Dual power supply switching circuit and power supply

Abstract

This invention discloses a dual-power supply switching circuit and power supply. When the mains power is normal, the voltage conversion module converts the mains power to supply power to the first switching circuit and control module, while the energy storage module supplies power to the load. When the mains power is abnormal, the second switching circuit is manually closed, and the voltage conversion module receives the energy storage module voltage through the second switching circuit. The voltage conversion module then converts the energy storage module voltage to supply power to the first switching circuit and control module. Subsequently, the control module first controls the third switching circuit to close, and then controls the second switching circuit to open, allowing the voltage conversion module to receive the energy storage module voltage through the third switching circuit. When the mains power returns to normal, the control module controls the third switching circuit to open, and the voltage conversion module converts the mains power to supply power to the first switching circuit and control module. This invention proposes an AC / DC switching power supply operation strategy through electrical design to achieve AC / DC switching power supply under different conditions, realizing the black-start function of the energy storage battery system.

Description

TECHNICAL FIELD

[0001] The present application relates to the internal power supply safety of energy storage system field, and particularly relates to a dual-path power supply switching circuit and power supply. BACKGROUND

[0002] Energy storage is crucial in power consumption, and the power system is a steady-state balanced system. The energy storage power station adjusts and buffers between various power energy and power demand, and has the function of a "water storage pool", which can effectively improve the system voltage regulation and frequency modulation capability. With the continuous advancement of the parity process of wind power and photovoltaic new energy, the installed capacity of new energy is continuously increasing. New energy generation has the characteristics of intermittency and instability, and the energy consumption problem caused thereby is increasingly prominent. The construction of energy storage power stations can be used for peak clipping and improving power supply reliability. New energy + energy storage has become a development trend, which is conducive to the rapid development of the energy storage power station industry.

[0003] However, some energy storage power stations are often located in remote areas and have limited self-help capabilities. Once the external power grid fails and the city power disappears, it will have a great impact on the normal operation of the energy storage system. Therefore, it is necessary for the energy storage power station to have a black start function. SUMMARY

[0004] Therefore, the technical problem to be solved by the present application is to overcome the defect that the existing energy storage power station is often located in a remote area and has limited self-help capability, so as to provide a dual-path power supply switching circuit and power supply.

[0005] To achieve the above purpose, the present application provides the following technical scheme:

[0006] In a first aspect, embodiments of the present invention provide a dual-power supply switching circuit, comprising: a voltage conversion module, a control module, a first switching circuit, a second switching circuit, and a third switching circuit. The first input terminal of the voltage conversion module is connected to the mains power supply. The second input terminal of the voltage conversion module is connected to the positive output terminal of an energy storage module via the second and third switching circuits. The third input terminal of the voltage conversion module is connected to the negative output terminal of the energy storage module. The output terminal of the voltage conversion module is connected to the power supply terminals of the first and third switching circuits and the control module, respectively. The two input terminals of the first switching circuit are connected to the positive and negative output terminals of the energy storage module, respectively. The two output terminals of the first switching circuit are connected to the two power supply terminals of the load. When the mains power supply is normal, the first and second switching circuits are in a disconnected state. In the open state, the voltage conversion module converts mains power into a supply voltage, which powers the first switching circuit and the control module. The first switching circuit is controlled by the control module to be in a closed state through fixed logic, and the energy storage module supplies power to the load. When the mains power is abnormal, the second switching circuit is manually closed. The voltage conversion module then receives the voltage from the energy storage module through the second switching circuit. The voltage conversion module converts the output voltage of the energy storage module into a supply voltage, which powers the first switching circuit and the control module. After the control module is powered on, it sequentially controls the third switching circuit to close and the second switching circuit to open. The voltage conversion module then receives the voltage from the energy storage module through the third switching circuit. When the mains power returns to normal, the control module controls the third switching circuit to open.

