Black start control method, energy storage device and energy storage system

Abstract

The embodiment of the invention provides a black-start control method, an energy storage device and an energy storage system. The performance of the energy storage system can be effectively improved. The black-start control method is applied to the energy storage system, the energy storage system comprises an energy storage device, the energy storage device comprises a plurality of battery clusters, a first controller and a black-start on-off device, and the black-start on-off device is arranged between a target battery cluster in the battery clusters and the first end of the first controller. The method comprises the steps that in response to a black start demand of the energy storage system, the first controller performs black start on the energy storage system based on the target battery cluster, and the black start on-off device is in a closed state; and after the black start, the first controller controls the black start on-off device to be switched from a closed state to an off state.

Description

Technical Field

[0001] This application relates to the technical field of energy storage, and particularly to a method for black start control, an energy storage device, and an energy storage system. Background Art

[0002] With the popularization and application of new energy, energy storage technology has also developed. During the operation of an energy storage system, problems such as power failure due to various faults may occur. At this time, the power supply of the entire energy storage system can be restored through black start. Black start refers to the situation where after the energy storage system loses power due to a fault, the entire energy storage system is in a "complete blackout" state of total power failure. At this time, without relying on an external power source, the power supply of the entire energy storage system is realized through the power of the battery device in the energy storage system.

[0003] After black start, how to improve the performance of the energy storage system is an urgent problem to be solved. Summary of the Invention

[0004] Embodiments of this application provide a method for black start control, an energy storage device, and an energy storage system, which can effectively improve the performance of the energy storage system.

[0005] In a first aspect, a method for black start control is provided, which is applied to an energy storage system. The energy storage system includes an energy storage device. The energy storage device includes a plurality of battery clusters, a first controller, and a black start on-off device. The black start on-off device is disposed between a target battery cluster among the plurality of battery clusters and a first end of the first controller. The method includes: in response to a black start requirement of the energy storage system, the first controller performs black start on the energy storage system based on the target battery cluster, where the black start on-off device is in a closed state; after black start, the first controller controls the black start on-off device to switch from the closed state to an off state.

[0006] In the embodiments of this application, by setting a black start on-off device in the energy storage device, after the energy storage system loses power, in response to the black start requirement of the energy storage system, the black start on-off device closes. In this way, the first controller can perform black start on the energy storage system in a timely manner based on the power of the target battery cluster, reducing the possibility of loss of key information and data in the energy storage system due to power failure of the energy storage system. In addition, after black start, the black start on-off device switches to the off state. In this way, the target battery cluster no longer supplies power to the first controller, not only reducing the power difference between the target battery cluster and other battery clusters in the energy storage device, but also reducing the possibility of overuse of the target battery cluster by the first controller, thereby effectively improving the performance of the energy storage device.

[0007] In some possible implementation manners, the energy storage device further includes a second target controller, which corresponds to the target battery cluster, and the second target controller is disposed between the target battery cluster and the black start switch device; the first controller controls the black start switch device to switch from a closed state to an off state, including: the first controller sends a switching message to the second target controller, and the switching message is used to indicate that the black start switch device is switched from a closed state to an off state.

[0008] Since the power consumption of the first controller is relatively large under normal circumstances, in this technical solution, the first controller sends a switching message to the second target controller for indicating that the state of the black start switch device is switched to an off state, and then the second target controller can switch the black start switch device from a closed state to an off state, which can reduce the power consumption of the energy storage device. In addition, the applicability of the embodiments of the present application can be increased. For example, the embodiments of the present application can be applied to scenarios where the first controller needs to be detected.

[0009] In some possible implementation manners, the energy storage device further includes a voltage conversion device, and two ends of the voltage conversion device are respectively connected to a second end of the first controller and a power supply, and are used to convert an output voltage output by the power supply into a required voltage of the first controller; the first controller controls the black start switch device to switch from a closed state to an off state, including: the first controller controls the black start switch device to switch from a closed state to an off state according to the state information of the voltage conversion device.

[0010] In this technical solution, by disposing a voltage conversion device between the first controller and the power supply, the voltage output by the power supply can be converted into the voltage required by the first controller, reducing the possibility that the first controller is damaged due to the too high voltage output by the power supply end, and ensuring the normal operation of the energy storage device.

