Power supply control circuit, energy storage cabinet and energy storage system

Abstract

The utility model relates to the technical field of power electronics, and discloses a power supply control circuit, an energy storage cabinet and an energy storage system, which are used for setting the standby power time of a battery in the switching process of a direct-current power supply and an alternating-current power supply and preventing the battery from being lack of power. Comprising an AC / DC module, a DC / DC module and at least one relay. The positive pole output end of the DC / DC module is connected with the positive pole output end of the AC / DC module and the positive pole of the load through the contact of at least one relay; the cathode output end of the DC / DC module is connected with the cathode output end of the AC / DC module and the cathode of the load; the DC / DC module is provided with a direct current input end, the direct current input end is used for being connected with a battery, and the DC / DC module is used for adjusting direct current output by the battery into direct current of target working voltage; the AC / DC module is provided with an alternating current input end, the alternating current input end is used for being connected with alternating current commercial power, and the AC / DC module is used for converting the alternating current commercial power into direct current of target working voltage.

Description

Technical Field

[0001] The utility model relates to the technical field of power electronics, and in particular to a power supply control circuit, an energy storage cabinet and an energy storage system. Background Art

[0002] With the development of new energy, energy storage systems have been widely used. Energy storage systems have diversified application scenarios, including peak-valley arbitrage, demand management, transformer expansion and other working modes. As an important part of the energy storage system, the energy storage cabinet also needs to ensure the power supply of the control system in the energy storage system. The DC loads in the control system mainly include fire detectors, water immersion sensors, energy management systems (EMS), battery management systems (BMS), etc. Most of these DC loads require uninterruptible power supply.

[0003] The traditional solution uses a dual power switching mode to provide uninterrupted power supply for DC loads. However, in the dual power switching mode, since the depth of discharge (DOD) of the energy storage cabinet battery is generally set relatively high, when the AC power is lost for a long time, the energy storage cabinet battery is required to be used as a DC power supply to power the DC load for a long time, which may cause the battery in the energy storage cabinet to run out of power and reduce the battery life. Utility Model Content

[0004] The utility model provides a power supply control circuit, an energy storage cabinet and an energy storage system, which are used to set the backup time of a battery during the switching process between a direct current power supply and an alternating current power supply to prevent the battery from running out of power.

[0005] The first aspect of the utility model provides a power supply control circuit, comprising: an AC / DC module, a DC / DC module and a control module, wherein the control module comprises at least one relay; the positive output terminal of the DC / DC module is connected to the positive output terminal of the AC / DC module and the positive pole of a load through the contact of at least one relay; the negative output terminal of the DC / DC module is connected to the negative output terminal of the AC / DC module and the negative pole of the load; the control module is used to control the conduction time between the positive output terminal of the DC / DC module and the positive pole of the load through the delayed opening or closing of the corresponding contacts of each relay; the DC / DC module has a DC input terminal, which is used to be connected to a battery, and the DC / DC module is used to adjust the DC power output by the battery to the DC power of a target working voltage; the AC / DC module has an AC input terminal, which is used to be connected to an AC mains power, and the AC / DC module is used to convert the AC mains power into the DC power of the target working voltage.

[0006] In a feasible embodiment, the control module also includes a diode unit; the first input end of the diode unit is connected to the positive output end of the AC / DC module, the second input end of the diode unit is connected to the positive output end of the DC / DC module, and the output end of the diode unit is connected to the positive electrode of the load; the diode unit is used to output the voltage of the first input end or the voltage of the second input end to the positive electrode of the load.

[0007] In a feasible implementation, the control module includes a first power-off delay relay, and the contact of the first power-off delay relay is a first delayed opening contact; the two ends of the coil in the first power-off delay relay are respectively connected to the positive and negative output ends of the AC / DC module; the first end of the first delayed opening contact is connected to the positive output end of the DC / DC module, and the second end of the first delayed opening contact is connected to the second input end of the diode unit.

[0008] In a feasible implementation manner, the control module includes a first power-off delay relay and a second power-off delay relay, the contact of the first power-off delay relay is a first delayed opening contact, and the contact of the second power-off delay relay is a second delayed opening contact; the two ends of the coil in the first power-off delay relay are respectively connected to the positive and negative output ends of the AC / DC module; the first end of the second delayed opening contact is connected to the first end of the coil of the second power-off delay relay and the positive output end of the DC / DC module, and the second end of the second delayed opening contact is connected to the second input end of the diode unit; the first end of the first delayed opening contact is connected to the second end of the coil of the second power-off delay relay, and the second end of the first delayed opening contact is connected to the negative output end of the DC / DC module.

[0009] In a feasible implementation manner, the control module includes a first solid-state relay, a second solid-state relay and a first power-on delay relay, the contact of the first solid-state relay is a first normally closed contact, the contact of the second solid-state relay is a first normally open contact, and the contact of the first power-on delay relay is a first delayed disconnect contact; the two ends of the coil in the first solid-state relay are respectively connected to the positive and negative output ends of the AC / DC module; the first end of the first normally closed contact is connected to the positive output end of the DC / DC module, and the second end of the first normally closed contact is connected to the first end of the coil of the first power-on delay relay, the first end of the first delayed disconnect contact and the first end of the first normally open contact; the second end of the first normally open contact is connected to the second input end of the diode unit; the second end of the first delayed disconnect contact is connected to the first end of the coil of the second solid-state relay, and the second end of the coil of the second solid-state relay is connected to the second end of the coil of the first power-on delay relay and the negative output end of the DC / DC module.

[0010] In a feasible implementation manner, the control module includes a first intermediate relay and a first time relay, the contact of the first intermediate relay is a first normally open contact; the two ends of the coil in the first intermediate relay are respectively connected to the positive and negative output ends of the AC / DC module; the first time relay includes a first loop input end, a second loop input end, a third loop input end and a first loop output end; the first end of the first normally open contact is connected to the second loop input end and the positive output end of the DC / DC module; the second end of the first normally open contact is connected to the first loop input end; the third loop input end is connected to the negative output end of the DC / DC module, and the first loop output end is connected to the second input end of the diode unit.

[0011] In a feasible implementation manner, the control module includes a first intermediate relay and a first power-on delay relay, the contact of the first intermediate relay is a first normally closed contact, and the contact of the first power-on delay relay is a first delayed-off break contact; the two ends of the coil in the first intermediate relay are respectively connected to the positive and negative output ends of the AC / DC module; the first end of the first normally closed contact is connected to the positive output end of the DC / DC module, and the second end of the first normally closed contact is connected to the first end of the coil of the first power-on delay relay and the first end of the first delayed-off break contact; the second end of the first delayed-off break contact is connected to the second input end of the diode unit; the second end of the coil of the first power-on delay relay is connected to the negative output end of the DC / DC module.

[0012] In a feasible implementation, the control module further includes an energy storage capacitor, which is disposed between the positive electrode of the load and the negative electrode of the load, and is used to supply power to the load during the switching delay period between the AC / DC module and the DC / DC module.

[0013] In a feasible implementation, the control module includes a battery management system BMS, a first intermediate relay and a second intermediate relay, the contact of the first intermediate relay is a first normally open contact, and the contact of the second intermediate relay is a first normally closed contact; the two ends of the coil of the first intermediate relay are respectively connected to the positive and negative output ends of the AC / DC module; the two ends of the first normally open contact are connected to the digital input end of the BMS; the coil of the second intermediate relay is connected to the high-side digital output end of the BMS, and the output voltage of the high-side output end is the power supply voltage of the BMS; the first end of the first normally closed contact is connected to the positive output end of the DC / DC module, and the second end of the first normally closed contact is connected to the second input end of the diode unit.

