Power supply system

Abstract

The invention provides a power supply system, and the system comprises an energy storage module which is provided with a grid-connected voltage output end and an off-grid voltage output end; the voltage transformation module is used for performing voltage transformation on the input initial voltage and outputting the transformed target voltage to the power supply end of the power supply system; the first switch module is used for controlling the voltage output by the grid-connected voltage output end of the energy storage module to be input into the voltage transformation module or controlling the voltage output by the off-grid voltage output end of the energy storage module to be input into the voltage transformation module; and the second switch module is used for controlling whether the voltage of the power grid is input to the power supply end of the power supply system. In the grid-connected power supply mode and the off-grid power supply mode of the energy storage module, the same voltage transformation module is adopted for voltage transformation, so that the technical problems that the size of a power supply system is increased and the cost is increased due to the fact that transformers need to be arranged at the grid-connected voltage output end and the off-grid voltage output end of the energy storage module respectively are solved.

Description

Technical Field

[0001] The present application relates to the field of power supply technology, and in particular to a power supply system. Background Art

[0002] At present, due to the different power systems in different countries or regions, there are differences in grid voltage and wiring. At the same time, the output voltage range of the AC output side of the energy storage machine is relatively narrow and the wiring system is relatively fixed. Therefore, the energy storage machine is usually not suitable for all types of power grids. Therefore, in some special areas and occasions, it is necessary to connect an isolation transformer to the AC output side of the energy storage machine to adapt to different grid voltage and wiring requirements.

[0003] In the related technology, the energy storage machine has a grid-connected working mode and an off-grid working mode. The on-grid and off-grid switching is usually switched by an external automatic transfer switching equipment (ATS). Therefore, in the above scenario, the GRID output port and EPS output port of the energy storage machine need to be equipped with transformers respectively, and the voltage is transformed by the transformer and sent to the automatic transfer switching equipment, and finally the automatic transfer switching equipment selects the power supply mode for the load. However, the installation of transformers for the GRID output port and EPS output port of the energy storage machine leads to the problem of increased volume and cost of the power supply system. Summary of the invention

[0004] The present application provides a power supply system, which aims to solve the technical problem that transformers need to be respectively provided for the GRID output port and the EPS output port of the energy storage machine, thereby increasing the size of the power supply system and the cost.

[0005] In a first aspect, the present application provides a power supply system, comprising: An energy storage module, the energy storage module having a grid-connected voltage output terminal and an off-grid voltage output terminal; A voltage conversion module, which is used to convert the input initial voltage and output the converted target voltage to the power supply end of the power supply system; A first switch module, the first switch module is used to control the voltage input transformer module outputted by the grid-connected voltage output terminal of the energy storage module, or to control the voltage input transformer module outputted by the off-grid voltage output terminal of the energy storage module; A second switch module, the second switch module is used to control whether the voltage of the power grid is input to the power supply end of the power supply system; Wherein, when the second switch module controls the voltage of the power grid to be input to the power supply end of the power supply system, the first switch module controls the voltage output of the grid-connected voltage output end of the energy storage module to be input to the transformer module; When the second switch module controls the voltage of the power grid to stop being input into the power supply end of the power supply system, the first switch module controls the voltage output from the off-grid voltage output end of the energy storage module to be input into the transformer module.

[0006] In some embodiments, when the grid loses power, the second switch module controls the voltage of the grid to stop inputting into the power supply end of the power supply system, and the first switch module controls the voltage outputted from the off-grid voltage output end of the energy storage module to input into the transformer module; When the grid receives power, the second switch module controls the voltage of the grid to be input to the power supply end of the power supply system, and the first switch module controls the voltage output from the grid-connected voltage output end of the energy storage module to be input to the transformer module.

[0007] In some embodiments, when the grid loses power, the second switch module controls the voltage of the grid to stop inputting into the power supply end of the power supply system at the first moment, and the first switch module controls the voltage outputted from the off-grid voltage output end of the energy storage module to input into the transformer module at the second moment; Among them, the first moment is before the second moment.

[0008] In some embodiments, when the grid receives power, the second switch module controls the voltage of the grid to be input into the power supply end of the power supply system at a third moment, and the first switch module controls the voltage output of the grid-connected voltage output end of the energy storage module to be input into the transformer module at a fourth moment; Among them, the third moment is before the fourth moment.

