in some electrical equipment, the power consumption in the equipment is very small, and the large-capacity capacitor is mainly used for power supply of external equipment. Further, when the equipment is disconnected from external power supply, if the large-capacity capacitor is not discharged in time, the interface will be electrified for a long time, which poses a safety hazard to the storage and transportation process of the equipment. Some electrical equipment with high safety requirement level requires that after power-off, an external load is connected for full discharge before storage or transportation is allowed, but manual discharge cannot completely avoid safety hazards caused by human negligence.

[0004] The discharge circuit of the prior art basically only provides the most basic automatic discharge function, that is, automatic discharge through internal load after power-off, but has the disadvantages of insufficient discharge and inability to reasonably control the discharge timing. SUMMARY

[0005] The present application aims to overcome the shortcomings of the prior art, and provides a method for discharging protection of large-capacity capacitor in equipment, a discharge protection circuit, and an equipment with discharging protection of large-capacity capacitor in equipment, which can provide continuous endurance power supply for external loads after the equipment is powered off, and can timely release the residual power of the energy storage capacitor in the equipment, thereby avoiding safety hazards in the process of storing and transporting the electrified equipment.

[0006] The technical solution of the present application is as follows:

[0007] A method for discharging protection of large-capacity capacitor in equipment, comprising the following steps:

[0008] 1) detecting whether the external power supply is powered off, and if so, executing step 2);

[0009] 2) determining whether the power-off duration T exceeds the endurance duration T1 of the energy storage capacitor, and determining whether the real-time power supply voltage V of the energy storage capacitor is lower than the effective working voltage V1 of the external load;

[0010] 3) If T>T1 and V>V1, the discharge switch is controlled to be turned on, and the energy storage capacitor is discharged through the discharge load.

[0011] As a preferred, the real-time supply voltage V of the energy storage capacitor is detected in real time, and when the real-time supply voltage V is lower than the minimum working voltage V2 of the controller, the controller is powered off and turned off; the voltage pull-up module provides an enable pull-up voltage to the input end of the discharge switch, and the discharge switch keeps a normally closed state through the enable pull-up voltage.

[0012] A large-capacity capacitor discharge protection circuit in a device comprises a power-off detection module, a controller, a capacitor voltage detection module, a discharge switch, a discharge load, the energy storage capacitor and the discharge switch and the discharge load form a discharge loop, and the energy storage capacitor, the capacitor voltage detection module, the controller and the discharge switch form a discharge control loop.

[0013] After the power-off detection module detects that the external power supply is powered off, the controller performs timing and judges whether the power-off duration T exceeds the endurance duration T1 of the energy storage capacitor, and the capacitor voltage detection module judges whether the real-time supply voltage V of the energy storage capacitor is lower than the effective working voltage V1 of the external load; if T>T1 and V>V1, the controller controls the discharge switch to be turned on, and the energy storage capacitor is discharged through the discharge load.

[0014] As a preferred, the control input end of the discharge switch is connected with a voltage pull-up module, and an enable pull-up voltage is provided to the control input end of the discharge switch; when the real-time supply voltage V of the energy storage capacitor is lower than the minimum working voltage V2 of the controller, the discharge switch keeps a normally closed state through the enable pull-up voltage.

[0015] A device with large-capacity capacitor discharge protection in the device comprises a charging module, an energy storage capacitor and the discharge protection circuit of claim 3 or 4, and the charging module is connected with the energy storage capacitor and the capacitor voltage detection module of the discharge protection circuit.

[0016] As a preferred, the energy storage capacitor supplies power to the controller, the capacitor voltage detection module, the discharge switch and the voltage pull-up module of the discharge protection circuit.

[0017] The beneficial effects of the present application are as follows:

[0018] The device internal large-capacity capacitor discharge protection method, the discharge protection circuit and the corresponding device provided by the application can ensure effective power supply to the external load after the external power supply is powered off, meet normal endurance power supply of the external device, perform automatic discharge in the device at a reasonable time, release the remaining power after the external device is not working or has stopped working, ensure the normally closed discharge switch based on the real-time voltage judgment, and fully discharge the energy storage capacitor. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 is a flowchart of the method provided by the application;

[0020] Figure 2 is a principle block diagram of the device comprising the discharge protection circuit. DETAILED DESCRIPTION

[0021] The application will be further described in detail below in combination with the drawings and examples.

[0022] The application provides a device internal large-capacity capacitor discharge protection method, a discharge protection circuit and a device with device internal large-capacity capacitor discharge protection to solve the problems of insufficient discharge and unreasonable discharge time in the prior art, realize continuous endurance power supply to the external load after the device is powered off, and timely release the remaining power of the energy storage capacitor in the device, thereby avoiding the safety hazards in the process of device storage and transportation.