[0014] In a feasible implementation, the control module includes a battery management system BMS, a DC circuit breaker and a first intermediate relay, the contact of the first intermediate relay is a first normally open contact; the two ends of the coil of the first intermediate relay are respectively connected to the positive and negative output ends of the AC / DC module; the two ends of the first normally open contact are connected to the digital input end of the BMS; the positive output end of the DC / DC module is connected to the second input end of the diode unit after passing through the DC circuit breaker, and the negative output end of the DC / DC module is connected to the negative pole of the load after passing through the DC circuit breaker.

[0015] In a feasible implementation, the DC / DC module includes a working voltage protection unit, which is used to stop outputting direct current when the output voltage of the DC / DC module is less than a voltage threshold, and the voltage threshold is greater than the undervoltage protection value of the energy storage cabinet battery.

[0016] In a feasible implementation manner, a self-locking button is provided on the loop where the positive output terminal of the DC / DC module is located, and the self-locking button is used to provide a black start function and an emergency shutdown function.

[0017] A second aspect of the present invention provides an energy storage cabinet, comprising a power control circuit and a battery in any one of the embodiments of the first aspect.

[0018] A third aspect of the present invention provides an energy storage system, comprising the energy storage cabinet and an energy management system in the second aspect, wherein the energy management system is used to perform energy management on batteries in each energy storage cabinet.

[0019] In the technical solution provided by the utility model, there are an AC / DC module, a DC / DC module and a control module, wherein the control module includes at least one relay; the positive output terminal of the DC / DC module is connected to the positive output terminal of the AC / DC module and the positive pole of the load through the contact of at least one relay; the negative output terminal of the DC / DC module is connected to the negative output terminal of the AC / DC module and the negative pole of the load; the control module electrical appliance is used to control the conduction time between the positive output terminal of the DC / DC module and the positive pole of the load through the delayed disconnection or closing of the corresponding contacts of each relay; the DC / DC module has a DC input terminal, which is used to connect to the battery, and the DC / DC module is used to adjust the DC power output by the battery to the DC power of the target working voltage; the AC / DC module has an AC input terminal, which is used to connect to the AC mains, and the AC / DC module is used to convert the AC mains into the DC power of the target working voltage. In the utility model, the battery backup time is set by delaying the disconnection or closing of the relay contacts during the switching process between the DC power supply and the AC power supply, and the battery is controlled to supply power to the load for a long time to prevent the battery from being depleted. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1A schematic diagram of a power supply control circuit in an embodiment of the utility model;

[0021] Figure 2 Another schematic diagram of the power control circuit in the embodiment of the utility model;

[0022] Figure 3 A schematic diagram of the structure of a power supply control circuit in an embodiment of the utility model;

[0023] Figure 4 Another structural schematic diagram of the power supply control circuit in the embodiment of the utility model;

[0024] Figure 5 Another structural schematic diagram of the power supply control circuit in the embodiment of the utility model;

[0025] Figure 6 Another structural schematic diagram of the power supply control circuit in the embodiment of the utility model;

[0026] Figure 7 Another structural schematic diagram of the power supply control circuit in the embodiment of the utility model;

[0027] Figure 8 Another structural schematic diagram of the power supply control circuit in the embodiment of the utility model;

[0028] Fig. 9 This is another structural schematic diagram of the power control circuit in the embodiment of the utility model. DETAILED DESCRIPTION

[0029] The utility model provides a power supply control circuit, an energy storage cabinet and an energy storage system, which are used to set the backup time of a battery during the switching process between a direct current power supply and an alternating current power supply to prevent the battery from running out of power.

[0030] The terms "first", "second", "third", "fourth", etc. (if any) in the specification and claims of the present utility model and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the utility model described here, for example, can be implemented in an order other than those illustrated or described here. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0031] like Figure 1As shown, the embodiment of the utility model provides a power supply control circuit, which specifically includes:

[0032] AC / DC module 110, DC / DC module 120 and control module 130, control module 130 includes at least one relay;

[0033] The positive output terminal of the DC / DC module 120 is connected to the positive output terminal of the AC / DC module 110 and the positive electrode of the load through the contact of at least one relay;

[0034] The negative output terminal of the DC / DC module 120 is connected to the negative output terminal of the AC / DC module 110 and the negative electrode of the load;

[0035] The control module 130 is used to control the conduction time between the positive output terminal of the DC / DC module 120 and the positive electrode of the load by delaying the opening or closing of the corresponding contacts of each relay;

[0036] The DC / DC module 120 has a DC input terminal, which is used to connect to a battery. The DC / DC module 120 is used to adjust the DC power output by the battery to a DC power of a target working voltage;

[0037] The AC / DC module 110 has an AC input terminal, which is used to connect to the AC mains. The AC / DC module 110 is used to convert the AC mains into DC power of a target working voltage.

[0038] In the utility model, the battery connected to the DC input terminal and the AC mains connected to the AC input terminal are switched by delaying the disconnection or closing of the relay contacts to set the battery backup time, control the time the battery supplies power to the load, and prevent the battery from running out of power.

[0039] It should be noted that the AC input terminal of the AC / DC module 110 is connected to the AC mains, and the positive and negative electrodes of the DC input terminal of the DC / DC module 120 are respectively connected to the positive and negative electrodes of the battery. The battery connected to the DC input terminal can be arranged inside the energy storage cabinet or outside the energy storage cabinet. For multiple energy storage cabinets, some batteries can be arranged inside the energy storage cabinet and some batteries can be arranged outside the energy storage cabinet at the same time. This application does not limit this. For ease of understanding, this embodiment and subsequent embodiments are described by taking the battery arranged inside the energy storage cabinet as an example.

[0040] It is understandable that at least one relay can select a relay model with a delay function or control the signal sending time through the battery management system BMS to achieve the delay function, thereby controlling the power supply time provided by the DC / DC module to the load, avoiding the power supply battery from running out of power and affecting the battery life.

[0041] In a possible implementation, Figure 2 As shown, the control module also includes a diode unit;

[0042] The first input end of the diode unit is connected to the positive output end of the AC / DC module, the second input end of the diode unit is connected to the positive output end of the DC / DC module, and the output end of the diode unit is connected to the positive electrode of the load;

[0043] The diode unit is used to output the voltage of the first input terminal or the voltage of the second input terminal to the positive electrode of the load.

[0044] In a possible implementation, Figure 3 As shown, the control module includes a first power-off delay relay KT1, and the contact of the first power-off delay relay is a first delayed opening and closing contact KT1-1;

[0045] The two ends of the coil in the first power-off delay relay KT1 are respectively connected to the positive and negative output terminals of the AC / DC module;

[0046] A first end of the first delayed opening make contact KT1 - 1 is connected to the positive output end of the DC / DC module, and a second end of the first delayed opening make contact KT1 - 1 is connected to the second input end of the diode unit DK.

[0047] The positive output terminals of the AC / DC module 110 and the DC / DC module 120 are simultaneously connected to the two input terminals of the diode unit. The specific structure of the diode unit is as follows: Figure 3 As shown, it is composed of two diodes, forming two power supply circuits, one circuit is: first input terminal V1-first diode VD1-output terminal V0, and the other circuit is: second input terminal V2-second diode VD2-output terminal V0. The circuit corresponding to which input terminal has a larger voltage is turned on.