[0009] In some embodiments, the first switch module includes a first switch, a second switch, and a first control unit; The first switch is used to control the voltage input to the voltage transformation module of the grid-connected voltage output terminal of the energy storage module; The second switch is used to control the voltage input to the voltage transformation module of the off-grid voltage output terminal of the energy storage module; The first control unit is used for receiving a first control signal to control one of the first switch and the second switch to be closed.

[0010] In some embodiments, the second switch module includes a grid switch, a sampling unit, and a second control unit; The grid switch is used to control the voltage of the grid to be input to the power supply end of the power supply system, and the sampling unit is used to detect whether the grid has electricity and output a first sampling signal; The second control unit is used to output a first control signal to the first control unit in response to the first sampling signal.

[0011] In some embodiments, the first control unit is further configured to output a second control signal to the second control unit; The grid switch controls the voltage of the grid to be input to the power supply end of the power supply system when the second control signal is valid and the grid has power.

[0012] In some embodiments, the first control unit has a first communication output and a first communication input, and the second control unit has a second communication output and a second communication input; The second communication output terminal is connected to the first communication input terminal to output a first control signal to the first control unit; The first communication output terminal is connected to the second communication input terminal to output a second control signal to the second control unit.

[0013] In some embodiments, a first passive switch is provided between the second communication output terminal and the first communication input terminal, and a second passive switch is provided between the first communication output terminal and the second communication input terminal.

[0014] In some embodiments, when the first control signal is valid, the first passive switch is closed; when the first control signal is invalid, the first passive switch is opened; When the second control signal is valid, the second passive switch is closed; when the second control signal is invalid, the second passive switch is opened.

[0015] In the present application, when the second switch module controls the voltage input of the power grid to the power supply end of the power supply system, the first switch module is used to control the voltage output of the grid-connected voltage output end of the energy storage module to input the voltage input to the transformer module, so that the transformer module transforms the voltage output of the grid-connected voltage output end and sends it to the power supply end of the power supply system, thereby realizing the grid-connected power supply mode of the energy storage module; and when the second switch module controls the voltage of the power grid to stop inputting the power supply end of the power supply system, the first switch module is used to control the voltage output of the off-grid voltage output end of the energy storage module to input the voltage input to the transformer module, so that the transformer module transforms the voltage output of the off-grid voltage output end and sends it to the power supply end of the power supply system, thereby realizing the off-grid power supply mode of the energy storage module.

[0016] That is to say, in the grid-connected power supply mode and the off-grid power supply mode of the energy storage module, the present application adopts the same transformer module to convert the voltage output by the grid-connected voltage output terminal and the off-grid voltage output terminal, thereby avoiding the technical problem of respectively providing transformers for the grid-connected voltage output terminal and the off-grid voltage output terminal of the energy storage module, thereby increasing the size of the power supply system and the cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0018] Figure 1is a schematic diagram of a power supply system provided in an embodiment of the present application; Figure 2 This is a schematic diagram of an action sequence of the first switch module and the second switch module provided in an embodiment of the present application; Figure 3 is another schematic diagram of a power supply system provided in an embodiment of the present application; Figure 4 is another schematic diagram of a power supply system provided in an embodiment of the present application; Figure 5 It is another schematic diagram of the power supply system provided in an embodiment of the present application.

[0019] Among them, 10 is an energy storage module, 20 is a transformer module, 30 is a first switch module, 31 is a first switch, 32 is a second switch, 33 is a first control unit, 40 is a second switch module, 41 is a grid switch, 42 is a sampling unit, and 43 is a second control unit; Grid-connected voltage output terminal GRID, off-grid voltage output terminal EPS, power supply terminal OUT, first control signal INV_DI, second control signal GRID_DI, first communication input terminal RX1, first communication output terminal TX1, second communication input terminal RX2, second communication output terminal TX2, first passive switch GRID_DO, second passive switch INV_DO. DETAILED DESCRIPTION

[0020] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0021] In the description of the present invention, the word "exemplary" is used to mean "used as an example, illustration, or description". Any embodiment described in this application as "exemplary" is not necessarily to be construed as being preferred or advantageous over other embodiments. The following description is given to enable any person skilled in the art to implement and use the present invention. In the following description, details are listed for the purpose of explanation. It should be understood that a person of ordinary skill in the art can recognize that the present invention can be implemented without using these specific details. In other instances, well-known structures and processes are not elaborated in detail to avoid obscuring the description of the present invention with unnecessary details. Therefore, the present invention is not intended to be limited to the embodiments shown, but is consistent with the widest scope consistent with the principles and features disclosed in this application.

