Power failure energy storage protection system and method

Abstract

The invention provides a power-down energy storage protection system and method, and the system comprises a micro-control unit MCU which is used for detecting the power supply state of a system power supply unit; the first MOS tube is connected between the system power supply unit and the load circuit and is connected with the micro-control unit MCU and the super capacitor, and the micro-control unit MCU controls the working state of the first MOS tube according to the power supply state; the second MOS tube is connected between the super capacitor and the load circuit and is connected with the micro-control unit MCU, and the micro-control unit MCU controls the working state of the second MOS tube according to the power supply state; and the super capacitor is used for supplying power to the load circuit and the MCU when the power supply state is a power-down state. According to the invention, the MOS tube is adopted to replace a diode to realize a power supply isolation function, and the voltage drop caused by power supply isolation is greatly reduced.

Description

Technical Field

[0001] The present application relates to the field of power supply and distribution technology, and in particular to a power-off energy storage protection system and method. Background Art

[0002] With the advent of the big data era, intelligent instruments and equipment are becoming more and more popular, and data storage is becoming more and more important for individuals and enterprises. At the same time, ensuring that the system preserves data when the power is off has become an issue that users are increasingly concerned about.

[0003] At present, the use of supercapacitors for power-off energy storage protection is a common solution. The existing energy storage design using supercapacitors mainly consists of three parts: power-off monitoring circuit, efficiency improvement circuit and charge and discharge control circuit, such as Figure 1 As shown. The power-off monitoring circuit is to promptly notify the MCU to execute the file saving action when the system power supply is cut off. The efficiency improvement circuit can convert the output voltage of the supercapacitor to the normal voltage value required for the device to work. The charge and discharge control circuit can complete the charge and discharge monitoring of the supercapacitor, and when the system power supply is cut off, it will switch to the supercapacitor circuit side in time to supply power to the subsequent load. The specific working process is as follows:

[0004] The system power supply supplies power to the load circuit on the one hand, and charges the supercapacitor on the other hand. The diode can be used to prevent the supercapacitor from reverse power supply. When the supercapacitor is charged to the rated value, the charge and discharge control circuit cuts off the channel for charging the supercapacitor. At this time, the supercapacitor does not participate in the normal power supply of the system as a backup energy storage power supply. When the system power supply is cut off (this state is monitored by the power-off monitoring circuit, and a power-off signal is sent to the microcontroller unit MCU), at this time, the charge and discharge control circuit switches the power supply channel of the load circuit to the supercapacitor side. The supercapacitor supplies power to the load circuit through the efficiency improvement circuit (usually the BOOST circuit), thereby realizing the power supply protection of the system. After the power supply is completed, the residual voltage on the supercapacitor is released through the discharge resistor.

[0005] In this scheme, in order to prevent the supercapacitor from reverse power supply, a diode is added to the front end of the supercapacitor to isolate the power supply. However, due to the certain voltage drop of the diode, the power supply output efficiency will be reduced to a certain extent. In addition, after the load circuit completes the action of saving data, there is still residual voltage on the supercapacitor, which will cause the voltage on the load circuit to drop slowly. At the same time, the current provided by the supercapacitor is also increasing, which will burn the service life of the circuit in the long run. In addition, the use of a bleeder resistor for voltage discharge requires a reasonable selection of the resistance of the bleeder resistor. If the resistance of the selected bleeder resistor is small, the discharge current will be too large due to the excessive capacitance of the supercapacitor. The ordinary group is difficult to withstand such a high power, increasing the design and development cost. If the resistance of the selected bleeder resistor is large, the voltage on the supercapacitor is discharged very slowly, and the discharge time is long. It is difficult to ensure that the power supply will not be restored before the voltage discharges to a safe voltage. If the power switch is reconnected during the power-off period, the load circuit is restarted without completely losing power, which will also cause the circuit to fail to reset and start normally, and then cause abnormal circuit operation, such as a power-on crash. Some devices that have strict requirements for power-on timing will not be able to start normally, and there is no way to warn of abnormal device startup. Therefore, the existing power-off energy storage protection design lacks reliability. Summary of the invention

[0006] In order to solve one of the above technical defects, a power-off energy storage protection system and method are provided in an embodiment of the present application.

[0007] A first aspect of an embodiment of the present application provides a power-off energy storage protection system, the system comprising:

[0008] A microcontroller unit MCU is used to detect the power supply status of the system power supply unit;

[0009] A first MOS tube is connected between the system power supply unit and the load circuit, and is connected to a micro control unit MCU and a super capacitor, and the micro control unit MCU controls the working state of the first MOS tube according to the power supply state;

[0010] A second MOS tube is connected between the super capacitor and the load circuit, and is connected to a micro control unit MCU, and the micro control unit MCU controls the working state of the second MOS tube according to the power supply state;

[0011] The super capacitor is used to supply power to the load circuit and the micro control unit MCU when the power supply state is a power-off state.