[0048] For example, Figure 3As shown, the AC mains is used as an AC power source to input the AC / DC module SP1, and the battery of the energy storage cabinet is used as a DC power source to input the DC / DC module SP2. The input end of the AC / DC module SP1 is energized, and the output end of the AC / DC module SP1 outputs a target working voltage. Under the action of the target working voltage, the coil of the first power-off delay relay KT1 connected to the output end of the AC / DC module SP1 is energized, and the first delayed disconnecting make contact KT1-1 corresponding to the first power-off delay relay KT1 is closed, so that the power sources of the AC / DC module SP1 and the DC / DC module SP2 are connected to the diode unit DK at the same time. Since the output voltage of the AC / DC module SP1 is adjusted to be greater than the output voltage of the DC / DC module SP2, the loop from the first input end V1 to the output end V0 in the diode unit DK is turned on, and the DC load is supplied by the AC mains. When the AC mains loses power, the coil of the first power-off delay relay KT1 loses power, and the first delayed disconnection contact KT1-1 corresponding to KT1 is delayed to disconnect. The delay time corresponding to the contact can be set according to actual needs, and it is automatically disconnected after reaching the preset timing time, so as to control the battery backup time and prevent the battery from running out of power. If the AC mains is restored during the power supply delay process of the DC / DC module SP2 (i.e., the DC / DC module is powered and the preset timing time has not been reached), then after the AC / DC module SP1 provides voltage to the coil of the first power-off delay relay KT1, the coil of the first power-off delay relay KT1 is energized, and the first delayed disconnection contact KT1-1 of KT1 remains closed. At this time, the voltage output by the AC / DC module SP1 is higher than the voltage output by the DC / DC module SP2, and the load is switched to the AC mains. When the AC power fails next time, the first power-off delay relay KT1 will be re-timed and delayed to disconnect, and this cycle will be repeated automatically.

[0049] The function of the diode unit DK is to isolate the main power output of the AC / DC module from the backup power output of the DC / DC module to prevent the two power supplies from being connected in parallel, thereby avoiding repeated actions of the first power-off delay relay KT1. It is understandable that in this embodiment, the coil of the first power-off delay relay KT1 can also be directly connected to the LN ends of the AC mains, and only the coil operating voltage needs to be modified during selection, and the diode unit DK can be cancelled at this time.

[0050] Optionally, the DC / DC module may also include a working voltage protection unit, which is used to stop outputting direct current when the output voltage of the DC / DC module is less than a voltage threshold, and the voltage threshold is greater than an undervoltage protection value of the energy storage cabinet battery.

[0051] The working voltage protection unit sets the lower limit value (voltage threshold) of the power supply working voltage of the DC / DC module according to the capacity configuration of different batteries. The lower limit value can be slightly larger than the battery undervoltage protection value, that is, the DC / DC module stops output before the battery performs undervoltage protection, so as to prevent the battery from running out of power.

[0052] Optionally, a self-locking button is provided on the circuit where the positive output terminal of the DC / DC module is located, and the self-locking button is used to provide a black start function and an emergency shutdown function.

[0053] like Figure 3 As shown, the self-locking button SB2 is manually closed. The self-locking button SB2 is always closed under normal working conditions and is only used to disconnect or close the output circuit of the DC / DC module, control the disconnection and conduction of the output circuit of the DC / DC module, perform emergency control or maintenance, or perform a black start of part of the circuit.

[0054] It should be noted that if the capacity of a single contact of the relay does not meet the load current requirements, it can be expanded by connecting multiple contacts in parallel to meet the requirements, such as Figure 3 As shown in the figure, the number of the first delayed opening and closing contacts KT1-1 of KT1 is two, and it can also be drawn as one or more than two in parallel. The contacts drawn in the accompanying drawings do not represent a limit on the number of contacts, and can be selected according to actual needs, and there is no limit on the specific number.

[0055] It is understandable that the AC / DC module and the DC / DC module also need to be grounded, such as Figure 3 The AC / DC module and the DC / DC module shown are also connected to a PE line. In this embodiment and subsequent embodiments, the AC / DC module and the DC / DC module need to be grounded, which will not be described separately.

[0056] In a possible implementation, Figure 4 As shown, the control module includes a first power-off delay relay KT1 and a second power-off delay relay KT2, the contact of the first power-off delay relay KT1 is a first delayed opening and closing contact KT1-1, and the contact of the second power-off delay relay KT2 is a second delayed opening and closing contact KT2-1;

[0057] The two ends of the coil in the first power-off delay relay KT1 are respectively connected to the positive and negative output terminals of the AC / DC module;

[0058] The first end of the second delayed disconnecting make contact KT2-1 is connected to the first end of the coil of the second power-off delay relay KT2 and the positive output end of the DC / DC module, and the second end of the second delayed disconnecting make contact KT2-1 is connected to the second input end of the diode unit DK;

[0059] The first end of the first delayed opening make contact KT1-1 is connected to the second end of the coil of the second power-off delay relay KT2, and the second end of the first delayed opening make contact KT1-1 is connected to the negative output end of the DC / DC module.

[0060] The positive output terminals of the AC / DC module and the DC / DC module are simultaneously connected to the two input terminals of the diode unit DK. The specific structure of the diode unit is as follows: Figure 4 As shown, it is composed of two diodes, forming two power supply circuits, one circuit is: first input terminal V1-first diode VD1-output terminal V0, and the other circuit is: second input terminal V2-second diode VD2-output terminal V0. The circuit corresponding to which input terminal has a larger voltage is turned on.

[0061] For example, Figure 4As shown, the AC mains is used as an AC power source to input the AC / DC module SP1, and the battery of the energy storage cabinet is used as a DC power source to input the DC / DC module SP2. The input end of the AC / DC module SP1 is energized, and the output end of the AC / DC module SP1 outputs a target working voltage. Under the action of the target working voltage, the coil of the first power-off delay relay KT1 connected to the output end of the AC / DC module SP1 is energized, and the first delayed disconnecting make contact KT1-1 corresponding to the first power-off delay relay KT1 is closed, so that the coil of the second power-off delay relay KT2 is energized, and the second delayed disconnecting make contact KT2-1 is closed. The power sources of the AC / DC module SP1 and the DC / DC module SP2 are simultaneously connected to the diode unit DK. Since the output voltage of the AC / DC module SP1 is adjusted to be greater than the output voltage of the DC / DC module SP2, the loop from the first input end V1 to the output end V0 in the diode unit DK is turned on, and the DC load is supplied by the AC mains. When the AC mains power is lost, the coil of the first power-off delay relay KT1 loses power, and the first delayed disconnecting contact KT1-1 corresponding to KT1 is delayed to disconnect. The delay time of the first delayed disconnecting contact KT1-1 and the second delayed disconnecting contact KT2-1 can be set according to actual needs. They will automatically disconnect after reaching the preset timing time, thereby controlling the battery backup time and preventing the battery from running out of power. If the AC mains is restored during the power supply delay process of the DC / DC module SP2 (i.e., the DC / DC module is powered and the preset timing duration has not been reached), then after the AC / DC module SP1 provides voltage to the coil of the first power-off delay relay KT1, the coil of the first power-off delay relay KT1 is energized, the first delayed disconnection contact KT1-1 of KT1 remains closed, the coil of the second power-off delay relay KT2 is always energized, and the second delayed disconnection contact KT2-1 of KT2 remains closed. At this time, the voltage output by the AC / DC module SP1 is higher than the voltage output by the DC / DC module SP2, and the load is switched to AC mains power supply. When the AC power fails next time, the first power-off delay relay KT1 and the second power-off delay relay KT2 restart the timing delay disconnection, and this cycle repeats automatically.

[0062] The function of the diode unit DK is to isolate the main power output of the AC / DC module from the backup power output of the DC / DC module to prevent the two power supplies from being connected in parallel, thereby avoiding repeated action of the first power-off delay relay KT1. It is understandable that in this embodiment, the coil of the first power-off delay relay KT1 can also be directly connected to the LN ends of the AC mains, and only the coil working voltage needs to be modified during selection. In addition, since there is no relay coil at the output end of the AC / DC module, the diode unit DK can be cancelled at this time.

