Energy storage device and energy storage system

Abstract

The utility model discloses an energy storage device and an energy storage system, and relates to the battery technology field, the energy storage device comprises an AC module, a DC module, a bus capacitor, a switch power supply box and a PCS energy storage control module, the AC module comprises an AC power supply unit and a rectification unit; the AC power supply unit is connected with the rectification unit, the rectification unit and the DC module are connected with the bus capacitor, the bus capacitor is connected with the switch power supply box, and the switch power supply box is connected with the PCS energy storage control module; the rectifying unit is used for converting alternating current voltage output by the alternating current power supply unit into direct current voltage, and the bus capacitor is used for filtering the direct current voltage. According to the utility model, the technical problem that the cost is high when the battery pack and the power grid supply power to the PCS in the energy storage device is solved.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and in particular to energy storage devices and energy storage systems. Background Art

[0002] When the power grid and battery pack supply power to the PCS in the energy storage device, two independent switching power supply boxes are usually required. One switching power supply box is connected to the power grid to convert the AC power of the power grid into the control power of the PCS; the other switching power supply box is connected to the battery pack to convert the DC power of the battery pack into the control power of the PCS. However, using two independent switching power supply boxes to supply power to the PCS has the technical problem of high cost.

[0003] The above content is only used to assist in understanding the technical solution of this application and does not constitute an admission that the above content is prior art. Utility Model Content

[0004] The main purpose of this application is to provide an energy storage device and an energy storage system, aiming to solve the technical problem of high cost when battery packs and power grids supply power to the PCS in the energy storage device.

[0005] To achieve the above objectives, the present invention proposes an energy storage device, which includes an AC module, a DC module, a bus capacitor, a switching power supply box, and a PCS energy storage control module. The AC module includes an AC power supply unit and a rectifier unit.

[0006] The AC power supply unit is connected to the rectifier unit, the rectifier unit and the DC module are both connected to the bus capacitor, the bus capacitor is connected to the switch power box, and the switch power box is connected to the PCS energy storage control module;

[0007] The rectifier unit is used to convert the AC voltage output by the AC power supply unit into a DC voltage, and the bus capacitor is used to filter the DC voltage.

[0008] In one embodiment, the rectifier unit includes a rectifier bridge and a first anti-reverse diode;

[0009] The AC power supply unit is connected to the rectifier bridge, the rectifier bridge is connected to the anode of the first anti-reverse diode, and the cathode of the first anti-reverse diode is connected to the bus capacitor.

[0010] In one embodiment, the DC module includes a DC power supply unit and a second anti-reverse diode, the DC power supply unit is connected to the anode of the second anti-reverse diode, and the cathode of the second anti-reverse diode is connected to the bus capacitor.

[0011] In one embodiment, when the voltage output by the DC power supply unit is an AC voltage, the second anti-reverse diode performs half-wave rectification on the AC voltage to convert the AC voltage into a DC voltage.

[0012] In one embodiment, the energy storage device further includes a voltage detection module, and the voltage detection module is connected to the DC module and the AC module respectively.

[0013] In one embodiment, the voltage detection module includes a first voltage detection unit, a second voltage detection unit, and a control unit, the control unit being connected to the first voltage detection unit and the second voltage detection unit, respectively, the first voltage detection unit being connected to the DC power supply unit in the DC module, and the second voltage detection unit being connected to the AC power supply unit in the AC module;

[0014] The first voltage detection unit is used to detect the voltage of the DC power supply unit, and the second voltage detection unit is used to detect the voltage of the AC power supply unit.

[0015] In one embodiment, when it is detected that the voltage output by the DC power supply unit is an AC voltage, the first voltage detection unit sends a first alarm signal to the control unit to prompt that the voltage of the DC power supply unit is abnormal.

[0016] In one embodiment, when it is detected that the voltage output by the AC power supply unit is a DC voltage, the second voltage detection unit sends a second alarm signal to the control unit to prompt that the voltage of the AC power supply unit is abnormal.

[0017] In one embodiment, the first voltage detection unit and the second voltage detection unit are operational amplifiers.