[0012] A second aspect of the embodiment of the present application provides a power-off energy storage protection method, which is applied to the power-off energy storage protection system described in the first aspect of the embodiment of the present application, and the method includes:

[0013] The microcontroller unit MCU detects the power supply status of the system power supply unit;

[0014] When the power supply state is a normal power supply state, the micro control unit MCU controls the first MOS tube to be turned on and the second MOS tube to be turned on, and the system power supply unit supplies power to the micro control unit MCU, the load circuit and the super capacitor respectively;

[0015] When the power supply state is a power-off state, the micro control unit MCU controls the first MOS tube to turn off, and controls the second MOS tube to turn on, and starts the power-off timing at the same time, and the super capacitor supplies power to the micro control unit MCU and the load circuit respectively;

[0016] When the power-off timing reaches a first preset time, the micro control unit MCU controls the second MOS tube to turn off, and the super capacitor supplies power to the micro control unit MCU.

[0017] The power-off energy storage protection system and method provided in the embodiment of the present application are adopted, and MOS tubes are used instead of diodes to realize the function of power isolation. The MOS tube is controlled by the microcontroller unit MCU to turn on and off, which greatly reduces the voltage drop caused by power isolation and improves the utilization efficiency of the power supply. At the same time, a MOS tube is also added on the supercapacitor side to realize the management function of the backup power supply. After the load circuit data backup is completed, the microcontroller unit MCU controls the MOS tube to turn off, avoiding unnecessary discharge of the supercapacitor and extending the service life of the supercapacitor. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0019] Figure 1 It is a schematic diagram of the principle of the existing power-off energy storage protection system;

[0020] Figure 2 This is a schematic diagram of the principle of the power-off energy storage protection system described in Example 1 of the present application. DETAILED DESCRIPTION

[0021] In order to make the technical solutions and advantages in the embodiments of the present application more clearly understood, the exemplary embodiments of the present application are further described in detail below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present application, rather than an exhaustive list of all the embodiments. It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict.

[0022] Example 1

[0023] like Figure 2 As shown, this embodiment proposes a power-off energy storage protection system, which is arranged between the system power supply unit and the load circuit, and is used for power-off energy storage protection when the power supply system is in a power-off state. The system includes a microcontroller unit MCU, a first MOS tube, a second MOS tube and a supercapacitor. The first MOS tube is arranged between the system power supply unit and the load circuit, and is connected to the supercapacitor and the microcontroller unit MCU. The supercapacitor and the second MOS tube are connected between the system power supply unit and the load circuit as a backup power supply. The microcontroller unit MCU can control the gates of the first MOS tube and the second MOS tube to control their working states.

[0024] Specifically, in this embodiment, the system power supply unit supplies power to the load circuit and the micro control unit MCU via the first MOS tube, wherein the body diode direction of the first MOS tube is the same as the power supply current direction of the system power supply unit. The micro control unit MCU can detect the current power supply state of the entire system through the power supply voltage of the system power supply unit. A super capacitor is connected to the output end of the first MOS tube, and at the same time, the super capacitor is connected to the load circuit via the second MOS tube, wherein the body diode direction of the second MOS tube is opposite to the power supply current direction of the system power supply unit. The micro control unit MCU can control the working state of the first MOS tube and the second MOS tube through the detected power supply state, and then switch the power supply mode.

[0025] In this embodiment, the power supply state detected by the microcontroller unit MCU is mainly divided into a normal power supply state and a power-off state. In the normal power supply state, the microcontroller unit MCU controls the first MOS tube and the second MOS tube to be turned on, so that the system power supply unit can supply power to the load circuit and the supercapacitor. In addition, since the direction of the body diode of the first MOS tube is consistent with the direction of the power supply current of the system power supply unit, the power supply current of the supercapacitor can be prevented from flowing back. In the power-off state, the microcontroller unit MCU controls the first MOS tube to be turned off, thereby cutting off the power supply between the system power supply unit and the load circuit. At the same time, the microcontroller unit MCU controls the second MOS tube to be turned on, the supercapacitor continues to supply power to the load circuit, and completes the data backup of the load circuit.

[0026] This embodiment uses MOS tubes instead of diodes to achieve the function of power isolation. The microcontroller unit MCU controls the on / off and off of the MOS tube, which greatly reduces the voltage drop caused by power isolation and improves the utilization efficiency of the power supply. At the same time, a MOS tube is also added on the supercapacitor side to achieve the management function of the backup power supply.

[0027] In some optional embodiments, when the power supply state is a power-off state, the micro control unit MCU is further configured to start a power-off timing, and control a working state of the second MOS tube when the power-off timing ends.