[0022] The embodiment of the present application provides a power supply system, which is described in detail below.

[0023] First, see Figure 1 , Figure 1 A schematic diagram of a power supply system in an embodiment of the present application is shown, wherein the power supply system includes an energy storage module 10 , a transformer module 20 , a first switch module 30 and a second switch module 40 .

[0024] Specifically, the energy storage module 10 can output an AC voltage so that the transformer module 20 can transform the AC voltage, thereby realizing grid-connected power supply in the grid-connected working mode or realizing off-grid power supply in the off-grid working mode. Generally, the energy storage module 10 may include an energy storage battery and an inverter, and the DC voltage of the energy storage battery is converted into an AC voltage output by the inverter. For example, the energy storage battery may include but is not limited to lead-acid batteries, lithium-ion batteries, sodium-sulfur batteries, nickel-hydrogen batteries, nickel-cadmium batteries, lithium-iron batteries, etc., and the inverter may include but is not limited to series inverters, parallel inverters, half-bridge inverters, full-bridge inverters, etc.

[0025] The energy storage module 10 has a grid-connected voltage output terminal GRID and an off-grid voltage output terminal EPS. Generally, the phase of the AC voltage outputted by the grid-connected voltage output terminal GRID is controllable, while the phase of the AC voltage outputted by the off-grid voltage output terminal EPS is uncontrollable. When the energy storage module 10 works in the grid-connected working mode, the energy storage module 10 can detect the voltage phase of the grid and change the phase of the AC voltage outputted by the grid-connected voltage output terminal GRID, so that the AC voltage outputted by the grid-connected voltage output terminal GRID is aligned with the voltage phase of the grid, and finally the voltage is connected to the grid when the voltage phase is aligned, so as to supply power to the load through the energy storage module 10 and the grid; and when the energy storage module 10 works in the off-grid working mode, the energy storage module 10 can directly output the AC voltage outputted by the off-grid voltage output terminal EPS, and after the transformer module 20 transforms the AC voltage outputted by the off-grid voltage output terminal EPS, the load can be supplied with power.

[0026] The transformer module 20 is used to transform the input initial voltage and output the transformed target voltage to the power supply terminal OUT of the power supply system, so that the transformed target voltage meets the requirements of the power system, grid voltage, wiring system, etc. of the corresponding country or region. For example, the transformer module 20 can convert the 80V AC voltage output by the grid-connected voltage output terminal GRID of the energy storage module 10 into a 110V AC voltage, and connect the 110V AC voltage to the grid 110V AC voltage to supply power to the load; for another example, the transformer module 20 can convert the 80V AC voltage output by the off-grid voltage output terminal EPS of the energy storage module 10 into a 240V AC voltage, and supply power to the load through the 240V AC voltage.

[0027] Exemplarily, the transformer module 20 may include, but is not limited to, various types of transformers such as a double-winding transformer, a three-winding transformer, and an autotransformer.

[0028] The first switch module 30 is used to control the voltage output from the grid-connected voltage output terminal GRID of the energy storage module 10 to be input into the transformer module 20, or to control the voltage output from the off-grid voltage output terminal EPS of the energy storage module 10 to be input into the transformer module 20, so that the transformer module 20 can transform the voltage output from the grid-connected voltage output terminal GRID of the energy storage module 10, or the transformer module 20 can transform the voltage output from the off-grid voltage output terminal EPS of the energy storage module 10.

[0029] In some embodiments of the present application, the first switch module 30 may include a plurality of switches, for example, a switch is provided for each of the grid-connected voltage output terminal GRID and the off-grid voltage output terminal EPS, so as to respectively control whether the voltage outputted by the grid-connected voltage output terminal GRID and the off-grid voltage output terminal EPS is inputted into the transformer module 20. In some embodiments of the present application, the first switch module 30 may include a single switch, for example, the first switch module 30 may include a selection switch, and the selection switch selects the voltage outputted by one of the grid-connected voltage output terminal GRID and the off-grid voltage output terminal EPS to be inputted into the transformer module 20.

[0030] The second switch module 40 is used to control whether the voltage of the power grid is input to the power supply terminal OUT of the power supply system, so that when the voltage of the power grid is input to the power supply terminal OUT of the power supply system, it is combined with the energy storage module 10 for grid-connected power supply, or when the voltage of the power grid is not input to the power supply terminal OUT of the power supply system, the energy storage module 10 is used to supply power alone.