[0018] In addition, to achieve the above objectives, the present application also provides an energy storage system, which includes the energy storage device as described above.

[0019] The present invention provides an energy storage device, which includes an AC module, a DC module, a bus capacitor, a switching power supply box and a PCS energy storage control module. The AC module includes an AC power supply unit and a rectifier unit; the AC power supply unit is connected to the rectifier unit, the rectifier unit and the DC module are both connected to the bus capacitor, the bus capacitor is connected to the switching power supply box, and the switching power supply box is connected to the PCS energy storage control module; the rectifier unit is used to convert the AC voltage output by the AC power supply unit into a DC voltage, and the bus capacitor is used to filter the DC voltage.

[0020] Since the rectifier unit can convert the AC voltage of the AC power supply unit into a DC voltage, and the bus capacitor can also filter the DC voltage, making the DC voltage more stable, the AC module and the DC module can be connected to the same switching power supply box through the same bus capacitor, and the PCS energy storage control module is powered by the switching power supply box. There is no need to connect two independent switching power supply boxes separately, which reduces the cost of powering the PCS energy storage control module and solves the problem of high cost when the battery pack and the power grid supply power to the PCS in the energy storage device. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0022] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0023] Figure 1 This is a schematic diagram of a module of an embodiment of the energy storage device of the present utility model;

[0024] Figure 2 This is a schematic diagram of the AC module in the energy storage device of the present utility model;

[0025] Figure 3 This is a schematic diagram of a DC module in the energy storage device of the present utility model;

[0026] Figure 4 This is a module schematic diagram of another embodiment of the energy storage device of the present utility model;

[0027] Figure 5 This is a circuit connection diagram of an example of the energy storage device of the present invention.

[0028] The purpose, features and advantages of this application will be further explained in conjunction with the embodiments and with reference to the accompanying drawings.

[0029] Description of Figure Numbers:

[0030] 10. AC module; 20. DC module; 30. Bus capacitor; 40. Switching power supply box; 50. PCS energy storage control module; 11. AC power supply unit; 12. Rectifier unit; 121. Rectifier bridge; 122. Second anti-reverse diode; 21. DC power supply unit; 22. Second anti-reverse diode; 60. Voltage detection module; 61. First voltage detection unit; 62. Second voltage detection unit; 63. Control unit. DETAILED DESCRIPTION

[0031] It should be understood that the specific embodiments described herein are merely used to explain the technical solutions of the present application and are not intended to limit the present application.

[0032] It should be noted that all directional indications in the embodiments of the present application (such as up, down, left, right, front, back, etc.) are only used to explain the relative position relationship, movement status, etc. between the various components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0033] In addition, the descriptions of "first", "second", etc. in this application are for descriptive purposes only and should not be understood as indicating or implying their relative importance or implicitly indicating the number of the technical features indicated. Therefore, the features defined as "first" or "second" may explicitly or implicitly include at least one of such features. In addition, the technical solutions between the various embodiments can be combined with each other, but this must be based on the fact that they can be implemented by ordinary technicians in this field. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by this application.

[0034] In order to better understand the technical solution of the present application, a detailed description will be given below in conjunction with the accompanying drawings and specific implementation methods.

[0035] Energy storage devices are often used to smooth out peak and valley loads on the power grid. They can switch between two modes: the grid charges the battery pack in the energy storage device to store excess power, and the battery pack generates electricity for the grid to alleviate pressure on the grid. This requires the energy storage device to operate only when powered by the grid, or only when powered by the battery pack. To support both modes, the energy storage system requires a switching power supply (SPD) connected to the grid to convert AC power to PCS control power; a second SPD connected to the battery pack to convert DC power to PCS control power. However, using two separate SPDs to power the PCS presents technical challenges, such as high costs. Furthermore, using two SPDs can easily lead to wiring errors, such as connecting AC and DC in reverse, which can damage the energy storage device.

