Power management system and energy storage device

Abstract

The utility model discloses a power supply management system and an energy storage device, and the power supply management system is arranged between a main power supply and at least one load, and comprises a power supply state monitoring circuit, a standby power supply, a power supply switching circuit, a control circuit, and at least one electric energy output switching circuit. The power supply switching circuit is used for supplying power to the load based on the standby power supply when the main power supply stops outputting electric energy. The control circuit is used for identifying whether each load is in a working state, and when a certain load is identified to be in a non-working state and power is supplied based on the standby power supply, the control circuit controls the electric energy output switch circuit to disconnect the circuit connection between the load in the non-working state and the standby power supply so as to stop supplying power to the load in the non-working state. According to the technical scheme disclosed by the utility model, when the standby power supply works, the power supply circuit of the load in the non-working state is cut off, so that the electric quantity in the standby power supply is saved, the power supply time of the standby power supply is prolonged, and the power supply stability of the load in the working state is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of power management, in particular to a power management system and an energy storage device. Background Art

[0002] At present, new energy photovoltaic and energy storage systems are being used more and more widely in power systems. When new energy photovoltaic and energy storage systems are in operation, control equipment is needed to perform online monitoring, data storage and scheduling of new energy photovoltaic and energy storage systems. However, during the operation of the control equipment, abnormal power outages often occur, resulting in the inability to save data information such as operation data, fault data, system status data in the control equipment, and thus the inability to analyze the cause of the abnormal power outage.

[0003] To solve the above problems, a backup power supply is usually used to provide backup power for the above control devices. There are two common ways to set up the backup power supply. One is to use an external uninterruptible power supply (UPS) as a backup power supply, but this method is very expensive and requires a large installation space in the control device, which makes installation inconvenient; the other is to set up a backup power supply inside the control device to power the loads that perform different tasks in the control device; but although this method reduces the cost and product size of the control device compared to the uninterruptible power supply (UPS), there are still some problems: the control device contains multiple loads, and in the process of online monitoring, data storage and scheduling of new energy photovoltaic and energy storage systems, each load is compatible with different application scenarios, resulting in a large number of loads in the control device. However, for a specific scenario, only part of the load needs to be in working state. However, due to the diversity of usage scenarios, there is a great deal of randomness in the loads that need to be in a working state, resulting in a large number of non-working loads in the control device, and limited by the limited space inside the control device and the small capacity of the backup power supply, when power is supplied to each load in a working state and a non-working state through the power supply interface, the power of the backup power supply will be quickly exhausted, resulting in poor power supply stability for the loads in a working state in the control device. Utility Model Content

[0004] In view of this, the utility model provides a power management system and an energy storage device, the main purpose of which is to solve the technical problem of poor power supply stability for loads that need to be in a working state in control equipment that performs online monitoring, data storage and scheduling of new energy photovoltaic and energy storage systems.

[0005] To achieve the above object, the utility model first provides a power management system, which is arranged between a main power supply and at least one load, and the power management system includes a power state monitoring circuit, a backup power supply, a power switching circuit, a control circuit and at least one power output switch circuit, wherein:

[0006] The power supply status monitoring circuit is connected to the main power supply and is used to output a backup power supply operation signal to the control circuit when it is detected that the main power supply does not output power;

[0007] The first access end of the power switching circuit is connected to the main power supply, the second access end of the power switching circuit is connected to the backup power supply, and the output end of the power switching circuit is connected to the input end of each of the power output switch circuits, so as to connect the backup power supply to each of the power output switch circuits when the main power supply does not output power;

[0008] The output end of the power output switch circuit is connected to the load in a one-to-one correspondence, and the controlled end of the power output switch circuit is connected to the control circuit, and is used to control the power output switch circuit to be in an on state or an off state;

[0009] The control circuit is used to determine whether the load connected to each of the power output switch circuits is in a non-working state when receiving the backup power supply operation signal, and control the power output switch circuit connected to the non-working load to be in a disconnected state.

[0010] In one embodiment of the utility model, the electric energy output switching circuit includes a switching circuit and a first resistor; the input end of the switching circuit is connected to the output end of the power switching circuit, the output end of the switching circuit is connected to the first end of the first resistor, and the controlled end of the switching circuit is connected to the control circuit for being controlled to be in an on state or an off state; the second end of the first resistor is connected to the power access end of the load, and the first end of the first resistor and the second end of the first resistor are also respectively connected to the control circuit for enabling the control circuit to determine whether the load is in a working state based on the voltage value across the first resistor.