[0007] In one embodiment, the first switching circuit includes: a positive contactor, a negative contactor, a first positive normally open contact, and a first negative normally open contact. The input terminal of the positive contactor is connected to the positive output terminal of the energy storage module, and the output terminal of the positive contactor is connected to the positive power supply terminal of the load. The positive power supply terminal of the positive contactor is connected to the positive output terminal of the voltage conversion module via the first positive normally open contact, and the negative power supply terminal of the positive contactor is connected to the negative output terminal of the voltage conversion module. Similarly, the input terminal of the negative contactor is connected to the negative output terminal of the energy storage module, and the output terminal of the negative contactor is connected to the negative power supply terminal of the load. The positive power supply terminal of the negative contactor is connected to the positive output terminal of the voltage conversion module via the first negative normally open contact, and the negative power supply terminal of the negative contactor is connected to the negative output terminal of the voltage conversion module.

[0008] In one embodiment, the second switching circuit includes: a first circuit breaker, the two ends of which are respectively connected to the positive output terminal of the energy storage module and the second positive input terminal of the voltage conversion module.

[0009] In an embodiment, the third switch circuit comprises: a DC contactor and a second positive normally open contact, wherein an input end of the DC contactor is connected with the positive output end of the energy storage module, an output end of the DC contactor is connected with the second positive input end of the voltage conversion module, a positive power supply end of the DC contactor is connected with the positive output end of the voltage conversion module through the second positive normally open contact, and a negative power supply end of the DC contactor is connected with the negative output end of the voltage conversion module.

[0010] In an embodiment, the dual-path power supply switching circuit further comprises: a second circuit breaker, the first AC input end and the second AC input end of the voltage conversion module are connected with the first output end and the second output end of the second circuit breaker respectively, and the L pole and the N pole of the second circuit breaker are connected with the live wire and the zero line of the mains respectively.

[0011] In an embodiment, the dual-path power supply switching circuit further comprises: a fuse, a first end of the fuse is connected with the positive output end of the energy storage module, and a second end of the fuse is connected with the input end of the DC contactor and the input end of the positive contactor respectively.

[0012] In a second aspect, an embodiment of the present application provides a power supply source, comprising: an energy storage module and the dual-path power supply switching circuit of the first aspect, wherein the energy storage module is connected with the load through the dual-path power supply switching circuit, and the mains is connected with the load through the dual-path power supply switching circuit.

[0013] In an embodiment, the energy storage module is a battery cluster composed of a plurality of battery modules connected in series.

[0014] In an embodiment, the control module is a BMS battery management system.

[0015] The technical scheme of the present application has the following advantages:

[0016] The dual-path power supply switching circuit and the power supply source provided by the present application have the following advantages: when the mains is normal, the voltage conversion module converts the mains to supply power to the first switch circuit and the control module, and the energy storage module supplies power to the load; when the mains is abnormal, the second switch circuit is manually closed, the voltage conversion module is connected with the voltage of the energy storage module through the second switch circuit, the voltage conversion module converts the voltage of the energy storage module to supply power to the first switch circuit and the control module, then the control module controls the third switch circuit to be closed and the second switch circuit to be disconnected in turn, and the voltage conversion module is connected with the voltage of the energy storage module through the third switch circuit; when the mains returns to normal, the control module controls the third switch circuit to be disconnected, and the voltage conversion module converts the mains to supply power to the first switch circuit and the control module. The present application realizes AC / DC switching power supply in different situations through electrical design, proposes an operation strategy of AC / DC switching power supply, and realizes the black start function of the energy storage battery system. BRIEF DESCRIPTION OF DRAWINGS

[0017] In order to more clearly illustrate the technical solutions of the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the description of the embodiments or the prior art. Obviously, the drawings described below are only some embodiments of the present application, and the ordinary skilled in the art can obtain other drawings according to these drawings without any creative effort.

[0018] Figure 1 The component diagram of one specific example of the dual-path power supply switching circuit provided by the embodiment of the present application;

[0019] Figure 2 The component diagram of another specific example of the dual-path power supply switching circuit provided by the embodiment of the present application;

[0020] Figure 3 The component diagram of one specific example of the power supply provided by the embodiment of the present application. EMBODIMENT

[0021] The technical solutions of the present application will be described clearly and completely below with reference to the drawings. Obviously, the described embodiments are only some of the embodiments of the present application, not all the embodiments. Based on the embodiments of the present application, all other embodiments obtained by the ordinary skilled in the art without any creative effort are within the scope of protection of the present application.