[0031] In some embodiments of the present application, the first switch module 30 can passively control whether the voltage of the power grid is input to the power supply terminal OUT of the power supply system, limited by whether the power grid has power. For example, when the power grid has power, the first switch module 30 controls the voltage of the power grid to be input to the power supply terminal OUT of the power supply system, and when the power grid loses power, the first switch module 30 controls the voltage of the power grid to stop being input to the power supply terminal OUT of the power supply system. In some embodiments of the present application, the second switch module 40 can actively control whether the voltage of the power grid is input to the power supply terminal OUT of the power supply system regardless of whether the power grid has power. For example, when the power grid has power, the second switch module 40 controls the voltage of the power grid to stop being input to the power supply terminal OUT of the power supply system, and the voltage output through the off-grid voltage output terminal EPS of the energy storage module 10 is input to the transformer module 20 and supplies power to the load.

[0032] Exemplarily, the first switch module 30 and the second switch module 40 may include but are not limited to relays or transistors with switching functions such as MOS tubes, triodes, and IGBT tubes.

[0033] It should be pointed out that the above description of the power supply system and its modules is only for the convenience of description and does not limit the present application to the scope of the embodiments. It can be understood that for those skilled in the art, after understanding the principle of the system, it is possible to arbitrarily combine the modules or form a subsystem to connect with other modules without deviating from this principle. For example, in the embodiment of the present application, the first switch module 30 and the second switch module 40 can be independently arranged from the transformer module 20 and the energy storage module 10; for another example, the first switch module 30 and the second switch module 40 can also be arranged in the transformer module 20 and the energy storage module 10. For example, the first switch module 30 can be arranged inside the energy storage module 10 (such as an inverter), and the second switch module 40 can be arranged inside the transformer module 20.

[0034] In the embodiment of the present application, when the second switch module 40 controls the voltage of the power grid to be input into the power supply terminal OUT of the power supply system, the first switch module 30 can control the voltage output from the grid-connected voltage output terminal GRID of the energy storage module 10 to be input into the transformer module 20, so that the transformer module 20 transforms the voltage output from the grid-connected voltage output terminal GRID and sends it to the power supply terminal OUT of the power supply system, thereby realizing grid-connected power supply of the energy storage module 10; and when the second switch module 40 controls the voltage of the power grid to stop being input into the power supply terminal OUT of the power supply system, the first switch module 30 can control the voltage output from the off-grid voltage output terminal EPS of the energy storage module 10 to be input into the transformer module 20, so that the transformer module 20 transforms the voltage output from the off-grid voltage output terminal EPS and sends it to the power supply terminal OUT of the power supply system, thereby realizing off-grid power supply of the energy storage module 10.

[0035] That is to say, the present application uses the same transformer module 20 for voltage conversion in both the grid-connected power supply mode and the off-grid power supply mode of the energy storage module 10, thereby avoiding the technical problem of respectively providing transformers for the grid-connected voltage output terminal GRID and the off-grid voltage output terminal EPS of the energy storage module 10, thereby causing an increase in the size of the power supply system and an increase in cost.

[0036] In some embodiments of the present application, when the grid loses power, the second switch module 40 controls the grid voltage to stop being input into the power supply terminal OUT of the power supply system, and the first switch module 30 controls the voltage output from the off-grid voltage output terminal EPS of the energy storage module 10 to be input into the transformer module 20. Therefore, after the transformer module 20 converts the voltage output from the off-grid voltage output terminal EPS of the energy storage module 10 and sends it to the power supply terminal OUT, the energy storage module 10 alone supplies power to the load; and when the grid is powered on, the second switch module 40 controls the grid voltage to be input into the power supply terminal OUT of the power supply system, and the first switch module 30 controls the voltage output from the grid-connected voltage output terminal GRID of the energy storage module 10 to be input into the transformer module 20. Therefore, after the transformer module 20 converts the voltage output from the grid-connected voltage output terminal GRID of the energy storage module 10 and sends it to the power supply terminal OUT, the grid and the energy storage module 10 jointly supply power to the load.

[0037] That is to say, the energy storage module 10 in the above embodiment is powered off-grid or on-grid depending on whether the grid has electricity. If the grid has electricity, the energy storage module 10 is on-grid powered to reduce the grid load; if the grid loses power, the energy storage module 10 is powered off-grid to ensure the normal operation of the load. It can be understood that in some possible embodiments, the second switch module 40 can also control the voltage of the grid to stop inputting the power supply terminal OUT of the power supply system when the grid has electricity, and the voltage output of the off-grid voltage output terminal EPS of the energy storage module 10 is converted by the transformer module 20 and sent to the power supply terminal OUT, and then the energy storage module 10 supplies power to the load alone.