[0011] In one embodiment of the utility model, the switching circuit includes a field effect transistor, a second resistor and a third resistor; the first end of the second resistor is connected to the control circuit as the controlled end of the switching circuit, and the second end of the second resistor is respectively connected to the gate of the field effect transistor and the first end of the third resistor; the connection end after the second end of the third resistor is connected to the source of the field effect transistor is connected to the output end of the power switching circuit as the input end of the switching circuit, and the drain of the field effect transistor is connected to the first end of the first resistor.

[0012] In one embodiment of the utility model, the power status monitoring circuit includes a fourth resistor and a fifth resistor; the first end of the fourth resistor is connected to the output end of the main power supply, the second end of the fourth resistor is connected to the first end of the fifth resistor, and the second end of the fifth resistor is grounded: the connection end between the fourth resistor and the fifth resistor is connected to the control circuit, for sending the backup power supply operation signal to the control circuit.

[0013] In one embodiment of the utility model, the power switching circuit includes a sixth resistor, a first diode and a second diode; the anode end of the first diode is connected to the output end of the main power supply, the cathode end of the first diode is respectively connected to the input end of the power output switching circuit, the cathode end of the second diode and the first end of the sixth resistor, and the anode end of the second diode and the second end of the sixth resistor are connected to the power output end of the backup power supply.

[0014] In one embodiment of the utility model, the backup power supply is an energy storage capacitor; the backup power supply is an energy storage capacitor; the positive terminal of the energy storage capacitor is connected to the second access terminal of the power switching circuit, and the negative terminal of the energy storage capacitor is grounded.

[0015] In one embodiment of the utility model, the control circuit includes a plurality of control subcircuits, and the control subcircuits correspond to the power output switch circuits one by one; a signal receiving end of the control subcircuit is connected to the power state monitoring circuit, and is used to receive the backup power supply operation signal; a first voltage receiving end of the control subcircuit is connected to a first end of a first resistor of the power output switch circuit connected to the control subcircuit, and a second voltage receiving end of the control subcircuit is connected to a second end of the first resistor, and is used to determine whether a load connected to the power output switch circuit is in a non-working state based on a voltage across the first resistor; a control output end of the control subcircuit is connected to a controlled end of a switch circuit of the power output switch circuit, and is used to control the switch circuit to be in a disconnected state when the backup power supply operation signal is received and it is determined that the load connected to the power output switch circuit is in a non-working state.

[0016] In one embodiment of the utility model, the control subcircuit includes a differential operational amplifier circuit, a latch, an inverter and a pull-up resistor; the first access end of the differential operational amplifier circuit is connected to the first end of the first resistor of the power output switch circuit connected to the control subcircuit, the second access end of the differential operational amplifier circuit is connected to the second end of the first resistor, and the output end of the differential operational amplifier circuit is connected to the input end of the latch, for sending a latch signal to the latch; the output end of the latch is respectively connected to the first end of the pull-up resistor and the input end of the inverter, the output end of the inverter is connected to the controlled end of the switch circuit of the power output switch circuit, and the second end of the pull-up resistor is connected to an external power supply; the latch end of the latch and the enable end of the latch are respectively connected to the power state monitoring circuit, for receiving the backup power operation signal, and when receiving the low-level backup power operation signal, the latch signal is sent to the input end of the inverter.

[0017] In one embodiment of the utility model, the differential operational amplifier circuit includes a seventh resistor, an eighth resistor, a ninth resistor, a tenth resistor and a differential operational amplifier; the first end of the seventh resistor is connected to the first end of the first resistor, the second end of the seventh resistor is connected to the first voltage access terminal of the differential operational amplifier, the first end of the eighth resistor is connected to the second end of the first resistor, the second end of the eighth resistor is respectively connected to the second voltage access terminal of the differential operational amplifier and the first end of the ninth resistor, and the second end of the ninth resistor is grounded; the output end of the differential operational amplifier is connected to the input end of the latch as the output end of the differential operational amplifier circuit, and the tenth resistor is connected in parallel between the first voltage access terminal of the differential operational amplifier and the output end of the differential operational amplifier.

[0018] In addition, to achieve the above-mentioned purpose, the present invention also proposes an energy storage device, including the power management system as mentioned above.

[0019] The utility model provides a power management system and energy storage device, which can supply power to each load in the control device based on the main power supply when the main power supply is in working state; when the main power supply is disabled, the power switching circuit can access the backup power supply to supply power to each working load; further, when the main power supply is disabled, the control circuit can identify whether each load is in working state, and when the load in non-working state is identified, the power output switch circuit connected to the load in non-working state is controlled to disconnect, so as to disconnect the circuit connection between the load in non-working state and the backup power supply, so as to stop supplying power to the load in non-working state based on the backup power supply. The technical solution disclosed by the utility model can cut off the power supply circuit of the load in non-working state when the backup power supply is working, so as to save the power in the backup power supply, improve the power supply time of the backup power supply, and improve the power supply stability to the load in working state.