[0063] Optionally, the DC / DC module may also include a working voltage protection unit, which is used to stop outputting direct current when the output voltage of the DC / DC module is less than a voltage threshold, and the voltage threshold is greater than an undervoltage protection value of the energy storage cabinet battery.

[0064] The working voltage protection unit sets the lower limit value (voltage threshold) of the power supply working voltage of the DC / DC module according to the capacity configuration of different batteries. The lower limit value can be slightly larger than the battery undervoltage protection value, that is, the DC / DC module stops output before the battery performs undervoltage protection, so as to prevent the battery from running out of power.

[0065] Optionally, a self-locking button is provided on the circuit where the positive output terminal of the DC / DC module is located, and the self-locking button is used to provide a black start function and an emergency shutdown function.

[0066] like Figure 4 As shown, the self-locking button SB2 is always closed under normal working conditions and is only used to disconnect or close the output circuit of the DC / DC module, control the disconnection and conduction of the output circuit of the DC / DC module, perform emergency control or maintenance, or perform a black start of a part of the circuit.

[0067] It should be noted that if the capacity of a single contact of the relay does not meet the load current requirements, it can be expanded by connecting multiple contacts in parallel to meet the requirements, such as Figure 4 As shown in the figure, the number of the first delayed opening and closing contacts KT1-1 of KT1 is one, and it can also be drawn as two or more in parallel, and the number of the second delayed opening and closing contacts KT2-1 of KT2 is two, and it can also be drawn as one or more. The contacts shown in the accompanying drawings do not represent a limitation on the number of contacts, but are only a schematic diagram of the positions of the contacts, which can be selected according to actual needs, and the specific number is not limited.

[0068] In a possible implementation, Figure 5 As shown, the control module includes a first solid-state relay KM1, a second solid-state relay KM2 and a first power-on delay relay KT1, the contact of the first solid-state relay KM1 is a first normally closed contact, the contact of the second solid-state relay KM2 is a first normally open contact, and the contact of the first power-on delay relay KT1 is a first delayed opening break contact KT1-2;

[0069] The two ends of the coil in the first solid-state relay are respectively connected to the positive and negative output terminals of the AC / DC module;

[0070] The first end of the first normally closed contact is connected to the positive output end of the DC / DC module, and the second end of the first normally closed contact is connected to the first end of the coil of the first power-on delay relay KT1, the first end of the first delayed disconnection break contact KT1-2 and the first end of the first normally open contact;

[0071] The second end of the first normally open contact is connected to the second input end of the diode unit DK;

[0072] The second end of the first delayed opening break contact KT1-2 is connected to the first end of the coil of the second solid-state relay KM2, and the second end of the coil of the second solid-state relay KM2 is connected to the second end of the coil of the first power-on delay relay KT1 and the negative output end of the DC / DC module.

[0073] For example, Figure 5 As shown, the AC mains is used as an AC power source to input into the AC / DC module SP1, and the battery of the energy storage cabinet is used as a DC power source to input into the DC / DC module SP2. The input end of the AC / DC module SP1 is energized, and the output end of the AC / DC module SP1 outputs a target working voltage. Under the action of the target working voltage, the coil of the first solid-state relay KM1 connected to the output end of the AC / DC module SP1 is energized, and the first normally closed contact corresponding to the first solid-state relay KM1 is disconnected. The DC / DC module SP2 has no output voltage, and the DC load is supplied by the AC mains. When the AC mains power is lost, the coil of KM1 loses power, and the first normally closed contact corresponding to the first solid-state relay KM1 closes. At this time, the coil of the first power-on delay relay KT1 is energized, and the first delayed disconnection contact KT1-2 of KT1 is delayed to disconnect, and the coil of the second solid-state relay KM2 is energized, and the first normally open contact of KM2 is closed. The DC / DC module outputs voltage to the positive pole of the load. After the first power-on delay relay KT1 reaches the preset timing length, its corresponding first delayed disconnection contact KT1-2 is automatically disconnected, and the KM2 coil of the second solid-state relay loses power. The first normally open contact corresponding to the second solid-state relay KM2 is disconnected, controlling the backup time of the battery in the energy storage cabinet to prevent the battery from running out of power. Among them, the delay time of the first delayed disconnection contact KT1-2 can be set according to demand and is not limited here. If the AC mains power is restored during the power supply delay process of the DC / DC module SP2 (i.e., the DC / DC module is powered and the preset timing duration has not been reached), then after the AC / DC module SP1 provides voltage to the coil of the first solid-state relay KM1, the coil of the first solid-state relay KM1 is energized, the first normally closed contact corresponding to the first solid-state relay KM1 is disconnected, the DC / DC module SP2 stops outputting voltage, and the AC mains power of the AC / DC module SP1 is used to power the load. When the AC power supply fails next time, the first power-on delay relay KT1 will restart the timing delay and disconnect, and the cycle will repeat automatically.

[0074] The function of the diode unit DK is to isolate the main power output of the AC / DC module SP1 from the backup power output of the DC / DC module SP2 to prevent the two power supplies from being connected in parallel, thereby avoiding repeated action of the first solid-state relay KM1.

[0075] It is understandable that in this embodiment, the coil of the first solid-state relay KM1 can also be directly connected to the LN ends of the AC mains, and only the coil operating voltage needs to be modified during selection. In addition, because there is no relay coil at the output end of the AC / DC module SP1, the diode unit DK can be cancelled at this time.

[0076] Optionally, the DC / DC module may also include a working voltage protection unit, which is used to stop outputting direct current when the output voltage of the DC / DC module is less than a voltage threshold, and the voltage threshold is greater than an undervoltage protection value of the energy storage cabinet battery.

[0077] The working voltage protection unit sets the lower limit value (voltage threshold) of the power supply working voltage of the DC / DC module according to the capacity configuration of different batteries. The lower limit value can be slightly larger than the battery undervoltage protection value, that is, the DC / DC module stops output before the battery performs undervoltage protection, so as to prevent the battery from running out of power.

[0078] Optionally, a self-locking button is provided on the circuit where the positive output terminal of the DC / DC module is located, and the self-locking button is used to provide a black start function and an emergency shutdown function.

[0079] like Figure 5 As shown, the self-locking button SB2 is always closed under normal working conditions and is only used to disconnect or close the output circuit of the DC / DC module, control the disconnection and conduction of the output circuit of the DC / DC module, perform emergency control or maintenance, or perform a black start of a part of the circuit.

[0080] It should be noted that if the capacity of a single contact of the relay does not meet the load current requirements, it can be expanded by connecting multiple contacts in parallel to meet the requirements, such as Figure 5 As shown in the figure, the number of the first normally closed contacts of KM1 is one, and it can also be drawn as two or more in parallel; the number of the first normally open contacts of KM2 is one, and it can also be drawn as two or more in parallel; the number of the first delayed-breaking contacts KT1-2 of KT1 is one, and it can also be drawn as two or more in parallel. The contacts shown in the accompanying drawings do not represent a limitation on the number of contacts, but are only a schematic diagram of the positions of the contacts, which can be selected according to actual needs, and the specific number is not limited.

[0081] In a possible implementation, Figure 6 As shown, the control module includes a first intermediate relay KM1 and a first time relay KT1, and the contact of the first intermediate relay is a first normally open contact;

[0082] The two ends of the coil in the first intermediate relay KM1 are respectively connected to the positive and negative output terminals of the AC / DC module SP1;

[0083] The first time relay KT1 includes a first loop input end, a second loop input end, a third loop input end and a first loop output end;

[0084] The first end of the first normally open contact is connected to the second loop input end and the positive output end of the DC / DC module;

[0085] The second end of the first normally open contact is connected to the first circuit input end;

[0086] The third loop input end is connected to the negative output end of the DC / DC module, and the first loop output end is connected to the second input end of the diode unit.