[0038] In some embodiments of the present application, when the power grid loses power, the second switch module 40 controls the voltage of the power grid to stop being input into the power supply end OUT of the power supply system at the first moment, and the first switch module 30 controls the voltage output of the off-grid voltage output end EPS of the energy storage module 10 to be input into the transformer module 20 at the second moment; wherein the first moment is before the second moment.

[0039] For example, see Figure 2 , Figure 2 A schematic diagram of the action sequence of the first switch module 30 and the second switch module 40 in the embodiment of the present application is shown, wherein the power grid loses power at time t1, the second switch module 40 operates at time t2 to control the voltage of the power grid to stop inputting into the power supply terminal OUT of the power supply system, and the first switch module 30 operates at time t3 to control the voltage outputted by the off-grid voltage output terminal EPS of the energy storage module 10 to input into the transformer module 20, so that after time t3, the energy storage module 10 supplies power to the load in the off-grid mode. It can be seen that since the second switch module 40 operates before the first switch module 30 when the power grid loses power, the phenomenon that the voltage transformed by the transformer module 20 in the off-grid mode of the energy storage module 10 is input into the power grid can be avoided.

[0040] In some embodiments of the present application, when the power grid is powered, the second switch module 40 controls the voltage of the power grid to be input to the power supply terminal OUT of the power supply system at a third moment, and the first switch module 30 controls the voltage output of the grid-connected voltage output terminal GRID of the energy storage module 10 to be input to the transformer module 20 at a fourth moment; wherein the third moment is before the fourth moment.

[0041] For example, continue to see Figure 2 , Figure 2 A schematic diagram of the action sequence of the first switch module 30 and the second switch module 40 in the embodiment of the present application is shown. When the grid receives power at time t4, the second switch module 40 operates at time t5 to control the voltage input of the grid to the power supply end OUT of the power supply system, and the first switch module 30 operates at time t6 to control the voltage output of the grid-connected voltage output end GRID of the energy storage module 10 to input the voltage input transformer module 20. Therefore, after time t6, the grid and the energy storage module 10 supply power to the load in the grid-connected mode. It can be seen that since the second switch module 40 operates before the first switch module 30 when the grid receives power, it can be ensured that the load is supplied with power as soon as possible. At the same time, the energy storage module 10 can also control the phase of the AC voltage output from the grid-connected voltage output end GRID according to the voltage of the voltage, so as to ensure that the phase of the AC voltage output from the grid-connected voltage output end GRID is consistent with the grid voltage phase before the first switch module 30 operates.

[0042] In some embodiments of the present application, for example, for an embodiment in which the first switch module 30 includes a plurality of switches, see Figure 3 , Figure 3 Another schematic diagram of the power supply system in an embodiment of the present application is shown, wherein the first switch module 30 includes a first switch 31, a second switch 32 and a first control unit 33; the first switch 31 is used to control the voltage input to the transformer module 20 outputted by the grid-connected voltage output terminal GRID of the energy storage module 10; the second switch 32 is used to control the voltage input to the transformer module 20 outputted by the off-grid voltage output terminal EPS of the energy storage module 10; the first control unit 33 is used to receive a first control signal INV_DI to control one of the first switch 31 and the second switch 32 to be closed.

[0043] For example, when the second switch module 40 controls the voltage of the power grid to be input into the power supply terminal OUT of the power supply system, the first control signal INV_DI received by the first control unit 33 is a high-level signal "1". At this time, the first control unit 33 can control the first switch 31 to be closed and the second switch 32 to be opened, so that the voltage output from the grid-connected voltage output terminal GRID of the energy storage module 10 is input into the transformer module 20. After the transformer module 20 transforms the voltage output from the grid-connected voltage output terminal GRID and sends it to the power supply terminal OUT of the power supply system, the grid-connected power supply of the energy storage module 10 can be realized; and when the second switch module 40 controls the voltage of the power grid to stop inputting the power supply terminal OUT of the power supply system, the first control signal INV_DI received by the first control unit 33 is a low-level signal "0". At this time, the first control unit 33 can control the first switch 31 to be opened and the second switch 32 to be closed, so that the voltage output from the off-grid voltage output terminal EPS of the energy storage module 10 is input into the transformer module 20. After the transformer module 20 transforms the voltage output from the off-grid voltage output terminal EPS and sends it to the power supply terminal OUT of the power supply system, the off-grid power supply of the energy storage module 10 can be realized.