[0011] In some possible implementation manners, the state information includes a power supply state and a fault state of the voltage conversion device, and the first controller controls the black start switch device to switch from a closed state to an off state according to the state information of the voltage conversion device, including: when the voltage conversion device does not have a fault and is in a power supply state, the first controller controls the black start switch device to switch from a closed state to an off state.

[0012] In this technical solution, the voltage conversion device is not faulty and is in the power supply state, indicating that the power supply can supply power to the first controller through the voltage conversion device. Therefore, the first controller controls the black start switch device to switch from the closed state to the off state, reducing the possibility that the first controller cannot work properly due to the off state of the black start switch device, and thus ensuring the normal operation of the energy storage system.

[0013] In some possible implementation manners, the voltage conversion device includes a first voltage conversion device and / or a second voltage conversion device. Two ends of the first voltage conversion device are respectively connected to a second end of the first controller and a bus of the energy storage device, and two ends of the second voltage conversion device are respectively connected to the second end of the first controller and a power supply end outside the energy storage device; in the case that the voltage conversion device is not faulty and is in the power supply state, controlling the black start switch device to switch from the closed state to the off state includes: when the first voltage conversion device is not faulty and is in the power supply state, and / or when the second voltage conversion device is not faulty and is in the power supply state, the first controller controls the black start switch device to switch from the closed state to the off state.

[0014] In the above technical solution, the voltage conversion device is set to include a first voltage conversion device or a second voltage conversion device, which not only reduces the space of the energy storage device occupied by the voltage conversion device, but also reduces the cost of the voltage conversion device. In addition, the voltage conversion device is set to include a first voltage conversion device and a second voltage conversion device, and the power supply ends of the first voltage conversion device and the second voltage conversion device are different, that is, multiple power sources are used to supply power to the first controller, so that if one of the power sources fails, the first controller can still work normally, improving the reliability of power supply.

[0015] In some possible implementation manners, the first voltage conversion device includes a plurality of first voltage conversion devices, and the plurality of first voltage conversion devices are connected in series, and / or the second voltage conversion device includes a plurality of second voltage conversion devices, and the plurality of second voltage conversion devices are connected in series; in the case that the first voltage conversion device is not faulty and is in the power supply state, and / or when the second voltage conversion device is not faulty and is in the power supply state, the first controller controls the black start switch device to switch from the closed state to the off state includes: when each first voltage conversion device in the plurality of first voltage conversion devices is not faulty and is in the power supply state, and / or when each second voltage conversion device in the plurality of second voltage conversion devices is not faulty and is in the power supply state, the first controller controls the black start switch device to switch from the closed state to the off state.

[0016] In the above technical solution, the first voltage conversion device includes a plurality of first voltage conversion devices, and / or the second voltage conversion device includes a plurality of second voltage conversion devices. In this way, the plurality of first voltage conversion devices can convert the high voltage output by the power supply into the low voltage required by the first controller, and / or the plurality of second voltage conversion devices can convert the high voltage output by the power supply into the low voltage required by the first controller, which not only reduces the loss of the first voltage conversion device and / or the loss of the second voltage conversion device, but also facilitates the selection of the first voltage conversion device and / or the selection of the second voltage conversion device.

[0017] In some possible implementation manners, when the voltage conversion device includes the second voltage conversion device, the power supply end located outside the energy storage device includes the bus of other energy storage devices in the energy storage system except the energy storage device.

[0018] In this way, when the energy storage device where the first controller is located fails and cannot supply power to the first controller, the power supply end located outside the energy storage device can continue to supply power to the first controller, which is beneficial to the normal operation of the first controller.

[0019] In some possible implementation manners, when the voltage conversion device is not faulty and is in the power supply state, the first controller controls the black start switch device to switch from the closed state to the off state, including: when the voltage conversion device is not faulty and is in the power supply state, and the continuous duration is greater than a preset duration, the first controller controls the black start switch device to switch from the closed state to the off state.

[0020] In this technical solution, when controlling the black start switch device to switch from the closed state to the off state, multiple factors are considered, that is, in addition to the state information of the voltage conversion device, the continuous duration of the state is also considered, which reduces the possibility of misjudgment by the first controller, and further reduces the probability that the first controller cannot work due to no power supply after switching the black start switch device to the off state, and improves the robustness of the energy storage device.

[0021] In some possible implementation manners, the first controller performs black start on the energy storage system based on the target battery cluster, including: the first controller controls the high voltage on the plurality of battery clusters based on the target battery cluster; the method further includes: when at least one battery cluster in the plurality of battery clusters is online with high voltage, determining that the first voltage conversion device is in the power supply state.