[0022] In the description of the present application, it should be noted that the orientations or positional relationships indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the devices or elements must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation of the present application. In addition, the terms "first", "second", "third" are only for the purpose of description, and cannot be understood as indicating or implying relative importance.

[0023] In the description of the present application, it should be noted that unless otherwise explicitly specified and limited, the terms "mounting", "connecting", "connection" should be understood broadly, for example, it can be fixed connection, or detachable connection, or integral connection; it can be mechanical connection, or electrical connection; it can be direct connection, or indirect connection through intermediate medium, or internal communication of two elements, it can be wireless connection, or wired connection. For the ordinary skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0024] Furthermore, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0025] Example 1

[0026] This invention provides a dual-power supply switching circuit, such as... Figure 1 As shown, it includes: voltage conversion module 1, control module 2, first switching circuit 3, second switching circuit 4, and third switching circuit 5.

[0027] like Figure 1 As shown, the first input terminal of voltage conversion module 1 is connected to the mains power, that is, the first AC input terminal and the second AC input terminal of voltage conversion module 1 are connected to the live wire and neutral wire of the mains power, respectively; the second input terminal of voltage conversion module 1 is connected to the positive output terminal of the energy storage module through the second switch circuit 4 and the third switch circuit 5, and the third input terminal of voltage conversion module 1 is connected to the negative output terminal of the energy storage module, that is, the second positive input terminal of voltage conversion module 1 is connected to the positive output terminal of the energy storage module through the second switch circuit 4 and the third switch circuit 5, respectively. The second negative input terminal is connected to the negative output terminal of the energy storage module; the output terminal of the voltage conversion module 1 is connected to the power supply terminal of the first switching circuit 3, the power supply terminal of the third switching circuit 5, and the power supply terminal of the control module 2, respectively. That is, the voltage output by the voltage conversion module 1 supplies power to the first switching circuit 3, the third switching circuit 5, and the control module 2; the two input terminals of the first switching circuit 3 are connected to the positive output terminal and the negative output terminal of the energy storage module, respectively, and the two output terminals of the first switching circuit 3 are connected to the two power supply terminals of the load. That is, the energy storage module supplies power to the load through the first switching circuit 3.

[0028] Specifically, the energy storage module of this invention is not limited to new energy sources such as solar energy, wind energy, and renewable energy, but can also be other devices with energy storage, which are not limited here.

[0029] Specifically, the voltage conversion module 1 in this embodiment of the invention converts the voltage output by the energy storage module or the mains power into a supply voltage. This supply voltage can supply power to the first switching circuit 3, the third switching circuit 5, and the control module 2. The voltage conversion module 1 can be a switching power supply, a flyback power supply, or other circuits with step-down and rectification functions, and is not limited here.

[0030] Specifically, the prior art only has the mains through the voltage conversion module 1 for voltage conversion for the first switch circuit 3, the control module 2 power supply, the first switch circuit 3 is controlled by the control module through fixed logic to close, the energy storage module discharges for the load power supply, but once the mains failure or disappear, the first switch circuit 3, the control module 2 power off, the first switch circuit 3 loses power and opens, the energy storage module stops for the load power supply, in order to realize the case of mains disappear or failure, the embodiment of the application sets the second switch circuit 4, the third switch circuit 5, realizes the energy storage module "self-help" measures, the voltage of the energy storage module is converted by the voltage conversion module 1 for the control module 2, the first switch circuit 3 power supply, thereby maintaining the stability of the load power supply, even realizing uninterrupted power supply.

[0031] Based on Figure 1 The application method of the double-way power supply switching circuit shown includes the following cases:

[0032] (1) When the mains is normal, the first switch circuit 3, the second switch circuit 4 are in the open state, the voltage conversion module 1 converts the mains into the power supply voltage, the power supply voltage supplies power for the first switch circuit 3, the control module 2, the first switch circuit 3 is controlled by the control module through fixed logic to be in the closed state, and the energy storage module supplies power for the load.