[0023] In order to realize power supply to the external load, the energy storage capacitor in the device is usually set as a large-capacity capacitor to provide sufficient power. In the specific implementation, the large-capacity capacitor can be set as a large-capacity capacitor group composed of multiple capacitors. The energy storage capacitor can also supply power to the circuit in the device to maintain the operation of the circuit, including power supply to each module of the discharge protection circuit.

[0024] The device internal large-capacity capacitor discharge protection method provided by the application is as shown in Figure 1 The steps are as follows:

[0025] 1) detecting whether the external power supply is powered off, if yes, executing step 2);

[0026] 2) judging whether the power-off duration T exceeds the endurance duration T1 of the energy storage capacitor and whether the real-time power supply voltage V of the energy storage capacitor is lower than the effective working voltage V1 of the external load;

[0027] 3) If T>T1 and V>V1, the discharge switch is controlled to be turned on, and the energy storage capacitor is discharged through the discharge load.

[0028] Based on the discharge protection method, the application provides a large-capacity capacitor discharge protection circuit in a device, as shown in the accompanying drawings, which comprises a power-off detection module, a controller, a capacitor voltage detection module, a discharge switch, a discharge load, an energy storage capacitor, a discharge circuit formed by the energy storage capacitor, the discharge switch and the discharge load, a discharge control circuit formed by the energy storage capacitor, the capacitor voltage detection module, the controller and the discharge switch; and the controller, the capacitor voltage detection module, the discharge switch and the voltage pull-up module are powered by the energy storage capacitor. Figure 2

[0029] With reference to the discharge protection method, in the working process of the discharge protection circuit, after the power-off detection module detects that the external power supply is powered off, the controller performs timing and judges whether the power-off duration T exceeds the endurance duration T1 of the energy storage capacitor, and the capacitor voltage detection module judges whether the real-time power supply voltage V of the energy storage capacitor is lower than the effective working voltage V1 of the external load; if T>T1 and V>V1, the controller controls the discharge switch to be turned on, and the energy storage capacitor is discharged through the discharge load.

[0030] In step 2), the power-off duration is judged and it is ensured that the power-off duration T exceeds the endurance duration T1 of the energy storage capacitor, and the real-time power supply voltage of the energy storage capacitor is judged and it is ensured that the real-time power supply voltage V of the energy storage capacitor is lower than the effective working voltage V1 of the external load, and then internal discharge is performed, so as to enable the energy storage capacitor to supply power to the external load to the maximum extent and ensure that the external load has a long enough normal working duration. The application discharges the energy storage capacitor internally at T>T1 and V>V1, that is, it ensures external power supply and can automatically start discharging at an appropriate time. The application first lays the foundation of automatic discharge, and then provides enough duration and power for the power supply of the external load, balances safety and efficiency, that is, it does not waste energy, meets the working requirements of the external load, and completely avoids the hidden danger of manual discharge.

[0031] ​In the embodiment, the controller is powered by the energy storage capacitor, and the controller needs a supply voltage higher than its minimum working voltage to work, and the discharging switch is controlled by the controller to be turned on and off, that is, the controller inputs control information such as high level to the discharging switch to make the discharging switch turn on and keep normally closed. In order to ensure the effective and continuous discharging, the discharging switch needs to keep normally closed when the controller works or does not work. However, since the supply voltage of the energy storage capacitor gradually decreases during discharging, and when the supply voltage is less than the minimum working voltage of the controller, the controller will be powered off and cannot keep the discharging switch in the on state through the controller, so the energy storage capacitor cannot continue to be discharged. At this time, the real-time supply voltage of the energy storage capacitor is still relatively high, that is, the energy storage capacitor still has a certain amount of residual power. In order to discharge fully, specifically, the control input end of the discharging switch is connected with a voltage pull-up module to provide an enable pull-up voltage to the control input end of the discharging switch; when the real-time supply voltage V of the energy storage capacitor is lower than the minimum working voltage V2 of the controller, the discharging switch keeps normally closed through the enable pull-up voltage. During working, the real-time supply voltage V of the energy storage capacitor is detected in real time, and when the real-time supply voltage V is lower than the minimum working voltage V2 of the controller, the controller is powered off; the voltage pull-up module provides an enable pull-up voltage to the input end of the discharging switch, and the discharging switch keeps normally closed through the enable pull-up voltage. Further, even if the supply voltage of the energy storage capacitor decreases and the controller is powered off, the discharging switch can still keep normally closed to make the discharging load continue to discharge the energy storage capacitor.