[0044] Exemplarily, the first switch 31 and the second switch 32 may be, but are not limited to, relays or transistors with switching functions such as MOS tubes, triodes, and IGBT tubes. The first control unit 33 may include a communication module (such as an R485 communication module) and a single-chip microcomputer. After the communication module receives the first control signal INV_DI, the single-chip microcomputer outputs a control signal for controlling the first switch 31 and the second switch 32.

[0045] In some embodiments of the present application, see Figure 4 , Figure 4 Another schematic diagram of the power supply system in an embodiment of the present application is shown, wherein the second switch module 40 includes a grid switch 41, a sampling unit 42 and a second control unit 43; the grid switch 41 is used to control the voltage input of the grid to the power supply terminal OUT of the power supply system, and the sampling unit 42 is used to detect whether the grid has electricity and output a first sampling signal; the second control unit 43 is used to output a first control signal INV_DI to the first control unit 33 in response to the first sampling signal.

[0046] For example, when the grid has power, the sampling unit 42 can output a first sampling signal indicating that the grid has power, so the second control unit 43 can output a first control signal INV_DI that is a high level signal "1" to the first control unit 33 in response to the first sampling signal, so that the first control unit 33 can control the first switch 31 to be closed and the second switch 32 to be opened; and when the grid loses power, the sampling unit 42 can output a first sampling signal indicating that the grid has no power, so the second control unit 43 can output a first control signal INV_DI that is a low level signal "0" to the first control unit 33 in response to the first sampling signal, so that the first control unit 33 can control the first switch 31 to be opened and the second switch 32 to be closed.

[0047] Exemplarily, the grid switch 41 may be but is not limited to a relay or a transistor with a switching function such as a MOS tube, a triode, an IGBT tube, etc. The sampling unit 42 may be but is not limited to a voltage sensor or a current sensor. The first control unit 33 may include a communication module and a single-chip microcomputer. After the single-chip microcomputer receives the first sampling signal, the single-chip microcomputer controls the communication module to output the first control signal INV_DI.

[0048] In some embodiments of the present application, see Figure 4 , wherein the first control unit 33 is further used to output a second control signal GRID_DI to the second control unit 43, and the second control signal GRID_DI can indicate whether the energy storage module 10 is ready to be connected to the grid (for example, exiting the off-grid working mode and entering the grid-connected working mode); wherein the grid switch 41 controls the voltage of the grid to be input to the power supply terminal OUT of the power supply system when the second control signal GRID_DI is valid and the grid has power.

[0049] It should be noted that when the grid receives power, if the grid switch 41 is simply controlled to be closed according to the grid power, the energy storage module 10 may not be ready for grid connection (for example, aligning the phase of the AC voltage); if the grid switch 41 is simply controlled to be closed according to the second control signal GRID_DI output by the energy storage module 10 to be ready for grid connection, there may be an abnormal phenomenon caused by the grid power failure. In the above embodiment, since the grid switch 41 controls the grid voltage to be input to the power supply terminal OUT of the power supply system when the second control signal GRID_DI is valid and the grid has power, it can ensure that the energy storage module 10 is ready for grid connection and the grid has power when the grid is connected to the grid voltage, thereby avoiding the abnormal phenomenon caused by the direct closing of the grid switch 41 when the energy storage module 10 is not ready for grid connection or the grid has no power.

[0050] In some embodiments of the present application, see Figure 4The first control unit 33 has a first communication output terminal TX1 and a first communication input terminal RX1, and the second control unit 43 has a second communication output terminal TX2 and a second communication input terminal RX2; the second communication output terminal TX2 is connected to the first communication input terminal RX1, so the second control unit 43 can output the first control signal INV_DI to the first control unit 33 through the wire connected between the second communication output terminal TX2 and the first communication input terminal RX1, so that the first control unit 33 can control the first switch 31 and the second switch 32 in response to the first control signal INV_DI; at the same time, the first communication output terminal TX1 is connected to the second communication input terminal RX2, so the first control unit 33 can output the second control signal GRID_DI to the second control unit 43 through the wire connected between the first communication output terminal TX1 and the second communication input terminal RX2, so that the second control unit 43 controls the grid switch 41 in combination with the second control signal GRID_DI being effective and whether the grid has electricity.