[0036] Based on this, the embodiment of the present application provides an energy storage device, referring to Figure 1 The energy storage device includes an AC module 10, a DC module 20, a bus capacitor 30, a switching power supply box 40 and a PCS energy storage control module 50, wherein the AC module 10 includes an AC power supply unit 11 and a rectifier unit 12;

[0037] The AC power supply unit 11 is connected to the rectifier unit 12, the rectifier unit 12 and the DC module 20 are both connected to the bus capacitor 30, the bus capacitor 30 is connected to the switch power box 40, and the switch power box 40 is connected to the PCS energy storage control module 50;

[0038] The rectifier unit 12 is used to convert the AC voltage output by the AC power supply unit 11 into a DC voltage, and the bus capacitor 30 is used to filter the DC voltage.

[0039] It should be noted that the AC module 10 can output an AC voltage and includes an AC power supply unit 11 and a rectifier unit 12. The AC power supply unit can be a power grid, and the AC power supply unit can output an AC voltage. The rectifier unit 12 can rectify the AC voltage output by the AC power supply unit to convert the AC voltage output by the AC power supply unit into a DC voltage.

[0040] The DC module 20 can output a DC voltage. The bus capacitor 30 can filter the DC voltage. The PCS energy storage control module 50 refers to the PCS (Power Conversion System) in the energy storage device. The PCS energy storage control module 50 can achieve bidirectional conversion of electrical energy.

[0041] The switch power supply box 40 is used to convert the received direct current into the control power required by the PCS energy storage control module 50 . The control power has the voltage and current required by the PCS energy storage control module 50 .

[0042] Since the rectifier unit 12 can convert the AC voltage of the AC power supply unit 11 into a DC voltage, and the bus capacitor 30 can also filter the DC voltage, making the DC voltage more stable, the AC module 10 and the DC module 20 can be connected to the same switching power supply box 40 through the same bus capacitor 30, and power is supplied to the PCS energy storage control module 50 through the switching power supply box 40, without the need to connect two independent switching power supply boxes respectively, thereby reducing the cost of powering the PCS energy storage control module.

[0043] In one possible embodiment, referring to Figure 2 , the rectifier unit 12 includes a rectifier bridge 121 and a first anti-reverse diode 122;

[0044] The AC power supply unit 11 is connected to the rectifier bridge 12 , the rectifier bridge 12 is connected to the anode of the first anti-reverse diode 122 , and the cathode of the first anti-reverse diode 122 is connected to the bus capacitor 30 .

[0045] It should be noted that the rectifier bridge 121 is used to rectify the AC voltage output by the AC power supply unit 11 to convert the AC voltage into a DC voltage. The first anti-reverse diode 122 can also be used to further rectify the voltage output by the rectifier bridge 121. Combining the rectifier bridge 121 and the first anti-reverse diode 122 for rectification can reduce the rectification cost. When the withstand voltage value of the rectifier bridge 121 is higher, the cost of the rectifier bridge 121 is higher. The higher the withstand voltage value, the better the rectification effect. The present invention can add the first anti-reverse diode 122 for further rectification, and then combine the rectifier bridge 121 and the first anti-reverse diode 122 for rectification, which can reduce the requirements for the withstand voltage value of the rectifier bridge 121. In addition, it can reduce the cost of rectification while ensuring the rectification effect, and ensure that the AC voltage can be converted into a DC voltage.

[0046] Further, in a feasible embodiment, referring to Figure 3 The DC module 20 includes a DC power supply unit 21 and a second anti-reverse diode 22 , the DC power supply unit 21 is connected to the anode of the second anti-reverse diode 22 , and the cathode of the second anti-reverse diode 22 is connected to the bus capacitor 30 .

[0047] It should be noted that the DC power supply unit 21 can be a battery pack, and the DC power supply unit 21 can transmit the DC voltage to the PCS energy storage control module 50 through the second anti-reverse diode 22 and the bus capacitor 30. The output end of the DC power supply unit 21 is connected to the anode of the second anti-reverse diode 22, and the cathode of the second anti-reverse diode 22 is connected to the bus capacitor 30.

[0048] In the case where the voltage input to the input end of the DC power supply unit 21 is an AC voltage, the second anti-backlash diode 22 performs half-wave rectification on the AC voltage to convert the AC voltage into a DC voltage.