[0020] The above description is only an overview of the technical solution of the utility model. In order to more clearly understand the technical means of the utility model, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the utility model more obvious and easy to understand, the specific implementation methods of the utility model are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation on the present invention. In the drawings:

[0022] Figure 1 A schematic diagram of the structure of a power management system provided by an embodiment of the utility model is shown;

[0023] Figure 2 A schematic diagram of the structure of another power management system provided by an embodiment of the utility model is shown;

[0024] Figure 3 A schematic diagram of the structure of a switch circuit provided by an embodiment of the utility model is shown;

[0025] Figure 4 A structural schematic diagram of a control subcircuit provided in an embodiment of the utility model is shown. DETAILED DESCRIPTION

[0026] The present invention will be described in detail below with reference to the accompanying drawings and in combination with embodiments. It should be noted that the embodiments and features in the embodiments of the present invention can be combined with each other without conflict.

[0027] In order to further explain the technical means and effects adopted by the utility model to achieve the predetermined utility model purpose, the specific implementation methods, structures, features and effects of the utility model application are described in detail below in conjunction with the accompanying drawings and preferred embodiments. In the following description, different "one embodiment" or "embodiment" does not necessarily refer to the same embodiment. In addition, specific features, structures, or characteristics in one or more embodiments may be combined in any suitable form.

[0028] Combine the following Figures 1 to 4 A power management system and an energy storage device according to some embodiments of the present invention are described.

[0029] like Figure 1 As shown, a power management system proposed in one embodiment of the utility model is arranged between the main power supply and at least one load, including a power state monitoring circuit, a backup power supply, a power switching circuit, a control circuit and at least one power output switch circuit, the number of the power output switch circuits is the same as the number of loads, and each power output switch circuit is connected to a load to correspond to the loads one by one. Among them, the load is a power module used to perform different functions in the control device for online monitoring, data storage and scheduling of new energy photovoltaic and energy storage systems, and each load is connected to the main power supply through the power supply interface, the power switching circuit and the power output switch circuit to obtain power.

[0030] Specifically, the power status monitoring circuit is connected to the main power supply, and is used to output a backup power supply operation signal to the control circuit when it is detected that the main power supply is not outputting electric energy; here, the power status monitoring circuit can identify whether the main power supply outputs a working current or voltage to determine whether the main power supply stops outputting electric energy, and when the main power supply stops outputting a working current or voltage, it outputs a low-level signal as a backup power supply operation signal to the control circuit connected to the power status monitoring circuit to indicate the working status of the main power supply to the control circuit, and when the control circuit receives the backup power supply operation signal, it can be determined that the main power supply is not outputting electric energy.

[0031] Furthermore, the first access end of the power switching circuit is connected to the main power supply, the second access end of the power switching circuit is connected to the backup power supply, and the output end of the power switching circuit is connected to the input end of each of the power output switching circuits, so as to connect the backup power supply to each of the power output switching circuits when the main power supply does not output power. Here, the power switching circuit can monitor whether the main power supply outputs voltage or current. When the main power supply outputs voltage or current, the power switching circuit conducts between the first access end of the power switching circuit and the output end of the power switching circuit, so that the power output of the main power supply can be provided to the load through each power output switching circuit. Conversely, when the main power supply stops outputting voltage or current, the power switching circuit conducts between the second access end of the power switching circuit and the output end of the power switching circuit, so that the power output of the backup power supply can be provided to the load through each power output switching circuit.

[0032] Furthermore, the output end of the power output switch circuit is connected to the load in a one-to-one correspondence, and the controlled end of the power output switch circuit is also connected to the control circuit, for being controlled to make the power output switch circuit in an on state or an off state; wherein the output end of the power output switch circuit is connected to the power supply interface of the load to supply power to the load. Specifically, the power output switch circuit is connected between the power supply interface of the load and the output end of the power switching circuit, and the power output switch circuit can be controlled by the control circuit to be in an on or off state, so that the circuit between the connected load and the output end of the power switching circuit is in an on or off state, thereby making the circuit connection between the load connected to the power output switch circuit and the main power supply or the backup power supply in an on or off state.