[0051] In some embodiments of the present application, see Figure 5 , Figure 5 Another schematic diagram of the power supply system in the embodiment of the present application is shown, wherein a first passive switch GRID_DO is provided between the second communication output terminal TX2 and the first communication input terminal RX1, and a second passive switch INV_DO is provided between the first communication output terminal TX1 and the second communication input terminal RX2. The switching state of the first passive switch GRID_DO can be controlled by the first control signal INV_DI, and the switching state of the second passive switch INV_DO can be controlled by the second control signal GRID_DI.

[0052] For example, when the first control signal INV_DI is valid, the first passive switch GRID_DO is closed, thereby ensuring that the first control signal INV_DI is transmitted to the first control unit 33; and when the first control signal INV_DI is invalid, the first passive switch GRID_DO is opened, thereby preventing the second control unit 43 from mistakenly sending the first control signal INV_DI to the first control unit 33. When the second control signal GRID_DI is valid, the second passive switch INV_DO is closed, thereby ensuring that the second control signal GRID_DI is transmitted to the second control unit 43; when the second control signal GRID_DI is invalid, the second passive switch INV_DO is opened, thereby preventing the first control unit 33 from mistakenly sending the second control signal GRID_DI to the second control unit 43.

[0053] It can be seen that the first passive switch GRID_DO and the second passive switch INV_DO in the above embodiment can better ensure the transmission of the first control signal INV_DI and the second control signal GRID_DI, which is beneficial to reduce the transmission delay and energy consumption of the first control signal INV_DI and the second control signal GRID_DI.

[0054] Now Figure 5 Take this as an example to illustrate the working process of the power supply system of this application: 1) When the grid is powered, the first switch 31 is in a closed state, and the energy storage module 10 is connected to the grid normally. At this time, the first passive switch GRID_DO is in a closed state, and the first control signal INV_DI is a closed signal of "1"; the second passive switch INV_DO is in a closed state, and the second control signal GRID_DI is a closed signal of "1".

[0055] 2) When the grid loses power, the grid switch 41 is immediately cut off, and the sampling unit 42 learns that the grid voltage is lost. The second control unit 43 controls the first passive switch GRID_DO to be disconnected, and the first control signal INV_DI is a disconnection signal of "0"; after the first control unit 33 receives the first control signal INV_DI, the second passive switch INV_DO is disconnected, and the second control signal GRID_DI is a disconnection signal of "0". The first control unit 33 controls the first switch 31 to be disconnected and the second switch 32 to be closed. The energy storage module 10 works in the off-grid output mode, and the AC voltage output by the energy storage module 10 supplies power to the load through the transformer module 20.

[0056] 3) When the grid receives power, the sampling unit 42 knows that the grid has power, and the second control unit 43 controls the first passive switch GRID_DO to close, and the first control signal INV_DI is a closing signal of "1". When the first control unit 33 receives the first control signal INV_DI, the energy storage module 10 exits the off-grid output mode, and at the same time, the second passive switch INV_DO is closed, and the second control signal GRID_DI is a closing signal of "1". After the second control unit 43 receives the second control signal GRID_DI, the grid switch 41 is closed, and the first control unit 33 controls the first switch 31 to be closed, and the energy storage module 10 enters the grid-connected mode, and the AC voltage output by the energy storage module 10 passes through the transformer and is connected to the grid to supply power to the load.

[0057] The basic concepts have been described above. Obviously, for those skilled in the art, the above detailed disclosure is only for example and does not constitute a limitation of the present application. Although not explicitly stated herein, those skilled in the art may make various modifications, improvements and amendments to the present application. Such modifications, improvements and amendments are suggested in the present application, so such modifications, improvements and amendments still belong to the spirit and scope of the exemplary embodiments of the present application.

[0058] At the same time, the present application uses specific words to describe the embodiments of the present application. For example, "one embodiment", "an embodiment", and / or "some embodiments" refer to a certain feature, structure or characteristic related to at least one embodiment of the present application. Therefore, it should be emphasized and noted that "one embodiment" or "an embodiment" or "an alternative embodiment" mentioned twice or more in different positions in this specification does not necessarily refer to the same embodiment. In addition, some features, structures or characteristics in one or more embodiments of the present application can be appropriately combined.