[0049] Since there may be wiring errors, for example, the DC power supply unit 21 and the AC power supply unit 11 may be connected to each other in reverse, that is, the device that provides AC power (for example, a power grid, etc.) should be connected to the rectifier bridge as an AC power supply unit, but the device that provides AC power may be mistakenly connected to the second anti-reverse diode 22 in the DC module, and / or the device that provides DC power (for example, a battery pack, etc.) should be connected to the second anti-reverse diode as a DC power supply unit, but the device that provides DC power may be mistakenly connected to the rectifier bridge 121. When the above situation exists, it indicates that there is a wiring error in the energy storage device.

[0050] When there is a wiring error, the voltage output by the DC power supply unit 21 may be an AC voltage. Since the DC power supply unit 21 is connected to the second anti-reverse diode 22, even if there is a wiring error, the second anti-reverse diode 22 can perform half-wave rectification on the AC voltage output by the DC power supply unit 21 to convert the AC voltage output by the DC power supply unit 21 into a DC voltage, thereby avoiding wiring errors causing energy storage device failure, and / or causing damage to the switching power box 40, the PCS energy storage control module 50, etc., thereby affecting the reliability of the energy storage device.

[0051] If the voltage output by the AC power supply unit 11 is a DC voltage, this indicates that the energy storage device has also been miswired. Since the AC power supply unit 11 is connected to the rectifier bridge 121, the DC voltage can also pass through this rectifier bridge 121. Furthermore, the DC voltage output by the AC power supply unit 11 can be transmitted to the PCS energy storage control module 50 through the rectifier bridge 121, the first anti-reverse diode 122, the bus capacitor 30, and the switching power supply box 40. Therefore, even if the AC and DC are connected incorrectly, power can still be supplied to the PCS energy storage control module 50, thus achieving wiring fault tolerance.

[0052] Further, in one possible embodiment, referring to Figure 4 The energy storage device further includes a voltage detection module 60 , which is connected to the DC module 20 and the AC module 10 respectively.

[0053] The voltage detection module includes a first voltage detection unit 61, a second voltage detection unit 62, and a control unit 63. The control unit 63 is connected to the first voltage detection unit 61 and the second voltage detection unit 62, respectively. The first voltage detection unit 61 is connected to the DC power supply unit 21 in the DC module 20, and the second voltage detection unit 62 is connected to the AC power supply unit 11 in the AC module 10.

[0054] The first voltage detection unit 61 is used to detect the voltage of the DC power supply unit 21 , and the second voltage detection unit 62 is used to detect the voltage of the AC power supply unit 11 .

[0055] It should be noted that since AC / DC wiring errors may occur in the energy storage device, to reduce the impact of such errors, a voltage detection module can be used to detect whether there are AC / DC wiring errors in the energy storage device. In addition to detecting whether there are AC / DC errors, the voltage detection module can also detect whether the voltage in the DC power supply unit 21 is stable, as well as whether the voltage in the AC power supply unit 11 is stable. For example, if the voltage detection module detects a sudden increase in the voltage in the DC power supply unit 21 and / or a sudden increase in the voltage in the AC power supply unit 11, it indicates that the voltage of the DC power supply unit 21 is unstable.

[0056] Furthermore, when it is detected that the voltage output by the DC power supply unit 21 is an AC voltage, the first voltage detection unit 61 sends a first alarm signal to the control unit 63 to prompt that the voltage of the DC power supply unit 21 is abnormal.

[0057] When it is detected that the voltage output by the AC power supply unit 11 is a DC voltage, the second voltage detection unit 62 sends a second alarm signal to the control unit 63 to prompt that the voltage of the AC power supply unit 11 is abnormal.

[0058] The first voltage detection unit 61 can be an operational amplifier. The first voltage detection unit 61 can detect the voltage waveform of the DC power supply unit 21 to detect whether the voltage of the DC power supply unit 21 is a DC voltage. When the voltage waveform is a sine wave, it means that the voltage output by the DC power supply unit 21 is an AC voltage, and the DC power supply unit input is abnormal. A first alarm signal can be sent to the control unit 63.