[0022] In this technical solution, since multiple battery clusters are connected in parallel, at least one battery cluster being at high voltage indicates that all battery clusters are at high voltage and online. When all battery clusters are at high voltage and online, the bus of the energy storage device is energized. Since the first voltage conversion device is connected to the bus of the energy storage device, the first voltage conversion device is in a powered state. Therefore, determining whether the first voltage conversion device is in a powered state based on whether the battery cluster is at high voltage can improve the accuracy of the determination.

[0023] In a second aspect, an energy storage device is provided, which is applied to an energy storage system. The energy storage device includes multiple battery clusters, a first controller, and a black start on-off device. The black start on-off device is arranged between a target battery cluster among the multiple battery clusters and the first end of the first controller. Wherein, in response to the black start requirement of the energy storage system, the black start on-off device is in a closed state, so that the first controller performs black start on the energy storage device based on the target battery cluster; after the black start, the black start on-off device is in an off state.

[0024] In some possible implementation manners, the energy storage device further includes a second target controller, the second target controller corresponds to the target battery cluster, and the second target controller is arranged between the target battery cluster and the black start on-off device. When the black start on-off device is in a closed state, the target battery cluster supplies power to the second target controller; the first controller is further configured to send switching information to the second target controller, and the switching information is used to indicate switching the black start on-off device from a closed state to an off state.

[0025] In some possible implementation manners, the energy storage device further includes a voltage conversion device. Two ends of the voltage conversion device are respectively connected to the second end of the first controller and a power supply, and are configured to convert the output voltage output by the power supply into the required voltage of the first controller. After the black start of the energy storage device, the first controller receives power through the voltage conversion device; the first controller is specifically configured to control the black start on-off device to switch from a closed state to an off state according to the status information of the voltage conversion device.

[0026] In some possible implementation manners, the voltage conversion device includes a first voltage conversion device, and two ends of the first voltage conversion device are respectively connected to a second end of the first controller and a bus of the energy storage device; and / or the voltage conversion device includes a second voltage conversion device, and two ends of the second voltage conversion device are respectively connected to a second end of the first controller and a power supply end located outside the energy storage device; the first controller is specifically configured to control the black start switch device to switch from a closed state to an off state when the first voltage conversion device does not fail and is in a power supply state, and / or when the second voltage conversion device does not fail and is in a power supply state.

[0027] In some possible implementation manners, the first voltage conversion device includes a plurality of first voltage conversion devices, and the plurality of first voltage conversion devices are connected in series; and / or the second voltage conversion device includes a plurality of second voltage conversion devices, and the plurality of second voltage conversion devices are connected in series; the first controller is specifically configured to: control the black start switch device to switch from a closed state to an off state when each first voltage conversion device among the plurality of first voltage conversion devices does not fail and is in a power supply state, and / or when each second voltage conversion device among the plurality of second voltage conversion devices does not fail and is in a power supply state.

[0028] In some possible implementation manners, when the voltage conversion device includes a second voltage conversion device, the power supply end located outside the energy storage device includes a bus of other energy storage devices in the energy storage system except the energy storage device.

[0029] In a third aspect, an energy storage system is provided, including a plurality of the energy storage devices in the second aspect above. Description of the Drawings

[0030] Figure 1 A schematic diagram of an energy storage device according to an embodiment of the present application is shown.

[0031] Figure 2 A schematic flowchart of a method for black start control according to an embodiment of the present application is shown.

[0032] Figure 3 A schematic diagram of an energy storage device according to an embodiment of the present application is shown.

[0033] Figure 4 A schematic diagram of another energy storage device according to an embodiment of the present application is shown.

[0034] Figure 5 A schematic diagram of an energy storage system according to an embodiment of the present application is shown. Detailed Embodiments

[0035] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the following will clearly describe the technical solutions in the embodiments of this application with reference to the accompanying drawings in the embodiments of this application. Obviously, the described embodiments are some, but not all, of the embodiments of this application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in this application without creative efforts shall fall within the scope of protection of this application.

[0036] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by those of ordinary skill in the technical field to which this application belongs; the terms used in the description of this application are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" and any variations thereof in the description and claims of this application and the above drawings are intended to cover non-exclusive inclusion. The terms "first", "second", etc. in the description and claims of this application or the above drawings are used to distinguish different objects and are not used to describe a specific order or primary-secondary relationship.