[0059] Similarly, it should be noted that in order to simplify the description of the disclosure of this application and thus help understand one or more embodiments of the invention, in the above description of the embodiments of this application, multiple features are sometimes combined into one embodiment, figure or description thereof. However, this disclosure method does not mean that the features required by the object of this application are more than the features mentioned in the claims. In fact, the features of the embodiments are less than all the features of the single embodiment disclosed above.

[0060] The above is a detailed introduction to a power supply system provided in an embodiment of the present application. Specific examples are used herein to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as a limitation on the present invention.

Claims

1. A power supply system, characterized in that: include: An energy storage module, wherein the energy storage module has a grid-connected voltage output terminal and an off-grid voltage output terminal; A voltage conversion module, the voltage conversion module is used to convert the input initial voltage and output the converted target voltage to the power supply end of the power supply system; A first switch module, the first switch module is used to control the voltage output from the grid-connected voltage output terminal of the energy storage module to be input into the transformer module, or to control the voltage output from the off-grid voltage output terminal of the energy storage module to be input into the transformer module; A second switch module, the second switch module is used to control whether the voltage of the power grid is input to the power supply end of the power supply system; Wherein, when the second switch module controls the voltage of the power grid to be input into the power supply end of the power supply system, the first switch module controls the voltage output from the grid-connected voltage output end of the energy storage module to be input into the transformer module; When the second switch module controls the voltage of the power grid to stop being input into the power supply end of the power supply system, the first switch module controls the voltage output from the off-grid voltage output end of the energy storage module to be input into the transformer module.

2. The power supply system according to claim 1, characterized in that: When the power grid loses power, the second switch module controls the voltage of the power grid to stop inputting into the power supply end of the power supply system, and the first switch module controls the voltage outputted from the off-grid voltage output end of the energy storage module to input into the transformer module; When the grid receives power, the second switch module controls the voltage of the grid to be input into the power supply end of the power supply system, and the first switch module controls the voltage output from the grid-connected voltage output end of the energy storage module to be input into the transformer module.

3. The power supply system according to claim 2, characterized in that: When the power grid loses power, the second switch module controls the voltage of the power grid to stop inputting into the power supply end of the power supply system at the first moment, and the first switch module controls the voltage outputted by the off-grid voltage output end of the energy storage module to input into the transformer module at the second moment; The first moment is before the second moment.

4. The power supply system according to claim 2, characterized in that: When the power grid receives power, the second switch module controls the voltage of the power grid to be input into the power supply end of the power supply system at a third moment, and the first switch module controls the voltage output from the grid-connected voltage output end of the energy storage module to be input into the transformer module at a fourth moment; Among them, the third moment is before the fourth moment.

5. The power supply system according to claim 1, characterized in that: The first switch module includes a first switch, a second switch and a first control unit; The first switch is used to control the voltage output from the grid-connected voltage output terminal of the energy storage module to be input into the voltage transformation module; The second switch is used to control the voltage output from the off-grid voltage output terminal of the energy storage module to be input into the voltage transformation module; The first control unit is used to receive a first control signal to control one of the first switch and the second switch to be closed.

6. The power supply system according to claim 5, characterized in that: The second switch module includes a grid switch, a sampling unit and a second control unit; The grid switch is used to control the voltage of the grid to be input to the power supply end of the power supply system, and the sampling unit is used to detect whether the grid has electricity and output a first sampling signal; The second control unit is configured to output the first control signal to the first control unit in response to the first sampling signal.

7. The power supply system according to claim 6, characterized in that: The first control unit is further configured to output a second control signal to the second control unit; Wherein, when the second control signal is valid and the grid has power, the grid switch controls the voltage of the grid to be input to the power supply end of the power supply system.

8. The power supply system according to claim 7, characterized in that: The first control unit has a first communication output terminal and a first communication input terminal, and the second control unit has a second communication output terminal and a second communication input terminal; The second communication output terminal is connected to the first communication input terminal to output a first control signal to the first control unit; The first communication output terminal is connected to the second communication input terminal to output a second control signal to the second control unit.

9. The power supply system according to claim 8, characterized in that: A first passive switch is provided between the second communication output terminal and the first communication input terminal, and a second passive switch is provided between the first communication output terminal and the second communication input terminal.

10. The power supply system according to claim 9, characterized in that: When the first control signal is valid, the first passive switch is closed; when the first control signal is invalid, the first passive switch is opened; When the second control signal is valid, the second passive switch is closed; when the second control signal is invalid, the second passive switch is opened.

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