[0033] Further, the control circuit is used to determine whether the load connected to each of the power output switch circuits is in a non-working state when receiving the backup power supply operation signal, and control the power output switch circuit connected to the non-working load to be in a disconnected state. Specifically, when the control circuit receives the backup power supply operation signal, it can be determined that the main power supply is not outputting power, and the backup power supply is currently supplying power to the load; further, the control circuit can be connected to a current sensor arranged on the power output switch circuit to determine whether there is current input to the load on the power output switch circuit. When there is current on the power output switch circuit, it can be determined that the load connected to the power output switch circuit is in a working state. When there is no current on the power output switch circuit, it can be determined that the load connected to the power output switch circuit is not in a working state. Further, when the load connected to the power output switch circuit is not in a working state, the control circuit can control the power output switch circuit to be disconnected, so as to disconnect the circuit connection between the load that is not in a working state and the backup power supply, and prevent the load that is not in a working state from consuming the power in the backup power supply.

[0034] It should be noted that the selection of the power status monitoring circuit, the backup power supply, the power switching circuit, the control circuit and the power output switch circuit and the internal circuit connection method can be determined according to the actual situation, and this embodiment does not make specific restrictions. In addition, the connection method of each device can be determined according to the specific selection of the device, and this embodiment does not make specific restrictions. The circuit function of the power management system provided in this embodiment is mainly realized through the circuit connection relationship between each circuit module, and does not rely on the program module in a certain circuit module. In addition, each circuit module in the power management system can be realized by an analog circuit or a digital circuit, and for the circuit module that can be implanted with a program module, the realization of its module function can be realized by the program module provided by the prior art.

[0035] In a power management system provided by the utility model, when the main power supply is in working state, each load in the control device can be powered based on the main power supply; when the main power supply is disabled, the power switching circuit can access the auxiliary power supply to power each working load; further, when the main power supply is disabled, the control circuit can identify whether each load is in working state, and when the load in non-working state is identified, the power output switch circuit connected to the load in non-working state is controlled to disconnect, so as to disconnect the circuit connection between the load in non-working state and the backup power supply, so as to stop supplying power to the load in non-working state based on the backup power supply. The technical solution disclosed by the utility model can shut down the power supply circuit that supplies power to the load in non-working state when the backup power supply is working, so as to save the electric energy in the backup power supply and improve the power supply stability to the load in working state.

[0036] In one embodiment, Figure 2 As shown, the electric energy output switch circuit includes a switch circuit and a first resistor R1; wherein the switch circuit can be controlled to be in an on or off state.

[0037] Specifically, the input end of the switch circuit is connected to the output end of the power switching circuit, the output end of the switch circuit is connected to the first end of the first resistor R1, and the controlled end of the switch circuit is connected to the control circuit for being controlled to be in an on state or an off state.

[0038] Furthermore, the second end of the first resistor R1 is connected to the power access end of the load to supply power to the load, and the first end of the first resistor R1 and the second end of the first resistor R2 are also respectively connected to the control circuit so that the control circuit determines whether the load is in a working state based on the voltage value across the first resistor R1.

[0039] Here, when the load is in a working state, a large amount of current will flow into the first resistor R1, resulting in a voltage signal generated at both ends of the first resistor R1. At the same time, because the first resistor R1 has resistance, a voltage difference will be generated between the voltage signals generated at both ends of the first resistor R1. When the control circuit recognizes the voltage difference from both ends of the first resistor R1, it can be determined that the load connected to the first resistor R1 is in a working state; conversely, when the load is in a non-working state, the current flowing through the first resistor R1 is small or there is no current, resulting in no identifiable voltage difference between the voltage signals generated at both ends of the first resistor R1. When the control circuit cannot recognize the voltage difference from both ends of the first resistor R1, it can be determined that the load connected to the first resistor R1 is in a non-working state. In the embodiment provided by the present application, the control circuit can quickly determine whether the load connected to each power output switch circuit is in a non-working state, thereby improving the control accuracy of the system.

[0040] In one embodiment, Figure 3 As shown, the switch circuit includes a field effect transistor MOS1, a second resistor R2 and a third resistor R3.

[0041] Specifically, the first end of the second resistor R2 is connected to the control circuit as the controlled end Ctrl of the switch circuit, and the second end of the second resistor R2 is respectively connected to the gate of the field effect transistor MOS1 and the first end of the third resistor R3.

[0042] Furthermore, the connection end of the second end of the third resistor R3 connected to the source of the field effect transistor MOS1 is connected to the output end of the power switching circuit as the input end of the switching circuit, and the drain of the field effect transistor MOS1 is connected to the first end of the first resistor R1.