[0028] Specifically, after the data backup of the load circuit is completed, the microcontroller unit MCU controls the second MOS tube to turn off, cutting off the power supply between the supercapacitor and the load circuit. At this time, the supercapacitor only supplies power to the microcontroller unit MCU, avoiding unnecessary discharge of the supercapacitor and extending the service life of the supercapacitor. In addition, since the power supply of the load circuit has been completely cut off, the problem of startup failure of the load device due to abnormal power-on timing will not occur when the external power is turned on again at this time.

[0029] In some optional embodiments, the micro control unit MCU is connected to the load circuit, and is used to obtain a working state signal sent by the load circuit, and control the working state of the second MOS tube according to the working state signal.

[0030] Specifically, in this embodiment, a polling operation is added between the microcontroller unit MCU and the load circuit. The main control processor of the load circuit can always send a polling signal to the MCU, indicating that the load circuit is working normally. If the microcontroller unit MCU does not receive the polling signal within a period of time, it means that there is an abnormality in the current load circuit, and the abnormality problem can be solved by closing the second MOS tube and reopening it, which is equivalent to restarting the load circuit. If the microcontroller unit MCU still does not receive the polling signal after the load circuit is restarted, an alarm signal is sent through the microcontroller unit MCU to remind the technician to repair it in time.

[0031] Example 2

[0032] This embodiment provides a power-off energy storage protection method, which can be applied to the following power-off energy storage protection system, which includes:

[0033] A microcontroller unit MCU is used to detect the power supply status of the system power supply unit;

[0034] A first MOS tube is connected between the system power supply unit and the load circuit, and is connected to a micro control unit MCU and a super capacitor, and the micro control unit MCU controls the working state of the first MOS tube according to the power supply state;

[0035] A second MOS tube is connected between the super capacitor and the load circuit, and is connected to a micro control unit MCU, and the micro control unit MCU controls the working state of the second MOS tube according to the power supply state;

[0036] The super capacitor is used to supply power to the load circuit and the micro control unit MCU when the power supply state is a power-off state.

[0037] The specific principle of the power-off energy storage protection system can refer to the content recorded in Example 1, and this embodiment will not be repeated. The power-off energy storage protection method of the power-off energy storage protection system includes:

[0038] The microcontroller unit MCU detects the power supply status of the system power supply unit;

[0039] When the power supply state is a normal power supply state, the micro control unit MCU controls the first MOS tube to be turned on and the second MOS tube to be turned on, and the system power supply unit supplies power to the micro control unit MCU, the load circuit and the super capacitor respectively;

[0040] When the power supply state is a power-off state, the micro control unit MCU controls the first MOS tube to turn off, and controls the second MOS tube to turn on, and starts the power-off timing at the same time, and the super capacitor supplies power to the micro control unit MCU and the load circuit respectively;

[0041] When the power-off timing reaches a first preset time, the micro control unit MCU controls the second MOS tube to turn off, and the super capacitor supplies power to the micro control unit MCU.

[0042] Specifically, in the present embodiment, a first MOS tube is arranged between the system power supply unit and the load circuit. The body diode direction of the first MOS tube is consistent with the power supply current direction of the system power supply unit, which can effectively prevent the power supply current of the super capacitor from flowing back. When the system power supply unit normally supplies power to the load circuit, the gate of the first MOS tube is controlled by the microcontroller unit MCU to turn on the first MOS tube. At this time, the first MOS tube can be regarded as an ideal diode, and the voltage drop on the first MOS tube can be ignored. In the process of the system power supply unit supplying power to the load circuit normally, the microcontroller unit MCU always keeps monitoring the power supply voltage of the system power supply unit. Once it is detected that the power supply voltage of the system power supply unit is less than the preset voltage, the algorithm program embedded in the microcontroller unit MCU can determine that the current power supply state is a power-off state. At this time, the microcontroller unit MCU controls the first MOS tube to be turned off.

[0043] A second MOS tube is arranged between the supercapacitor and the load circuit. The body diode direction of the second MOS tube is opposite to the power supply current direction of the system power supply unit. When the system power supply unit supplies power to the load circuit, the microcontroller unit MCU controls the second MOS tube to be turned on. At this time, the system power supply unit is charging the supercapacitor while supplying power to the load circuit. When the microcontroller unit MCU detects that the current power supply state is a power-off state, the microcontroller unit MCU starts the power-off timing. Since the microcontroller unit MCU simultaneously controls the first MOS tube to be turned off in the power-off state, the load circuit is powered by the supercapacitor. When the power-off timing reaches the first preset time, the microcontroller unit MCU controls the second MOS tube to be turned off, and at this time the supercapacitor only retains the power supply to the microcontroller unit MCU. Since the microcontroller unit MCU has low power consumption, the remaining voltage of the supercapacitor after supplying power to the load circuit can still maintain the microcontroller unit MCU to work for a period of time. And since the power supply to the load circuit has been completely cut off at this time, the problem of startup failure of the load device due to abnormal power-on timing will not occur when the load circuit is re-stored externally at this time.