[0087] For example, Figure 6 As shown, the AC mains is used as an AC power source to input the AC / DC module SP1, and the battery of the energy storage cabinet is used as a DC power source to input the DC / DC module SP2. The input end of the AC / DC module SP1 is energized, and the output end of the AC / DC module SP1 outputs a target working voltage. Under the action of the target working voltage, the coil of the first intermediate relay KM1 connected to the output end of the AC / DC module SP1 is energized, and the first normally open contact corresponding to the first intermediate relay KM1 is closed. The first time relay KT1 controls the circuit from the first circuit input end A to the first circuit output end B to be turned on, and the DC load is supplied by the AC mains. When the AC mains loses power, the first intermediate relay KM1 loses power, the first normally open contact corresponding to KM1 is disconnected, and the first time relay KT1 detects the disconnection signal of the first loop input terminal A. The first time relay KT1 controls the loop from the first loop input terminal A to the first loop output terminal B to be disconnected, and controls the loop from the second loop input terminal A1 to the first loop output terminal B to be connected. After reaching the preset timing time, the loop from the second loop input terminal A1 to the first loop output terminal B is automatically disconnected, thereby controlling the battery backup time in the DC / DC module and preventing the battery from running out of power. If the AC mains is restored during the DC / DC power supply delay process, the first intermediate relay KM1 is energized, the first normally open contact is closed, the A to B loop of the first time relay KT1 is connected, and the A1 to B loop is disconnected. Because the output voltage of the DC / DC module SP2 is less than the output voltage of the AC / DC module SP1, the load is switched to AC mains power supply. When the AC power fails next time, the above process is repeated, and the cycle is repeated automatically.

[0088] The function of the diode unit DK is to isolate the main power output of the AC / DC module SP1 from the backup power output of the DC / DC module to prevent the two power supplies from being connected in parallel and avoid causing repeated actions of the first intermediate relay KM1.

[0089] It is understandable that in this embodiment, the coil of the first intermediate relay KM1 can also be directly connected to the LN ends of the AC mains, and only the coil working voltage needs to be modified during selection. In addition, since there is no relay coil at the output end of the AC / DC module SP1, the diode unit DK can be cancelled. The first intermediate relay can be replaced by a solid-state relay to achieve the same function, and the details are not repeated here.

[0090] Optionally, the DC / DC module may also include a working voltage protection unit, which is used to stop outputting direct current when the output voltage of the DC / DC module is less than a voltage threshold, and the voltage threshold is greater than an undervoltage protection value of the energy storage cabinet battery.

[0091] The working voltage protection unit sets the lower limit value (voltage threshold) of the power supply working voltage of the DC / DC module according to the capacity configuration of different batteries. The lower limit value can be slightly larger than the battery undervoltage protection value, that is, the DC / DC module stops output before the battery performs undervoltage protection, so as to prevent the battery from running out of power.

[0092] Optionally, a self-locking button is provided on the circuit where the positive output terminal of the DC / DC module is located, and the self-locking button is used to provide a black start function and an emergency shutdown function.

[0093] like Figure 6 As shown, the self-locking button SB2 is always closed under normal working conditions and is only used to disconnect or close the output circuit of the DC / DC module, control the disconnection and conduction of the output circuit of the DC / DC module, perform emergency control or maintenance, or perform a black start of a part of the circuit.

[0094] It should be noted that if the capacity of a single contact of the relay does not meet the load current requirements, it can be expanded by connecting multiple contacts in parallel to meet the requirements, such as Figure 6 As shown in the figure, the number of the first normally open contacts of KM1 is two, and it can also be drawn as one or more than two in parallel. The contacts shown in the accompanying drawings do not represent a limit on the number of contacts, but are only a schematic diagram of the positions of the contacts, which can be selected according to actual needs, and the specific number is not limited.

[0095] In a possible implementation, Figure 7 As shown, the control module includes a first intermediate relay KM1 and a first power-on delay relay KT1, the contact of the first intermediate relay KM1 is a first normally closed contact, and the contact of the first power-on delay relay KT1 is a first delayed opening break contact KT1-2;

[0096] The two ends of the coil in the first intermediate relay KM1 are respectively connected to the positive and negative output terminals of the AC / DC module SP1;

[0097] The first end of the first normally closed contact is connected to the positive output end of the DC / DC module, and the second end of the first normally closed contact is connected to the first end of the coil of the first power-on delay relay KT1 and the first end of the first delayed opening break contact KT1-2;

[0098] The second end of the first delayed breaking contact KT1-2 is connected to the second input end of the diode unit DK;

[0099] The second end of the coil of the first power-on delay relay KT1 is connected to the negative output terminal of the DC / DC module.

[0100] For example, Figure 7 As shown, the AC mains is used as an AC power source to input the AC / DC module SP1, and the battery of the energy storage cabinet is used as a DC power source to input the DC / DC module SP2. The input end of the AC / DC module SP1 is powered, and the output end of the AC / DC module SP1 outputs the target working voltage. Under the action of the target working voltage, the coil of the first intermediate relay KM1 connected to the output end of the AC / DC module SP1 is powered, and the first normally closed contact corresponding to the first intermediate relay KM1 is disconnected, the output of the DC / DC module SP2 is interrupted, the first power-on delay relay KT1 is powered off, and the timing is not started. The first delayed disconnection break contact KT1-2 is normally closed. When the AC mains is powered off, the first intermediate relay KM1 is also powered off, the first normally closed contact is closed, the first power-on delay relay KT1 is powered on, and the timing starts. After the timing reaches the preset timing time, the first delayed disconnection break contact KT1-2 is disconnected, and the DC / DC module SP2 stops supplying power to the DC load, which limits the battery backup time and prevents the battery from running out of power. If the AC mains is restored during the timing of the first power-on delay relay KT1, the coil of the first intermediate relay KM1 is energized, the first normally closed contact is disconnected, the first power-on delay relay KT1 loses power, and the timing stops. At this time, the AC / DC module SP1 supplies power to the load. After the first power-on delay relay KT1 loses power, the first delayed disconnecting moving contact KT1-2 is normally closed. When the AC power fails next time, the above process is repeated, and this cycle is repeated automatically.

[0101] In a feasible implementation, the control module further includes an energy storage capacitor, which is disposed between the positive electrode and the negative electrode of the load and is used to supply power to the load during the switching delay period of the AC / DC module SP1 and the DC / DC module SP2.

[0102] like Figure 7As shown, the energy storage capacitor C is connected between the positive pole and the negative pole of the load, and supports the power supply of the DC load during the delay period when the AC / DC module SP1 and the DC / DC module SP2 perform power switching, so as to avoid the load from powering off and restarting. It should be noted that because the intermediate relay is a mechanical structure, the relay action time takes tens of milliseconds. When the power-off delay output time is less than the relay action time, it will cause the load to be short-term power-off and restart. In order to avoid power-off and restart, a storage capacitor can be provided. The minimum capacity of the storage capacitor meets the requirements: C = 2 × P × t / (U1 2 -U2 2 ), where C is the capacity of the energy storage capacitor (in mF), P is the power of the DC load (in W), t is the time required for the capacitor to support (in ms); U1 is the rated voltage of the DC load for normal operation (in V), and U2 is the minimum voltage of the DC load for normal operation (in V).

[0103] The function of the diode unit DK is to isolate the main power output of the AC / DC module SP1 from the backup power output of the DC / DC module SP2 to prevent the two power supplies from being connected in parallel and avoid causing repeated actions of the first intermediate relay KM1.