[0043] Here, when the signal received by the controlled end Ctrl of the switch circuit is high level, because the source of the field effect tube MOS1 obtains the voltage from the backup power supply, there is no voltage drop between the source and the gate of the field effect tube MOS1, the source and the drain of the field effect tube MOS1 are disconnected, the switch circuit where the field effect tube MOS1 is located is disconnected, and the power output switch circuit where the field effect tube MOS1 is located does not output current to the load connected to it. Conversely, when the signal received by the controlled end Ctrl of the switch circuit is low level, the second resistor R2 and the third resistor R3 divide the low level signal received by the controlled end Ctrl and the voltage received from the backup power supply, there is a voltage drop between the source and the gate of the field effect tube MOS1, the source and the drain of the field effect tube MOS1 are connected, and the power output switch circuit where the field effect tube MOS1 is located outputs current to the load connected to it. The embodiment provided by the present application enables the control circuit to control the conduction or disconnection of the switch circuit by sending a high level signal or a low level signal to the controlled end of the switch circuit to control whether the load corresponding to the switch circuit is connected to the backup power supply.

[0044] In one embodiment, Figure 2 As shown, the power state monitoring circuit includes a fourth resistor R4 and a fifth resistor R5.

[0045] A first end of the fourth resistor R4 is connected to the output end of the main power supply, a second end of the fourth resistor R4 is connected to a first end of the fifth resistor R5, and a second end of the fifth resistor R5 is grounded.

[0046] Furthermore, the connection end between the fourth resistor R4 and the fifth resistor R5 leads to a backup power supply operation signal output end State, and the backup power supply operation signal output end State is connected to the control circuit to send the backup power supply operation signal to the control circuit. Here, when the main power supply is powered, the second end of the fourth resistor R4 of the power supply state monitoring circuit will generate a voltage and output a high-level signal to the control circuit. Conversely, when the main power supply stops supplying power, the second end of the fourth resistor R4 of the power supply state monitoring circuit will not generate a voltage, and a low-level signal will be output to the control circuit as a backup power supply operation signal. When the control circuit receives a low-level signal from the power supply state monitoring circuit, it can be determined that the current main power supply has stopped supplying power. The embodiment provided by the present application can determine whether the main power supply outputs electrical energy to the outside through the power supply state monitoring circuit, determine the working state of the main power supply, reduce the hardware cost of the system, and improve the operating efficiency of the system.

[0047] In one embodiment, Figure 2 As shown, the power switching circuit includes a sixth resistor R6, a first diode and a second diode.

[0048] Specifically, the anode end of the first diode is connected to the output end of the main power supply, the cathode end of the first diode is respectively connected to the input end of the power output switching circuit, the cathode end of the second diode and the first end of the sixth resistor R6, and the anode end of the second diode and the second end of the sixth resistor R6 are connected to the power output end of the backup power supply.

[0049] Furthermore, the backup power supply is an energy storage capacitor; the positive terminal of the energy storage capacitor is connected to the second access terminal of the power switching circuit, and the negative terminal of the energy storage capacitor is grounded. Specifically, the positive terminal of the energy storage capacitor can be connected to the anode terminal of the second diode and the second end of the sixth resistor R6 as the power output terminal of the backup power supply.

[0050] Here, when the main power supply is completed, the main power supply is switched to the backup power supply. Specifically, when the main power supply is powered, the current flows out from the main power supply, passes through the first diode to power the subsequent power output switch circuit, and charges the backup power supply through the first diode and the sixth resistor R6; when the main power supply is disconnected, the current flows out from the backup power supply, passes through the second diode to power the subsequent power output switch circuit. The embodiment provided by the present application enables the system to autonomously connect the main power supply or the backup power supply to the subsequent power output switch circuit based on the working state of the main power supply, so as to power the load connected to the power output switch circuit, thereby improving the power switching efficiency of the system.

[0051] In one embodiment, the control circuit includes a plurality of control subcircuits, and the control subcircuits correspond to the power output switch circuits one by one; here, each control subcircuit is connected to a specific power output switch circuit, and different control subcircuits are connected to different power output switch circuits. Further, the signal receiving end of the control subcircuit is connected to the power state monitoring circuit to receive the backup power operation signal. Specifically, the signal receiving end of each control subcircuit is connected to the backup power operation signal output end of the power state monitoring circuit to receive the backup power operation signal.

[0052] Furthermore, the first voltage receiving end of the control subcircuit is connected to the first end of the first resistor of the power output switch circuit connected to the control subcircuit, and the second voltage receiving end of the control subcircuit is connected to the second end of the first resistor to determine the voltage across the first resistor, and based on the voltage across the first resistor, determine whether the load connected to the power output switch circuit is in a non-working state.

[0053] Furthermore, the control output end of the control subcircuit is connected to the controlled end of the switch circuit of the power output switch circuit, so as to control the switch circuit to be in a disconnected state when the backup power supply operation signal is received and it is determined that the load connected to the power output switch circuit is in a non-working state.

[0054] Further, such as Figure 4 As shown, the control subcircuit includes a differential operational amplifier circuit, a latch, an inverter P and a pull-up resistor RL.