[0032] At the same time, in order to prevent the voltage pull-up module from making the discharging switch turn on when the external power source is effectively connected, causing waste of energy, and prevent the problem of heating caused by continuous discharging of the discharging load, in the embodiment, the voltage pull-up module only outputs the enable pull-up voltage meeting the working requirement of the discharging switch when the real-time supply voltage V of the energy storage capacitor meets the working voltage requirement of the voltage pull-up module. Specifically, the working voltage of the voltage pull-up module is set to be lower than the minimum working voltage V2 of the controller, so that when the real-time supply voltage V of the energy storage capacitor is lower than the minimum working voltage V2 of the controller, it meets the working voltage requirement of the voltage pull-up module, and the voltage pull-up module works to output the enable pull-up voltage meeting the working requirement of the discharging switch. Finally, the energy storage capacitor is discharged to a residual power insufficient to drive the discharging switch to turn on, that is, the discharging stops.

[0033] The controller controls the on and off of the discharging switch.

[0034] The controller judges whether the external power source is powered off through the power-off detection module, and then enters the discharging process.

[0035] The discharging load provides a discharging circuit for the energy storage capacitor when the discharging switch is turned on.

[0036] The voltage pull-up module is used to provide an enable pull-up voltage for the discharge switch, so as to realize that the discharge switch keeps on when the controller is out of control.

[0037] When the external power supply is normally connected, the controller controls the discharge switch to be turned off, and the voltage pull-up module does not form an enable pull-up for the discharge switch.

[0038] After the external power supply is turned off, the controller detects the power-off through the power-off detection module and starts timing. At the same time, the voltage of the energy storage capacitor is detected through the capacitor voltage detection module.

[0039] Based on the discharge protection circuit, the application further provides a device with large-capacity capacitor discharge protection, such as Figure 2 As shown, the device comprises a charging module, an energy storage capacitor, and a discharge protection circuit. The charging module is connected with the energy storage capacitor and the capacitor voltage detection module of the discharge protection circuit. The energy storage capacitor supplies power for the controller, the capacitor voltage detection module, the discharge switch, and the voltage pull-up module of the discharge protection circuit. The device based on the discharge protection method provides discharge protection after the external power supply is turned off.

[0040] The external power supply provides working power for the device.

[0041] When the external power supply is normally connected, the energy storage capacitor is charged through the charging module.

[0042] The above embodiments are only used to illustrate the application, and are not used as a limitation on the application. As long as the technical essence of the application is followed, changes, modifications, etc. of the above embodiments will fall within the scope of the claims of the application.

Claims

1. A method for protecting a large capacity capacitor in a device from discharging, comprising: The steps are as follows: 1) detecting whether the external power supply is powered off, if yes, executing step 2); 2) judging whether the power-off duration T exceeds the energy storage capacitor endurance duration T1, and judging whether the real-time power supply voltage V of the energy storage capacitor is lower than the effective working voltage V1 of the external load; 3) if T>T1 and V>V1, the controller controls the discharge switch to be turned on, and the energy storage capacitor is discharged through the discharge load; 4) the real-time power supply voltage V of the energy storage capacitor is detected in real time, when the real-time power supply voltage V is lower than the minimum working voltage V2 of the controller, the controller is powered off and turned off; the voltage pull-up module provides an enable pull-up voltage to the input end of the discharge switch, and the discharge switch keeps a normally closed state through the enable pull-up voltage.

2. A large capacity capacitor discharge protection circuit in a device, characterized by, The discharge protection circuit comprises a power-off detection module, a controller, a capacitor voltage detection module, a discharge switch, a discharge load, the energy storage capacitor and the discharge switch and the discharge load form a discharge loop, and the energy storage capacitor and the capacitor voltage detection module, the controller and the discharge switch form a discharge control loop. After the power-off detection module detects that the external power supply is powered off, the controller performs timing, and judges whether the power-off duration T exceeds the energy storage capacitor endurance duration T1, and the capacitor voltage detection module judges whether the real-time power supply voltage V of the energy storage capacitor is lower than the effective working voltage V1 of the external load; if T>T1 and V>V1, the controller controls the discharge switch to be turned on, and the energy storage capacitor is discharged through the discharge load; the control input end of the discharge switch is connected with a voltage pull-up module, and the control input end of the discharge switch is provided with an enable pull-up voltage; when the real-time power supply voltage V of the energy storage capacitor is lower than the minimum working voltage V2 of the controller, the discharge switch keeps a normally closed state through the enable pull-up voltage.

3. An apparatus having in-apparatus large-capacity capacitor discharge protection, characterized by comprising: The discharge protection circuit comprises a charging module, an energy storage capacitor and the discharge protection circuit of claim 2, and the charging module is connected with the energy storage capacitor and the capacitor voltage detection module of the discharge protection circuit respectively.

4. The device with in-device large-capacity capacitor discharge protection of claim 3, wherein, The energy storage capacitor supplies power for the controller, the capacitor voltage detection module, the discharge switch and the voltage pull-up module of the discharge protection circuit.

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