[0037] The directional terms appearing in the following description are all the directions shown in the figures and do not limit the specific structure of this application. In the description of this application, it should also be noted that unless otherwise clearly specified and limited, the terms "installed", "connected", and "coupled" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected or indirectly connected through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0038] Referring to "embodiment" in this application means that the specific features, structures, or characteristics described in connection with the embodiment can be included in at least one embodiment of this application. The phrase appears in various positions in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments. Those skilled in the art explicitly and implicitly understand that the embodiments described in this application can be combined with other embodiments.

[0039] The term "a plurality of" as used in this application means two or more (including two). Similarly, "a plurality of groups" means two or more groups (including two groups), and "a plurality of pieces" means two or more pieces (including two pieces).

[0040] With the popularization and application of new energy, energy storage technology has developed accordingly. An energy storage system is a device or system that can store energy and release it when needed. In the field of new energy, an energy storage system usually refers to a device that can store electrical energy and release electricity during peak electricity consumption periods. Energy storage systems play multiple roles in the power system, including load balancing, frequency regulation, backup power, peak-valley electricity price management, and improving grid stability. With the rapid development of renewable energy, the importance of energy storage systems is increasing day by day.

[0041] Electrochemical energy storage represented by lithium-ion batteries is the energy storage technology with the highest proportion. An electrochemical energy storage system consists of a battery device, a battery management system (BMS), an energy management system (EMS), a power conversion system (PCS), and auxiliary equipment.

[0042] Among them, the battery device can be, for example, a battery, a battery pack, etc. The battery device is the energy storage medium in the energy storage system and is responsible for storing and releasing electrical energy. The BMS is used to monitor and manage the state of the battery device, including the charge state, voltage, temperature, and current, etc., to ensure that the battery device operates within a safe range, prevent overcharging, over-discharging, overheating, and short circuits, thereby extending the life of the battery device. The EMS is the control center of the energy storage system and is responsible for monitoring the operating state of the entire system, optimizing the energy storage and release strategies to meet grid requirements or user-set goals. The PCS is mainly used to control the conversion and flow of electrical energy in the energy storage system, that is, to convert the direct current in the energy storage system into alternating current to meet the needs of the grid or load. At the same time, the PCS can also convert alternating current into direct current to charge the battery device in the energy storage system.

[0043] During the operation of the energy storage system, problems such as power loss due to various faults may occur. At this time, the power supply of the entire energy storage system can be restored through black start. Black start refers to the situation where, after the energy storage system loses power due to a fault, without relying on the help of other networks, through the start of the units with self-starting capabilities in the energy storage system, driving the units without self-starting capabilities, gradually expanding the recovery range of the energy storage system, and finally realizing the recovery of the entire energy storage system.

[0044] For example, the black start of the energy storage system can be achieved through the battery charge of the battery device in the energy storage system. After black start, if the battery device continues to supply power, an imbalance problem may occur between this battery device and other battery devices in the energy storage system, thereby affecting the performance of the energy storage system.

[0045] In view of this, an embodiment of the present application provides a method for black start control. This method is applied to an energy storage system, which includes an energy storage device. The energy storage device includes a plurality of battery clusters, a first controller, and a black start switch device. The black start switch device is disposed between a target battery cluster among the plurality of battery clusters and the first end of the first controller. The method includes: in response to a black start demand of the energy storage system, the first controller performs a black start on the energy storage device based on the target battery cluster, where the black start switch device is in a closed state. After the black start, the first controller controls the black start switch device to switch from the closed state to the off state. With this technical solution, by providing a black start switch device in the energy storage device, after the energy storage system loses power, in response to the black start demand of the energy storage system, the black start switch device closes. In this way, the first controller can perform a black start on the energy storage system in a timely manner based on the power of the target battery cluster, reducing the possibility of loss of key information and data in the energy storage system due to power loss of the energy storage system. In addition, after the black start, the black start switch device switches to the off state. In this way, the target battery cluster no longer supplies power to the first controller, not only reducing the power difference between the target battery cluster and other battery clusters in the energy storage device, but also reducing the possibility of overuse of the target battery cluster by the first controller, thereby effectively improving the performance of the energy storage device.