[0059] The first alarm signal is an electrical signal output by the first voltage detection unit 61 to indicate an abnormal output of the DC power supply unit 21. The first alarm signal may be a voltage jump signal, for example, and is not specifically limited in this embodiment. The first voltage detection unit 61 sends the first alarm signal to the control unit 63, thereby indicating an abnormal output of the DC power supply unit, thereby controlling the energy storage device to shut down in a timely manner.

[0060] The second voltage detection unit 62 can be an operational amplifier, and then the second voltage detection unit 62 can detect the voltage waveform of the AC power supply unit 11 to detect whether the voltage of the AC power supply unit 11 is an AC voltage. When the voltage waveform is a sine wave, it means that the voltage output by the AC power supply unit 11 is an AC voltage. When the voltage waveform corresponding to the AC power supply unit is a straight line, or a straight line with slight fluctuations, it means that the detected voltage of the AC power supply unit 11 is a DC voltage, which means that the voltage output by the AC power supply unit 11 is abnormal, and a second alarm signal can be sent to the control unit 63.

[0061] The second alarm signal is an electrical signal output by the second voltage detection unit 62 to indicate an abnormal output of the AC power supply unit 11. The second alarm signal may be a voltage jump signal, for example, and is not specifically limited in this embodiment. The second voltage detection unit 62 sends the second alarm signal to the control unit 63, thereby indicating an abnormal output of the AC power supply unit and facilitating timely shutdown of the energy storage device.

[0062] The present application detects the voltage waveforms corresponding to the AC power supply unit 11 and the DC power supply unit 21, thereby being able to promptly detect whether the waveforms of the AC power supply unit 11 and / or the DC power supply unit 21 are abnormal, thereby being able to promptly detect whether the AC and DC are connected reversely, thereby facilitating timely control of the energy storage device to shut down, and avoiding damage to other components in the energy storage device, for example, damage to the switch power box 40, etc.

[0063] The first voltage detection unit 61 and the second voltage detection unit 62 can also be operational amplifiers. The operational amplifier can detect the voltage waveform and compare the voltage waveform with a preset reference waveform to determine whether the voltage waveform is abnormal, thereby outputting an alarm signal when an abnormal voltage waveform is detected. For example, when the first voltage detection unit 61 detects an abnormal voltage waveform, it outputs a first alarm signal, and when the second voltage detection unit 62 detects an abnormal voltage waveform, it outputs a second alarm signal. The voltage waveform can be the voltage waveform output by the DC power supply unit 21 detected by the operational amplifier, or it can be the voltage waveform output by the AC power supply unit 11. When the reference waveform corresponding to the first voltage detection unit 61 can be a sine wave, the reference waveform corresponding to the second voltage detection unit 62 can be a waveform corresponding to the DC voltage. In this embodiment, the operational amplifier detects the voltage waveform, and then detects whether the energy storage device has reversed AC and DC connections, thereby achieving low-cost detection of whether the energy storage device has reversed AC and DC connections.

[0064] For a better understanding of this embodiment, please refer to Figure 5 , Figure 5This is a brief circuit connection diagram of an example of this embodiment, in which the output ends of the AC power supply unit 11 are all connected to the rectifier bridge 121, the rectifier bridge 121 is also connected to the anode of the first anti-reverse diode 122, the cathode of the first anti-reverse diode 122 is connected to the first end of the bus capacitor 30, and the second end of the bus capacitor 30 is connected to the rectifier bridge 121. The control unit 63 is connected to the first voltage detection unit 61 and the second voltage detection unit 62. The first voltage detection unit 61 is connected to both ends of the AC power supply unit 11, and the second voltage detection unit 62 is connected to both ends of the DC power supply unit 21. The positive electrode of the DC power supply unit 21 is connected to the anode of the second anti-reverse diode 22, and the cathode of the second anti-reverse diode 22 is connected to the first end of the bus capacitor 30. The first and second ends of the bus capacitor 30 are both connected to the switching power supply box 40, and the second end of the bus capacitor 30 is connected to the negative electrode of the DC power supply unit 21. The switching power supply box 40 is connected to the PCS energy storage control module 50. The switching power supply box 40 can send electrical signals to the PCS energy storage control module 50, and the PCS energy storage control module 50 can also send electrical signals to the switching power supply box 40. In this embodiment, the control unit 63 can also be connected to the PCS energy storage control module 50. The control unit 63 can send the first alarm signal output by the first voltage detection unit 61 and the second alarm signal output by the second voltage detection unit 62 to the PCS energy storage control module 50, so that the energy storage device can be shut down by the PCS energy storage control module 50. This embodiment can detect whether the energy storage device has reversed AC and DC connections, thereby facilitating timely shutdown of the energy storage device when reversed AC and DC connections exist.