[0104] It is understandable that in this embodiment, the coil of the first intermediate relay KM1 can also be directly connected to the LN ends of the AC mains, and only the coil working voltage needs to be modified during selection, and because there is no relay coil at the output end of the AC / DC module SP1, the diode unit DK can be cancelled. Among them, the first intermediate relay can be replaced by a solid-state relay to achieve the same function. When replaced by a solid-state relay, the energy storage capacitor C can be cancelled because the action time of the solid-state relay is very short.

[0105] Optionally, the DC / DC module may also include a working voltage protection unit, which is used to stop outputting direct current when the output voltage of the DC / DC module is less than a voltage threshold, and the voltage threshold is greater than an undervoltage protection value of the energy storage cabinet battery.

[0106] The working voltage protection unit sets the lower limit value (voltage threshold) of the power supply working voltage of the DC / DC module according to the capacity configuration of different batteries. The lower limit value can be slightly larger than the battery undervoltage protection value, that is, the DC / DC module stops output before the battery performs undervoltage protection, so as to prevent the battery from running out of power.

[0107] Optionally, a self-locking button is provided on the circuit where the positive output terminal of the DC / DC module is located, and the self-locking button is used to provide a black start function and an emergency shutdown function.

[0108] like Figure 7As shown, the self-locking button SB2 is always closed under normal working conditions and is only used to disconnect or close the output circuit of the DC / DC module, control the disconnection and conduction of the output circuit of the DC / DC module, perform emergency control or maintenance, or perform a black start of a part of the circuit.

[0109] It should be noted that if the capacity of a single contact of the relay does not meet the load current requirements, it can be expanded by connecting multiple contacts in parallel to meet the requirements, such as Figure 7 As shown, the number of the first normally closed contacts of KM1 in the figure is two, and it can also be drawn as one or more in parallel. The number of the first delayed-opening moving-breaking contacts KT1-2 of KT1 in the figure is two, and it can also be drawn as one or more in parallel. The contacts shown in the accompanying drawings do not represent a limit on the number of contacts, but are only a schematic diagram of the positions of the contacts, which can be selected according to actual needs, and there is no limit on the specific number.

[0110] In a possible implementation, Figure 8 As shown, the control module includes a battery management system BMS, a first intermediate relay KM1 and a second intermediate relay KM2, the contact of the first intermediate relay KM1 is a first normally open contact, and the contact of the second intermediate relay KM2 is a first normally closed contact;

[0111] The two ends of the coil of the first intermediate relay KM1 are respectively connected to the positive and negative output terminals of the AC / DC module SP1;

[0112] Both ends of the first normally open contact are connected to the digital input terminals of the BMS;

[0113] The coil of the second intermediate relay KM2 is connected to the high-side digital output terminal of the BMS, and the output voltage of the high-side output terminal is the power supply voltage of the BMS;

[0114] A first end of the first normally closed contact is connected to the positive output end of the DC / DC module, and a second end of the first normally closed contact is connected to the second input end of the diode unit.

[0115] For example, Figure 8As shown, the first normally open contact of the first intermediate relay KM1 is connected to the digital input terminal DI of the BMS, and the coil of the second intermediate relay KM2 is connected to the high-side digital output terminal DO of the BMS. The voltage when DO is output is the power supply voltage of the BMS. After the self-locking button SB2 is closed, the coil of the second intermediate relay KM2 is de-energized, the first normally closed contact of KM2 is closed, the AC mains power supply and the battery are input at the same time, the AC mains is used as the AC power supply to input the AC / DC module SP1, and the battery of the energy storage cabinet is used as the DC power supply to input the DC / DC module SP2, the input end of the AC / DC module SP1 is energized, the output end of the AC / DC module SP1 outputs the target working voltage, the coil of the first intermediate relay KM1 is energized, the first normally open contact corresponding to the first intermediate relay KM1 is closed, and the DI of the BMS collects the signal that the first normally open contact changes from the open position to the closed position. At this time, the output end DO of the BMS has no output, the first normally closed contact of KM2 is closed, the AC / DC module SP1 and the DC / DC module SP2 are connected to the diode unit DK at the same time, and because the output voltage of the AC / DC module SP1 is adjusted to be greater than the output voltage of the DC / DC module SP2, the V1-V0 circuit of the diode unit DK is turned on, and the DC load is powered by the AC mains. When the AC mains fails, the DC / DC module SP2 switches to power the DC load without delay. At the same time, the BMS detects the signal that the contact of the first intermediate relay KM1 changes from the closed position to the open position, and the BMS starts timing. After the preset time is reached, the high-side output terminal DO of the BMS outputs voltage, the second intermediate relay KM2 is energized, the first normally closed contact of KM2 is disconnected, and the DC / DC module SP2 stops supplying power to the DC load, thereby controlling the battery backup time and preventing the battery from running out of power. If the DC / DC module SP2 is supplying power, and the AC mains is restored during the timing of the BMS, the BMS detects that the contact of the first intermediate relay KM1 changes from the open position to the closed position, stops timing and resets the current timing, the high-side output terminal DO of the BMS does not output, and the first normally closed contact of KM2 is closed. At this time, the output voltage of the AC / DC module SP1 is higher than the output voltage of the DC / DC module SP2, and the load automatically switches to the mains power supply. When the AC power fails next time, the above process is repeated, and the cycle is repeated automatically. In this embodiment, the BMS is used to control the high-side digital output terminal DO to stop outputting voltage when the digital input terminal DI detects that the first normally open contact changes from the open position to the closed position; the BMS is also used to start timing when the digital input terminal DI detects that the first normally open contact changes from the closed position to the open position, and control the high-side digital output terminal DO to output voltage after a preset time period.

[0116] The function of the diode unit DK is to isolate the main power output of the AC / DC module SP1 from the backup power output of the DC / DC module SP2 to prevent the two power supplies from being connected in parallel and avoid causing repeated actions of the first intermediate relay KM1.

[0117] It is understandable that in this embodiment, the coil of the first intermediate relay KM1 can also be directly connected to the LN ends of the AC mains, and only the coil working voltage needs to be modified during selection. In addition, since there is no relay coil at the output end of the AC / DC module SP1, the diode unit DK can be cancelled. The first intermediate relay and the second intermediate relay can also be replaced by solid-state relays or other types of relays to achieve the same function, which will not be described in detail here.

[0118] It should be noted that the contact of the second intermediate relay KM2 can also be a second normally open contact. Then, when the contact of the first intermediate relay KM1 changes from open to closed, the input terminal DI of the BMS receives a signal, and the output terminal DO of the BMS outputs a DC24V voltage, so that the second normally open contact of KM2 is closed, and the power supplies of the AC / DC module SP1 and the DC / DC module SP2 are simultaneously connected to the diode unit DK. Since the output voltage of the AC / DC module SP1 is adjusted to be greater than the output voltage of the DC / DC module SP2, the V1-V0 loop in the diode unit DK is turned on, and the AC mains supplies power to the DC load. When the AC mains loses power, the DC / DC module SP2 is switched to supply power to the DC load, and there is no delay switching. At the same time, the BMS detects that the contact signal of the first intermediate relay KM1 changes from closed to open, and the BMS starts timing internally. After the preset timing duration is reached, the high-side output DO of the BMS stops outputting DC24V voltage, the coil of the second intermediate relay KM2 loses power, the second normally open contact of KM2 is disconnected, and the battery stops supplying power to the DC load, thereby controlling the battery backup time and preventing the battery from running out of power.

[0119] Optionally, the DC / DC module may also include a working voltage protection unit, which is used to stop outputting direct current when the output voltage of the DC / DC module is less than a voltage threshold, and the voltage threshold is greater than an undervoltage protection value of the energy storage cabinet battery.