[0044] In some optional embodiments, the first preset time may be determined according to the time required for the microcontroller unit MCU to back up the load circuit data. That is, when the microcontroller unit MCU completes backing up the load circuit data, the supercapacitor immediately cuts off the power supply to the load circuit, thereby avoiding unnecessary power loss and increasing the service life of the supercapacitor.

[0045] In some optional embodiments, the power-off energy storage protection method proposed in this embodiment also includes a process in which the micro control unit MCU receives a polling signal sent by the load circuit.

[0046] Specifically, the load circuit sends a working status signal to the microcontroller unit MCU according to a preset frequency. When the microcontroller unit MCU does not receive the working status signal sent by the load circuit within a second preset time (which can be set according to actual conditions), the microcontroller unit MCU controls the second MOS tube to turn off, and then controls the second MOS tube to turn on, which is equivalent to restarting the load circuit, thereby solving the problem of abnormal startup of the load device in the load circuit.

[0047] In some optional embodiments, after restarting the load circuit, if the microcontroller unit MCU still does not receive the working status signal sent by the load circuit within the second preset time range, it can be located that there is an abnormality in the load circuit, and an alarm signal is sent through the microcontroller unit MCU to remind technicians to perform maintenance work in time.

[0048] In this application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or can communicate with each other; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0049] Although the preferred embodiments of the present application have been described, those skilled in the art may make other changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications falling within the scope of the present application.

[0050] Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include these modifications and variations.

Claims

1. A power-off energy storage protection system, characterized in that: The system comprises: A microcontroller unit MCU is used to detect the power supply status of the system power supply unit; A first MOS tube is connected between the system power supply unit and the load circuit, and is connected to a micro control unit MCU and a super capacitor, and the micro control unit MCU controls the working state of the first MOS tube according to the power supply state; A second MOS tube is connected between the super capacitor and the load circuit, and is connected to a micro control unit MCU, and the micro control unit MCU controls the working state of the second MOS tube according to the power supply state; The super capacitor is used to supply power to the load circuit and the micro control unit MCU when the power supply state is a power-off state.

2. The system according to claim 1, characterized in that The direction of the body diode of the first MOS tube is the same as the direction of the power supply current of the system power supply unit.

3. The system according to claim 1, characterized in that The direction of the body diode of the second MOS tube is opposite to the direction of the power supply current of the system power supply unit.

4. The system according to claim 1, characterized in that When the power supply state is a power-off state, the micro control unit MCU is further used to start a power-off timing, and when the power-off timing ends, control the working state of the second MOS tube.

5. The system according to claim 1, characterized in that The micro control unit MCU is connected to the load circuit, and is used to obtain a working state signal sent by the load circuit, and control the working state of the second MOS tube according to the working state signal.

6. The power-off energy storage protection method of the power-off energy storage protection system according to any one of claims 1 to 5, characterized in that: The method comprises: The microcontroller unit MCU detects the power supply status of the system power supply unit; When the power supply state is a normal power supply state, the micro control unit MCU controls the first MOS tube to be turned on and the second MOS tube to be turned on, and the system power supply unit supplies power to the micro control unit MCU, the load circuit and the super capacitor respectively; When the power supply state is a power-off state, the micro control unit MCU controls the first MOS tube to turn off, and controls the second MOS tube to turn on, and starts the power-off timing at the same time, and the super capacitor supplies power to the micro control unit MCU and the load circuit respectively; When the power-off timing reaches a first preset time, the micro control unit MCU controls the second MOS tube to turn off, and the super capacitor supplies power to the micro control unit MCU.

7. The method according to claim 6, characterized in that The process of the microcontroller unit MCU detecting the power supply status of the system power supply unit includes: The microcontroller unit MCU obtains the power supply voltage of the system power supply unit; comparing the supply voltage with a preset voltage; When the power supply voltage is greater than or equal to the preset voltage, the power supply state is a normal power supply state; When the supply voltage is less than the preset voltage, the power supply state is a power-off state.

8. The method according to claim 7, characterized in that The first preset time is the time required for the micro control unit MCU to back up the load circuit data.

9. The method according to claim 6, characterized in that The method further comprises: The load circuit sends a working status signal to the microcontroller unit MCU according to a preset frequency; When the micro control unit MCU does not receive the working state signal sent by the load circuit within the second preset time range, the micro control unit MCU controls the second MOS tube to turn off, and then controls the second MOS tube to turn on.

10. The method according to claim 9, characterized in that The method further comprises: When the micro control unit MCU controls the second MOS tube to turn off and then controls the second MOS tube to turn on, if the micro control unit MCU does not receive the working state signal sent by the load circuit within a second preset time range, the micro control unit MCU sends an alarm signal.

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