[0033] (2) When the mains is abnormal, manually close the second switch circuit 4, the voltage conversion module 1 accesses the energy storage module voltage through the second switch circuit, the energy storage module supplies power for the voltage conversion module 1, the voltage conversion module 1 converts the output voltage of the energy storage module into the power supply voltage, the power supply voltage supplies power for the first switch circuit 3, the control module 2, the control module 2 is powered on, the control module 2 controls the third switch circuit 5 to close and the second switch circuit 4 to open in turn, and the voltage conversion module 1 accesses the energy storage module voltage through the third switch circuit; when the mains is restored to normal, the control module 2 controls the third switch circuit 5 to open.

[0034] In a specific embodiment, as Figure 2As shown in the figure (taking voltage conversion module 1 as an example of a switching power supply), the first switching circuit 3 includes: a positive contactor KM1, a negative contactor KM2, a first positive normally open contact D01, and a first negative normally open contact D02. The input terminal of the positive contactor KM1 is connected to the positive output terminal of the energy storage module, and the output terminal of the positive contactor KM1 is connected to the positive power supply terminal of the load. The positive power supply terminal of the positive contactor KM1 is connected to the voltage conversion module 1 via the first positive normally open contact D01. The positive output terminal is connected, and the negative power supply terminal of the positive contactor KM1 is connected to the negative output terminal of the voltage conversion module 1; the input terminal of the negative contactor KM2 is connected to the negative output terminal of the energy storage module, the output terminal of the negative contactor KM2 is connected to the negative power supply terminal of the load, the positive power supply terminal of the negative contactor KM2 is connected to the positive output terminal of the voltage conversion module 1 through the first negative normally open contact D02, and the negative power supply terminal of the negative contactor KM2 is connected to the negative output terminal of the voltage conversion module 1.

[0035] Specifically, when the mains power is normal, the second switch circuit 4 ( Figure 2 QF2 in the middle), the third switch circuit 5 ( Figure 2 Both KM in the circuit are disconnected, and voltage conversion module 1 converts the mains power to the supply voltage. Figure 2 The power supply voltage (DC24V) powers the positive contactor KM1, the negative contactor KM2, and the control module 2. With the positive contactor KM1, the negative contactor KM2, the first normally open positive contact D01, and the first normally open negative contact D02 all closed, the energy storage modules (battery modules #1 to #16 in the diagram) supply power to the load through the positive contactor KM1 and the negative contactor KM2. In a specific embodiment, as shown... Figure 2 As shown in the figure (taking voltage conversion module 1 as a switching power supply as an example), the second switching circuit 4 includes: a first circuit breaker QF2, the two ends of which are respectively connected to the positive output terminal of the energy storage module and the second positive input terminal of the voltage conversion module 1.

[0036] like Figure 2 As shown, the third switching circuit 5 includes a DC contactor KM and a second positive normally open contact D03. The input terminal of the DC contactor KM is connected to the positive output terminal of the energy storage module, the output terminal of the DC contactor KM is connected to the second positive input terminal of the voltage conversion module 1, the positive power supply terminal of the DC contactor KM is connected to the positive output terminal of the voltage conversion module 1 through the second positive normally open contact D03, and the negative power supply terminal of the DC contactor KM is connected to the negative output terminal of the voltage conversion module 1. It should be noted that the first positive normally open contact D01, the first negative normally open contact D02, and the second positive normally open contact D03 are normally open relay output contacts within the control module, used to control the states of the positive contactor KM1, the negative contactor KM2, and the DC contactor KM through fixed logic control.

[0037] Specifically, when the mains is normal, the first circuit breaker QF2 and the DC contactor KM are both in the open state, the mains is converted by the voltage conversion module 1 to supply power for the positive contactor KM1, the negative contactor KM2 and the control module 2, the positive contactor KM1 and the negative contactor KM2 are controlled to be closed by the control module through fixed logic, and the energy storage module supplies power for the load through the positive contactor KM1 and the negative contactor KM2.