[0120] The working voltage protection unit sets the lower limit value (voltage threshold) of the power supply working voltage of the DC / DC module according to the capacity configuration of different batteries. The lower limit value can be slightly larger than the battery undervoltage protection value, that is, the DC / DC module stops output before the battery performs undervoltage protection, so as to prevent the battery from running out of power.

[0121] Optionally, a self-locking button is provided on the circuit where the positive output terminal of the DC / DC module is located, and the self-locking button is used to provide a black start function and an emergency shutdown function.

[0122] like Figure 8 As shown, the self-locking button SB2 is always closed under normal working conditions and is only used to disconnect or close the output circuit of the DC / DC module, control the disconnection and conduction of the output circuit of the DC / DC module, perform emergency control or maintenance, or perform a black start of a part of the circuit.

[0123] It should be noted that if the capacity of a single contact of the relay does not meet the load current requirements, it can be expanded by connecting multiple contacts in parallel to meet the requirements, such as Figure 8 As shown in the figure, the number of the first normally closed contacts of KM2 is two, and it can also be drawn as one or more than two in parallel. The contacts shown in the accompanying drawings do not represent a limit on the number of contacts, but are only a schematic diagram of the positions of the contacts, which can be selected according to actual needs, and there is no limit on the specific number.

[0124] In a possible implementation, Fig. 9 As shown, the control module includes a battery management system BMS, a DC circuit breaker QF and a first intermediate relay KM1, and the contact of the first intermediate relay KM1 is a first normally open contact;

[0125] The two ends of the coil of the first intermediate relay KM1 are respectively connected to the positive and negative output terminals of the AC / DC module SP1;

[0126] Both ends of the first normally open contact are connected to the digital input terminals of the BMS;

[0127] The positive output terminal of the DC / DC module is connected to the second input terminal of the diode unit DK after passing through the DC circuit breaker QF, and the negative output terminal of the DC / DC module is connected to the negative pole of the load after passing through the DC circuit breaker QF;

[0128] The electrical operation of the DC circuit breaker QF is controlled by the closing signal or opening signal output by the output terminal DO of the BMS.

[0129] For example, Fig. 9As shown, the first normally open contact of the first intermediate relay KM1 is connected to the digital input terminal DI of the BMS. Press the self-locking button SB2 to manually close the DC circuit breaker QF, and the AC mains power supply and battery are input at the same time. The AC mains is used as the AC power supply to input the AC / DC module SP1, and the battery of the energy storage cabinet is used as the DC power supply to input the DC / DC module SP2. The output terminal of the AC / DC module SP1 outputs the target working voltage, the coil of the first intermediate relay KM1 is energized, and the first normally open contact corresponding to the first intermediate relay KM1 is closed. The DI signal of the BMS collects the signal that the first normally open contact changes from the open position to the closed position. At this time, the electric control of the DC circuit breaker QF is energized to prepare for the circuit breaker action. The AC / DC module SP1 and the DC / DC module SP2 are connected to the diode unit DK at the same time. Since the output voltage of the AC / DC module SP1 is adjusted to be greater than the output voltage of the DC / DC module SP2, the V1-V0 circuit of the diode unit DK is turned on, and the AC mains supplies power to the DC load. When the AC mains fails, the DC / DC module SP2 switches to supply power to the DC load without delay. At the same time, the BMS detects that the contact of the first intermediate relay KM1 changes from the closed position to the open position, and the BMS starts timing. After the preset timing duration is reached, the BMS's opening control DO output port controls the QF electric operator to open the gate, and the DC / DC module SP2 stops supplying power to the DC load, thereby controlling the battery backup time and preventing the battery from running out of power. If the DC / DC module SP2 is supplying power, and the AC mains is restored during the BMS timing, the BMS detects that the contact of the first intermediate relay KM1 changes from the open position to the closed position, stops timing and resets the current timing, and the BMS's closing control DO output port controls the QF electric operator to close the gate. At this time, the output voltage of the AC / DC module SP1 is higher than the output voltage of the DC / DC module SP2, and the load automatically switches to the mains. When the AC power fails next time, the above process is repeated, and the cycle is repeated automatically. In this embodiment, the BMS is used to stop timing and return to zero when the digital input terminal detects that the first normally open contact changes from the open position to the closed position, and controls the electrical operation of the DC circuit breaker to close. The BMS is also used to start timing when the digital input terminal detects that the first normally open contact changes from the closed position to the open position, and controls the electrical operation of the DC circuit breaker to open after a preset period of time.

[0130] The function of the diode unit DK is to isolate the main power output of the AC / DC module SP1 from the backup power output of the DC / DC module to prevent the two power supplies from being connected in parallel and avoid causing repeated actions of the first intermediate relay KM1.

[0131] It is understandable that in this embodiment, the coil of the first intermediate relay KM1 can also be directly connected to the LN ends of the AC mains, and only the coil working voltage needs to be modified during selection. In addition, since there is no relay coil at the output end of the AC / DC module SP1, the diode unit DK can be cancelled. The first intermediate relay can also be replaced by a solid-state relay or other types of relays to achieve the same function, which will not be described in detail here.

[0132] Optionally, the DC / DC module may also include a working voltage protection unit, which is used to stop outputting direct current when the output voltage of the DC / DC module is less than a voltage threshold, and the voltage threshold is greater than an undervoltage protection value of the energy storage cabinet battery.

[0133] The working voltage protection unit sets the lower limit value (voltage threshold) of the power supply working voltage of the DC / DC module according to the capacity configuration of different batteries. The lower limit value can be slightly larger than the battery undervoltage protection value, that is, the DC / DC module stops output before the battery performs undervoltage protection, so as to prevent the battery from running out of power.

[0134] Optionally, a self-locking button is provided on the circuit where the positive output terminal of the DC / DC module is located, and the self-locking button is used to provide a black start function and an emergency shutdown function.

[0135] like Fig. 9 As shown, the self-locking button SB2 is always closed under normal working conditions and is only used to disconnect or close the output circuit of the DC / DC module, control the disconnection and conduction of the output circuit of the DC / DC module, perform emergency control or maintenance, or perform a black start of a part of the circuit.

[0136] The utility model also provides an energy storage cabinet, comprising the power control circuit and the battery in any one of the above embodiments.

[0137] Among them, a single local energy storage cabinet, when the AC mains is normal, gives priority to the mains power supply, and does not use the battery power supply of the local energy storage cabinet. When the AC mains fails, it switches to the battery power supply of the local energy storage cabinet to achieve uninterrupted operation of the DC load of the local energy storage cabinet. At the same time, the battery backup time of the local energy storage cabinet can be set to avoid long-term backup power causing the battery of the local energy storage cabinet to run out of power, affecting the battery life.

[0138] It should be noted that the utility model solves the problem of battery depletion that may be caused by using a single energy storage cabinet battery as a backup power source, and can not only meet the uninterrupted switching of the DC power supply and the AC power supply of a single energy storage cabinet, but also set the backup power time of the battery of a single energy storage cabinet to prevent the battery of the energy storage cabinet from depleting, thereby increasing the service life of the battery of the energy storage cabinet and improving the safety and reliability of the system.

[0139] The utility model also provides an energy storage system, comprising the above energy storage cabinet and an energy management system, wherein the energy management system is used to perform energy management on batteries in each energy storage cabinet.

[0140] In the utility model, a delayed protection function is provided for the battery in the dual power switching circuit of the energy storage system. During the switching process between the DC power supply and the AC power supply, the battery backup time is set by delaying the opening or closing of the relay contacts to control the length of time the battery supplies power to the load, thereby avoiding the problem of battery power loss caused by long-term battery backup and extending the battery life. At the same time, the uninterrupted switching between the AC power supply and the DC power supply ensures the reliability of the DC load power supply.