[0055] Specifically, the first access end of the differential operational amplifier circuit is connected to the first end of the first resistor of the power output switching circuit connected to the control subcircuit, the second access end of the differential operational amplifier circuit is connected to the second end of the first resistor, and the output end of the differential operational amplifier circuit is connected to the input end of the latch to send a latch signal to the latch.

[0056] Here, the differential operational amplifier circuit may include a differential operational amplifier to realize the voltage difference amplification function; when the first access terminal of the differential operational amplifier circuit receives the first voltage signal IP-1 from the first end of the first resistor, and the second access terminal of the differential operational amplifier circuit receives the second voltage signal IN-1 from the second end of the first resistor, the voltage difference between the first voltage signal IP-1 and the second voltage signal IN-1 will be calculated. If there is a voltage difference between the first voltage signal IP-1 and the second voltage signal IN-1, the voltage difference will be amplified, and a high-level signal will be output from the output terminal of the differential operational amplifier circuit. Conversely, if there is no voltage difference between the first voltage signal IP-1 and the second voltage signal IN-1 or the voltage difference is extremely small, even if the voltage difference after amplification is small, a low-level signal will be output from the output terminal of the differential operational amplifier circuit to indicate that the load is in a non-working state.

[0057] Furthermore, the output end of the differential operational amplifier circuit is connected to the input end of the latch, so as to determine that the load connected to the power output switch circuit is in a non-working state when there is no voltage difference or a very small voltage difference across the first resistor R1, and output a low-level signal to the latch as a latch signal.

[0058] Furthermore, the output end of the latch is respectively connected to the first end of the pull-up resistor RL and the input end of the inverter P, the output end of the inverter P is connected to the controlled end of the switch circuit of the power output switch circuit, and the second end of the pull-up resistor RL is connected to the external power supply Vcc.

[0059] Furthermore, the latch end LE of the latch and the enable end OE of the latch are respectively connected to the power status monitoring circuit to receive the backup power operation signal, and when the low level backup power operation signal is received, the latch signal is sent to the input end of the inverter P.

[0060] In the actual working process, when the load connected to the power output switch circuit is in a non-working state, there is no voltage difference or a very small voltage difference across the first resistor R1 in the power output switch circuit. At this time, the differential operational amplifier circuit of the control subcircuit connected to the power output switch circuit amplifies the voltage difference across the first resistor R1. Because the voltage difference is very small or does not exist, the latch signal output by the differential operational amplifier circuit to the latch is also a low-level signal. Furthermore, when the signal output by the power state monitoring circuit to the latch of the control sub-circuit is a high level, the latch is disabled, the output terminal Q of the latch is in a high impedance state, the output terminal Q is pulled to a high level by the pull-up resistor RL, and then the signal output through the inverter P is a low level, driving the switch circuit to turn on; conversely, when the signal output by the power state monitoring circuit to the latch of the control sub-circuit is a low level backup power operation signal, the latch terminal LE of the latch is a low level, and the latch saves the low level signal conditioned by the differential operational amplifier circuit into the latch as a latch signal, and at the same time, the enable terminal OE of the latch is a low level, and the low level latch signal latched inside the latch will be output through the output terminal Q, and after passing through the inverter, a high level signal is formed and sent to the controlled end of the switch circuit, controlling the switch circuit to disconnect, so as to disconnect the circuit connection between the non-working load and the backup power supply, and prevent the non-working load from consuming the power of the backup power supply.

[0061] In the embodiments provided by the present application, the control circuit can autonomously determine whether the load connected to each power output switch circuit is in a working state, and when the load is in a non-working state and the main power supply is disabled, the control circuit can autonomously disconnect the circuit between the non-working load and the backup power supply, thereby realizing automatic disconnection of the non-working load.

[0062] In one embodiment, Figure 4 As shown, the differential operational amplifier circuit includes a seventh resistor R7, an eighth resistor R8, a ninth resistor R9, a tenth resistor R10 and a differential operational amplifier Da.

[0063] Specifically, the first end of the seventh resistor R7 is connected to the first end of the first resistor R1, the second end of the seventh resistor R7 is connected to the first voltage access terminal of the differential op amp Da, the first end of the eighth resistor R8 is connected to the second end of the first resistor R1, the second end of the eighth resistor R8 is respectively connected to the second voltage access terminal of the differential op amp Da and the first end of the ninth resistor R9, and the second end of the ninth resistor R9 is grounded.

[0064] Further, the output end of the differential amplifier Da is connected to the input end of the latch as the output end of the differential amplifier circuit, and the tenth resistor R10 is connected in parallel between the first voltage access end of the differential amplifier Da and the output end of the differential amplifier Da. The embodiment provided by the present application can form a differential amplifier circuit based on the seventh resistor, the eighth resistor, the ninth resistor, the tenth resistor and the differential amplifier, thereby improving the operation stability of the differential amplifier circuit.