[0065] In addition, an embodiment of the present application further provides an energy storage system, which includes the energy storage device provided in the above embodiment.

[0066] Since the energy storage system proposed in this embodiment includes the energy storage device proposed in the above embodiments, it has the beneficial effects of the above embodiments. The specific working process and principle of the energy storage device are detailed in the energy storage devices provided in the above embodiments, which will not be described here one by one, and are all within the protection scope of this embodiment.

[0067] The above are only preferred embodiments of the present application and do not limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent processing scope of the present application.

Claims

1. An energy storage device, characterized in that: The energy storage device includes an AC module, a DC module, a bus capacitor, a switching power supply box and a PCS energy storage control module, and the AC module includes an AC power supply unit and a rectifier unit; The AC power supply unit is connected to the rectifier unit, the rectifier unit and the DC module are both connected to the bus capacitor, the bus capacitor is connected to the switch power box, and the switch power box is connected to the PCS energy storage control module; The rectifier unit is used to convert the AC voltage output by the AC power supply unit into a DC voltage, and the bus capacitor is used to filter the DC voltage.

2. The energy storage device according to claim 1, wherein The rectifier unit includes a rectifier bridge and a first anti-reverse diode; The AC power supply unit is connected to the rectifier bridge, the rectifier bridge is connected to the anode of the first anti-reverse diode, and the cathode of the first anti-reverse diode is connected to the bus capacitor.

3. The energy storage device according to claim 1, wherein The DC module includes a DC power supply unit and a second anti-reverse diode, the DC power supply unit is connected to the anode of the second anti-reverse diode, and the cathode of the second anti-reverse diode is connected to the bus capacitor.

4. The energy storage device according to claim 3, characterized in that In a case where the voltage output by the DC power supply unit is an AC voltage, the second anti-reverse diode performs half-wave rectification on the AC voltage to convert the AC voltage into a DC voltage.

5. The energy storage device according to claim 1, wherein The energy storage device further includes a voltage detection module, which is connected to the DC module and the AC module respectively.

6. The energy storage device according to claim 1, characterized in that The voltage detection module includes a first voltage detection unit, a second voltage detection unit, and a control unit, the control unit being connected to the first voltage detection unit and the second voltage detection unit respectively, the first voltage detection unit being connected to the DC power supply unit in the DC module, and the second voltage detection unit being connected to the AC power supply unit in the AC module; The first voltage detection unit is used to detect the voltage of the DC power supply unit, and the second voltage detection unit is used to detect the voltage of the AC power supply unit.

7. The energy storage device according to claim 6, characterized in that When it is detected that the voltage output by the DC power supply unit is an AC voltage, the first voltage detection unit sends a first alarm signal to the control unit to prompt that the voltage of the DC power supply unit is abnormal.

8. The energy storage device according to claim 6, wherein: In the case where it is detected that the voltage output by the AC power supply unit is a DC voltage, the second voltage detection unit sends a second alarm signal to the control unit to prompt that the voltage of the AC power supply unit is abnormal.

9. The energy storage device according to any one of claims 6 to 8, characterized in that: The first voltage detection unit and the second voltage detection unit are operational amplifiers.

10. An energy storage system, characterized in that: The energy storage system includes the energy storage device according to any one of claims 1 to 9.

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