[0141] Finally, it should be noted that the above embodiments are only specific implementation methods of the utility model, which are used to illustrate the technical solution of the utility model, rather than to limit it. The protection scope of the utility model is not limited thereto. Although the utility model is described in detail with reference to the above embodiments, those skilled in the art should understand that any technician familiar with the technical field can still modify the technical solution recorded in the above embodiments within the technical scope disclosed by the utility model, or can easily think of changes, or make equivalent replacements for some of the technical features therein; and these modifications, changes or replacements do not make the essence of the corresponding technical solution deviate from the spirit and scope of the technical solution of the embodiment of the utility model, and should be included in the protection scope of the utility model. Therefore, the protection scope of the utility model shall be based on the protection scope of the claims.

Claims

1. A power control circuit, characterized in that: include: An AC / DC module, a DC / DC module and a control module, wherein the control module includes at least one relay; The positive output terminal of the DC / DC module is connected to the positive output terminal of the AC / DC module and the positive electrode of the load through the contact of the at least one relay; The negative output terminal of the DC / DC module is connected to the negative output terminal of the AC / DC module and the negative electrode of the load; The control module is used to control the conduction time between the positive output terminal of the DC / DC module and the positive electrode of the load by delaying the opening or closing of the corresponding contacts of each relay; The DC / DC module has a DC input terminal, the DC input terminal is used to connect to a battery, and the DC / DC module is used to adjust the DC power output by the battery to DC power of a target working voltage; The AC / DC module has an AC input terminal, which is used to connect to the AC mains. The AC / DC module is used to convert the AC mains into DC power of a target working voltage.

2. The power control circuit according to claim 1, characterized in that: The control module also includes a diode unit; The first input end of the diode unit is connected to the positive output end of the AC / DC module, the second input end of the diode unit is connected to the positive output end of the DC / DC module, and the output end of the diode unit is connected to the positive electrode of the load; The diode unit is used to output the voltage of the first input terminal or the voltage of the second input terminal to the positive electrode of the load.

3. The power control circuit according to claim 2, characterized in that: The control module comprises a first power-off delay relay, the contact of the first power-off delay relay being a first delayed opening and closing contact; The two ends of the coil in the first power-off delay relay are respectively connected to the positive and negative output ends of the AC / DC module; The first end of the first time-delayed opening normally-making contact is connected to the positive output end of the DC / DC module, and the second end of the first time-delayed opening normally-making contact is connected to the second input end of the diode unit.

4. The power control circuit according to claim 2, characterized in that: The control module includes a first power-off delay relay and a second power-off delay relay, wherein the contact of the first power-off delay relay is a first delayed opening and closing contact, and the contact of the second power-off delay relay is a second delayed opening and closing contact; The two ends of the coil in the first power-off delay relay are respectively connected to the positive and negative output ends of the AC / DC module; The first end of the second time-delayed opening and closing contact is connected to the first end of the coil of the second power-off delay relay and the positive output end of the DC / DC module, and the second end of the second time-delayed opening and closing contact is connected to the second input end of the diode unit; The first end of the first delayed opening make contact is connected to the second end of the coil of the second power-off delay relay, and the second end of the first delayed opening make contact is connected to the negative output end of the DC / DC module.

5. The power control circuit according to claim 2, characterized in that: The control module includes a first solid-state relay, a second solid-state relay and a first power-on delay relay, the contact of the first solid-state relay is a first normally closed contact, the contact of the second solid-state relay is a first normally open contact, and the contact of the first power-on delay relay is a first delayed opening break contact; The two ends of the coil in the first solid-state relay are respectively connected to the positive and negative output terminals of the AC / DC module; The first end of the first normally closed contact is connected to the positive output end of the DC / DC module, and the second end of the first normally closed contact is connected to the first end of the coil of the first power-on delay relay, the first end of the first delayed breaking contact, and the first end of the first normally open contact; The second end of the first normally open contact is connected to the second input end of the diode unit; The second end of the first delayed-off break contact is connected to the first end of the coil of the second solid-state relay, and the second end of the coil of the second solid-state relay is connected to the second end of the coil of the first power-on delay relay and the negative output end of the DC / DC module.

6. The power control circuit according to claim 2, characterized in that: The control module includes a first intermediate relay and a first time relay, and the contact of the first intermediate relay is a first normally open contact; The two ends of the coil in the first intermediate relay are respectively connected to the positive and negative output ends of the AC / DC module; The first time relay comprises a first circuit input end, a second circuit input end, a third circuit input end and a first circuit output end; The first end of the first normally open contact is connected to the second loop input end and the positive output end of the DC / DC module; The second end of the first normally open contact is connected to the first loop input end; The third loop input end is connected to the negative output end of the DC / DC module, and the first loop output end is connected to the second input end of the diode unit.

7. The power control circuit according to claim 2, characterized in that: The control module comprises a first intermediate relay and a first power-on delay relay, the contact of the first intermediate relay is a first normally closed contact, and the contact of the first power-on delay relay is a first delayed opening break contact; The two ends of the coil in the first intermediate relay are respectively connected to the positive and negative output ends of the AC / DC module; The first end of the first normally closed contact is connected to the positive output end of the DC / DC module, and the second end of the first normally closed contact is connected to the first end of the coil of the first power-on delay relay and the first end of the first delayed opening break contact; The second end of the first delayed-open break contact is connected to the second input end of the diode unit; The second end of the coil of the first power-on delay relay is connected to the negative output end of the DC / DC module.

8. The power control circuit according to claim 7, characterized in that: The control module further includes an energy storage capacitor, which is arranged between the positive electrode of the load and the negative electrode of the load, and is used to supply power to the load during the switching delay period between the AC / DC module and the DC / DC module.

9. The power control circuit according to claim 2, characterized in that: The control module includes a battery management system BMS, a first intermediate relay and a second intermediate relay, wherein the contact of the first intermediate relay is a first normally open contact, and the contact of the second intermediate relay is a first normally closed contact; Two ends of the coil of the first intermediate relay are respectively connected to the positive and negative output ends of the AC / DC module; Both ends of the first normally open contact are connected to the digital input terminals of the BMS; The coil of the second intermediate relay is connected to the high-side digital output terminal of the BMS, and the output voltage of the high-side output terminal is the power supply voltage of the BMS; A first end of the first normally closed contact is connected to the positive output end of the DC / DC module, and a second end of the first normally closed contact is connected to the second input end of the diode unit.

10. The power control circuit according to claim 2, characterized in that: The control module includes a battery management system BMS, a DC circuit breaker and a first intermediate relay, wherein the contact of the first intermediate relay is a first normally open contact; Two ends of the coil of the first intermediate relay are respectively connected to the positive and negative output ends of the AC / DC module; Both ends of the first normally open contact are connected to the digital input terminals of the BMS; The positive output end of the DC / DC module is connected to the second input end of the diode unit after passing through the DC circuit breaker, and the negative output end of the DC / DC module is connected to the negative pole of the load after passing through the DC circuit breaker.

11. The power control circuit according to any one of claims 1 to 10, characterized in that: The DC / DC module includes a working voltage protection unit, which is used to stop outputting direct current when the output voltage of the DC / DC module is less than a voltage threshold, and the voltage threshold is greater than the undervoltage protection value of the battery of the energy storage cabinet.

12. The power control circuit according to any one of claims 1 to 10, characterized in that: A self-locking button is provided on the loop where the positive output terminal of the DC / DC module is located, and the self-locking button is used to provide a black start function and an emergency shutdown function.

13. An energy storage cabinet, characterized in that: The invention comprises a power control circuit and a battery as claimed in any one of claims 1 to 12.

14. An energy storage system, characterized in that: It comprises several energy storage cabinets and an energy management system as claimed in claim 13, wherein the energy management system is used to perform energy management on the batteries in each energy storage cabinet.

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