[0038] Specifically, when the mains disappears or fails, the voltage conversion module 1 no longer converts the mains into the supply voltage of the positive contactor KM1, the negative contactor KM2 and the control module 2, the positive contactor KM1 and the negative contactor KM2 are opened due to power loss, and the energy storage module no longer supplies power for the load through the positive contactor KM1 and the negative contactor KM2. In this case, in order to realize "self-rescue", the first circuit breaker QF2 needs to be manually closed first, at this time, the energy storage module is converted by the voltage conversion module 1 to supply power for the positive contactor KM1, the negative contactor KM2 and the control module 2, the positive contactor KM1 and the negative contactor KM2 are closed due to power supply, the control module 2 is powered and automatically controls the DC contactor KM to be closed and the first circuit breaker QF2 to be opened in turn, and the energy storage module supplies power for the load through the positive contactor KM1 and the negative contactor KM2, and the voltage conversion module 1 still converts the output voltage of the energy storage module into the supply voltage of the positive contactor KM1, the negative contactor KM2 and the control module 2.

[0039] Specifically, when the mains recovers to normal, the control module 2 automatically controls the DC contactor KM to be opened, the voltage conversion module 1 converts the mains into the supply voltage of the positive contactor KM1, the negative contactor KM2 and the control module 2, and the energy storage module still supplies power for the load through the positive contactor KM1 and the negative contactor KM2.

[0040] It should be noted that the energy storage module of the embodiment of the present application can be a battery cluster composed of a plurality of battery modules connected in series, the control module 2 can be a BMS battery management system, the voltage conversion module 1 can be a switching power supply, and the first switching circuit 3, the second switching circuit 4, the third switching circuit 5 and the switching voltage of the BMS battery management system are placed in the high-voltage box of the battery cluster, but this is only an example and is not limited thereto.

[0041] In a specific embodiment, as shown in Figure 2 The dual-path power supply switching circuit further includes a second circuit breaker QF1, the first AC input end and the second AC input end of the voltage conversion module 1 are connected with the first output end and the second output end of the second circuit breaker QF1 respectively, and the L pole and the N pole of the second circuit breaker QF1 are connected with the live wire and the zero wire of the mains respectively.

[0042] Specifically, the second circuit breaker QF1 is in a closed state, and the voltage conversion module 1 is connected to the AC 220V power supply through the second circuit breaker QF1.

[0043] In an embodiment, as shown in the figure, Figure 2 The dual power supply switching circuit further comprises a fuse FU1, a first end of the fuse FU1 is connected to the positive output end of the energy storage module, and a second end of the fuse FU1 is connected to the input end of the DC contactor KM and the input end of the positive contactor KM1, respectively. When the charging and discharging current of the energy storage module is too large or short-circuited, the fuse FU1 is disconnected to protect the load from damage.

[0044] Embodiment 2

[0045] The embodiment of the present application provides a power supply, as shown in the figure, Figure 3 The dual power supply switching circuit of the embodiment 1, wherein the energy storage module is connected to the load through the dual power supply switching circuit, and the AC power supply is connected to the load through the dual power supply switching circuit.

[0046] Specifically, the energy storage module supplies power to the load through the dual power supply switching circuit, when the AC power supply is normal, the AC power supply supplies power to the internal components of the dual power supply switching circuit, and when the AC power supply disappears, the energy storage module supplies power to the internal components of the dual power supply switching circuit.

[0047] In an embodiment, as shown in the figure, Figure 2 The energy storage module is a battery cluster composed of a plurality of battery modules (16 battery modules are taken as an example in the figure), and in addition, the energy storage module can also be other devices with energy storage, with discharging function, or with charging and discharging function, which is not limited here.

[0048] In an embodiment, when the energy storage module is a battery cluster, the control module 2 is a BMS battery management system.

[0049] Obviously, the above embodiments are only examples for clear illustration, and are not limited to the embodiments. For those skilled in the art, other different forms of changes or variations can be made on the basis of the above description. Here, it is not necessary and impossible to enumerate all the embodiments. The obvious changes or variations derived therefrom are still within the protection scope of the present application.