[0065] Here, the working process of the power management system is explained. When the main power supply is running, the second end of the fourth resistor of the power state monitoring circuit is at a high level, the enable end and the latch end of each control sub-circuit in the control circuit receive a high level, the output end of the latch is in a high impedance state, and the output end of the latch is pulled to a high level by the pull-up resistor, and then the level is reversed by the inverter and a low level is output to the controlled end of each switch circuit to drive the switch circuit to turn on. At the same time, the first diode of the power switching circuit is turned on, and the electric energy output by the main power supply can be delivered to the load through the power switching circuit and each electric energy output switch circuit.

[0066] When the main power supply stops running, the second end of the fourth resistor of the power state monitoring circuit is at a low level, and a low-level backup power supply operation signal is sent to each control sub-circuit in the control circuit. At the same time, the first diode of the power switching circuit is disconnected and the second diode is turned on, so that the backup power supply can supply power to each load.

[0067] Furthermore, when a load is in working state, a voltage difference will be generated between the two ends of the first resistor corresponding to the load due to the large current flowing through; further, the control subcircuit connected to the first resistor will transmit the voltage between the two ends of the first resistor to the differential amplifier in the control subcircuit, and the differential amplifier will amplify the voltage difference between the two ends of the first resistor. If the voltage difference is large, the differential amplifier will output a high level. Further, when the signal output by the power supply status monitoring circuit to the latch of the control subcircuit is a low-level standby power operation signal, the latch end of the latch is low-level, and the latch will store the high-level signal conditioned by the differential operational amplifier circuit into the latch as a latch signal. At the same time, the enable end of the latch is low-level, and the high-level latch signal latched in the latch will be output through the output end, and after passing through the inverter, a low-level signal will be formed, which controls the switch circuit corresponding to the above-mentioned first resistor to be turned on, and continue to supply power to the load in working state.

[0068] In contrast, when a load is in a non-working state, no current will flow through the first resistor corresponding to the load, or only a very small current will flow through, resulting in a negligible voltage difference across the first resistor; further, the control subcircuit connected to the first resistor will transmit the voltage across the first resistor to the differential amplifier in the control subcircuit, and the differential amplifier will amplify the voltage difference across the first resistor. If the voltage difference is small or zero, the differential amplifier will output a low level. Further, when the signal output by the power supply status monitoring circuit to the latch of the control subcircuit is a low-level backup power operation signal, the latch end of the latch is a low level, and the latch will store the low-level signal conditioned by the differential operational amplifier circuit into the latch as a latch signal. At the same time, the enable end of the latch is a low level, and the latch signal latched in the latch will be output through the output end, and after passing through the inverter, a high-level signal will be formed, and the switch circuit corresponding to the above-mentioned first resistor will be controlled to be disconnected, and the load in the non-working state will stop being powered.

[0069] On the other hand, an embodiment of the utility model provides an energy storage device, including a power management system as described above. The energy storage device may be a new energy photovoltaic and energy storage device. By applying the power management system described above to the energy storage device, it is possible to ensure continuous monitoring and control of the operation process of the energy storage device, thereby improving the operational stability of the energy storage device.

[0070] The above-mentioned embodiments only express several implementation methods of the utility model, and the description is relatively specific and detailed, but it cannot be understood as limiting the scope of the utility model patent. It should be pointed out that for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the utility model, which all belong to the protection scope of the utility model. Therefore, the protection scope of the utility model patent shall be based on the attached claims.

Claims

1. A power management system, arranged between a main power source and at least one load, characterized in that: The power management system includes a power status monitoring circuit, a backup power supply, a power switching circuit, a control circuit and at least one power output switch circuit, wherein: The power supply status monitoring circuit is connected to the main power supply and is used to output a backup power supply operation signal to the control circuit when it is detected that the main power supply does not output power; The first access end of the power switching circuit is connected to the main power supply, the second access end of the power switching circuit is connected to the backup power supply, and the output end of the power switching circuit is connected to the input end of each of the power output switch circuits, so as to connect the backup power supply to each of the power output switch circuits when the main power supply does not output power; The output end of the power output switch circuit is connected to the load in a one-to-one correspondence, and the controlled end of the power output switch circuit is connected to the control circuit, and is used to control the power output switch circuit to be in an on state or an off state; The control circuit is used to determine whether the load connected to each of the power output switch circuits is in a non-working state when receiving the backup power supply operation signal, and control the power output switch circuit connected to the non-working load to be in a disconnected state.