Claims

1. A dual supply switching circuit, characterized by, The application relates to a power supply device, which comprises a voltage conversion module, a control module, a first switch circuit, a second switch circuit and a third switch circuit. The first input end of the voltage conversion module is connected with commercial power, the second input end of the voltage conversion module is connected with the positive output end of an energy storage module through the second switch circuit and the third switch circuit, the third input end of the voltage conversion module is connected with the negative output end of the energy storage module, the output end of the voltage conversion module is connected with the power supply end of the first switch circuit, the power supply end of the third switch circuit and the power supply end of the control module, the two input ends of the first switch circuit are connected with the positive output end and the negative output end of the energy storage module, and the two output ends of the first switch circuit are connected with the two power supply ends of a load. When the commercial power is normal, the first switch circuit and the second switch circuit are in an open state, the voltage conversion module converts the commercial power into a power supply voltage, the power supply voltage is used for supplying power to the first switch circuit and the control module, the first switch circuit is controlled to be in a closed state by the control module through fixed logic, and the energy storage module is used for supplying power to the load. When the commercial power is abnormal, the second switch circuit is manually closed, the voltage conversion module is connected with the voltage of the energy storage module through the second switch circuit, the voltage conversion module converts the output voltage of the energy storage module into a power supply voltage, the power supply voltage is used for supplying power to the first switch circuit and the control module, the control module is powered on, the control module controls the third switch circuit to be closed and the second switch circuit to be opened in sequence, and the voltage conversion module is connected with the voltage of the energy storage module through the third switch circuit; when the commercial power is restored to normal, the control module controls the third switch circuit to be opened. The first switch circuit comprises a positive contactor, a negative contactor, a first positive normally-open contact and a first negative normally-open contact, the input end of the positive contactor is connected with the positive output end of the energy storage module, the output end of the positive contactor is connected with the positive power supply end of the load, the positive power supply end of the positive contactor is connected with the positive output end of the voltage conversion module through the first positive normally-open contact, the negative power supply end of the positive contactor is connected with the negative output end of the voltage conversion module, the input end of the negative contactor is connected with the negative output end of the energy storage module, the output end of the negative contactor is connected with the negative power supply end of the load, the positive power supply end of the negative contactor is connected with the positive output end of the voltage conversion module through the first negative normally-open contact, and the negative power supply end of the negative contactor is connected with the negative output end of the voltage conversion module. The second switch circuit comprises a first circuit breaker, and the two ends of the first circuit breaker are connected with the positive output end of the energy storage module and the second positive input end of the voltage conversion module respectively. The third switch circuit comprises a direct-current contactor and a second positive normally-open contact.

2. The dual supply power switching circuit of claim 1, wherein, ​ The input end of the direct current contactor is connected with the positive output end of the energy storage module, the output end of the direct current contactor is connected with the second positive input end of the voltage conversion module, the positive power supply end of the direct current contactor is connected with the positive output end of the voltage conversion module through the second positive normally open contact, and the negative power supply end of the direct current contactor is connected with the negative output end of the voltage conversion module.

3. The dual supply power switching circuit of claim 1, wherein, Further comprising: The first alternating current input end and the second alternating current input end of the voltage conversion module are connected with the first output end and the second output end of the second circuit breaker respectively, and the L pole and the N pole of the second circuit breaker are connected with the live wire and the zero line of the mains respectively.

4. The dual supply power switching circuit of claim 2, wherein, Further comprising: The first end of the fuse is connected with the positive output end of the energy storage module, and the second end of the fuse is connected with the input end of the direct current contactor and the input end of the positive contactor respectively.

5. A power supply, characterized by, Comprising: The energy storage module and the dual-path power supply switching circuit of any one of claims 1-4, wherein The energy storage module is connected with the load through the dual-path power supply switching circuit, and the mains is connected with the load through the dual-path power supply switching circuit.

6. The power supply of claim 5, wherein, The energy storage module is a battery cluster composed of a plurality of battery modules connected in series.

7. The power supply of claim 5, wherein, The control module is a BMS battery management system.

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