2. The power management system according to claim 1, characterized in that: The electric energy output switch circuit comprises a switch circuit and a first resistor; The input end of the switch circuit is connected to the output end of the power switching circuit, the output end of the switch circuit is connected to the first end of the first resistor, and the controlled end of the switch circuit is connected to the control circuit to be controlled to be in an on state or an off state; The second end of the first resistor is connected to the power access end of the load, and the first end of the first resistor and the second end of the first resistor are also respectively connected to the control circuit, so that the control circuit determines whether the load is in a working state based on the voltage value across the first resistor.

3. The power management system according to claim 2, characterized in that: The switch circuit includes a field effect transistor, a second resistor and a third resistor; The first end of the second resistor is connected to the control circuit as the controlled end of the switch circuit, and the second end of the second resistor is respectively connected to the gate of the field effect transistor and the first end of the third resistor; The connection end after the second end of the third resistor is connected to the source of the field effect tube is connected to the output end of the power switching circuit as the input end of the switch circuit, and the drain of the field effect tube is connected to the first end of the first resistor.

4. The power management system according to claim 1, characterized in that: The power state monitoring circuit includes a fourth resistor and a fifth resistor; The first end of the fourth resistor is connected to the output end of the main power supply, the second end of the fourth resistor is connected to the first end of the fifth resistor, and the second end of the fifth resistor is grounded: The connection end between the fourth resistor and the fifth resistor is connected to the control circuit and is used to send the backup power supply operation signal to the control circuit.

5. The power management system according to claim 1, characterized in that: The power switching circuit includes a sixth resistor, a first diode and a second diode; The anode end of the first diode is connected to the output end of the main power supply, the cathode end of the first diode is respectively connected to the input end of the power output switching circuit, the cathode end of the second diode and the first end of the sixth resistor, and the anode end of the second diode and the second end of the sixth resistor are connected to the power output end of the backup power supply.

6. The power management system according to claim 1, characterized in that: The backup power supply is an energy storage capacitor; The positive terminal of the energy storage capacitor is connected to the second access terminal of the power switching circuit, and the negative terminal of the energy storage capacitor is grounded.

7. The power management system according to claim 2, characterized in that: The control circuit includes a plurality of control subcircuits, and the control subcircuits correspond one to one with the power output switch circuits; The signal receiving end of the control subcircuit is connected to the power state monitoring circuit for receiving the backup power operation signal; The first voltage receiving end of the control subcircuit is connected to the first end of the first resistor of the power output switch circuit connected to the control subcircuit, and the second voltage receiving end of the control subcircuit is connected to the second end of the first resistor, for determining whether the load connected to the power output switch circuit is in a non-working state based on the voltage across the first resistor; The control output end of the control subcircuit is connected to the controlled end of the switch circuit of the power output switch circuit, and is used to control the switch circuit to be in a disconnected state when the backup power supply operation signal is received and it is determined that the load connected to the power output switch circuit is in a non-working state.

8. The power management system according to claim 7, characterized in that: The control subcircuit includes a differential operational amplifier circuit, a latch, an inverter and a pull-up resistor; The first access terminal of the differential operational amplifier circuit is connected to the first end of the first resistor of the power output switch circuit connected to the control subcircuit, the second access terminal of the differential operational amplifier circuit is connected to the second end of the first resistor, and the output terminal of the differential operational amplifier circuit is connected to the input terminal of the latch, so as to send a latch signal to the latch; The output end of the latch is connected to the first end of the pull-up resistor and the input end of the inverter respectively, the output end of the inverter is connected to the controlled end of the switch circuit of the power output switch circuit, and the second end of the pull-up resistor is connected to an external power supply; The latch end of the latch and the enable end of the latch are respectively connected to the power status monitoring circuit for receiving the backup power operation signal, and when receiving the backup power operation signal of a low level, the latch signal is sent to the input end of the inverter.

9. The power management system according to claim 8, characterized in that: The differential operational amplifier circuit comprises a seventh resistor, an eighth resistor, a ninth resistor, a tenth resistor and a differential operational amplifier; The first end of the seventh resistor is connected to the first end of the first resistor, the second end of the seventh resistor is connected to the first voltage access terminal of the differential amplifier, the first end of the eighth resistor is connected to the second end of the first resistor, the second end of the eighth resistor is respectively connected to the second voltage access terminal of the differential amplifier and the first end of the ninth resistor, and the second end of the ninth resistor is grounded; The output end of the differential operational amplifier is connected to the input end of the latch as the output end of the differential operational amplifier circuit, and the tenth resistor is connected in parallel between the first voltage access end of the differential operational amplifier and the output end of the differential operational amplifier.

10. An energy storage device, characterized in that: The invention comprises a power management system as claimed in any one of claims 1 to 9.

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