[0046] The technical solution of the embodiment of the present application can be applied to an energy storage system, which includes an energy storage device. The energy storage device can be used in an energy storage power station, a wind power generation system, a solar power generation system, a mobile power system, or a temporary power supply system, etc. The energy storage device can store electrical energy as needed and output electrical energy at an appropriate time. For example, the energy storage device can store electrical energy during a low electricity consumption period and provide electrical energy to relevant users or electrical equipment during a high electricity consumption period. The energy storage system provided by the embodiment of the present application can be any power system that requires an energy storage device. The energy storage device can be an energy storage device of various types and various sizes. Exemplarily, the energy storage device can be Figure 1 the energy storage container shown. The energy storage device can be, for example, a regular cuboid structure, where the six faces of the cuboid are the six outer walls of the energy storage device. Setting the energy storage device as a cuboid structure facilitates the fixed placement and transportation of the energy storage device. Of course, the energy storage device can also be of other shapes. For example, at least one wall of the energy storage device is inclined.

[0047] Figure 2 FIG. 200 shows a schematic flowchart of a method 200 for black start control according to an embodiment of the present application.

[0048] Among them, the method 200 can be applied to an energy storage system, which includes an energy storage device. As Figure 3As shown, the energy storage device includes a plurality of battery clusters, a first controller, and a black start switch-off device, and the black start switch-off device is disposed between a target battery cluster among the plurality of battery clusters and the first end of the first controller.

[0049] Method 200 may include at least some of the following.

[0050] S210: In response to a black start requirement of the energy storage system, the first controller performs a black start on the energy storage system based on the target battery cluster, where the black start switch-off device is in a closed state.

[0051] S220: After the black start, the first controller controls the black start switch-off device to switch from the closed state to the off state.

[0052] In the embodiment of the present application, by providing a black start switch-off device in the energy storage device, after the energy storage system loses power, in response to a black start requirement of the energy storage system, the black start switch-off device closes. In this way, the first controller can timely perform a black start on the energy storage system based on the power of the target battery cluster, reducing the possibility of loss of key information and data in the energy storage system due to power loss of the energy storage system. In addition, after the black start, the black start switch-off device switches to the off state. In this way, the target battery cluster no longer supplies power to the first controller, not only reducing the power difference between the target battery cluster and other battery clusters in the energy storage device, but also reducing the possibility of overuse of the target battery cluster by the first controller, thereby effectively improving the performance of the energy storage device.

[0053] Among them, the first controller may be, for example, a master battery management unit (MBMU), or may also be referred to as a Battery Management Controller (BMC) or other names. A plurality of battery clusters may correspond to one first controller.

[0054] The black start switch-off device may be, for example, a relay, a fuse, a switch, etc. In the case where the black start switch-off device is a relay, the relay may be, for example, a normally closed relay. The normally closed relay has a simple structure and stable operation, thereby improving the reliability of the energy storage device. In addition, the normally closed relay can be applied to a variety of control scenarios, thereby improving the flexibility of the energy storage device.

[0055] The target battery cluster may be at least one battery cluster among the plurality of battery clusters. As Figure 3 shown, the energy storage device includes n battery clusters, namely battery cluster 1, battery cluster 2... battery cluster n, and the target battery cluster is battery cluster n among the n battery clusters.

[0056] The first controller performs black start on the energy storage system based on the target battery cluster, which may include: the first controller performs black start on the energy storage system based on the power of the target battery cluster.

[0057] Specifically, when the energy storage system experiences a power outage, in response to the black start requirement of the energy storage system, the black start switch device closes, and then the target battery cluster supplies power to the first controller. After the first controller is powered on, the first controller can control the high voltage on multiple battery clusters. After the high voltage is applied to multiple battery clusters, the bus of the energy storage device is powered on, that is, the energy storage device is powered on. Since the PCS is connected to the energy storage device, the PCS is powered on. After the PCS is powered on, the PCS can convert direct current into alternating current, enabling the entire energy storage system to operate, thus achieving black start.

[0058] S220 may specifically include: the first controller directly controls the black start switch device to switch from the closed state to the off state.

[0059] Alternatively, the user can send an instruction to the first controller through the background, and this instruction is used to indicate switching the black start controller from the closed state to the off state. After receiving this instruction, the first controller can switch the black start switch device from the closed state to the off state.

[0060] Or, as Figure 4 shown, the energy storage device may further include a second controller. The second controller includes a target controller. The second target controller corresponds to the target battery cluster and is disposed between the target battery cluster and the black start switch device.

[0061] At this time, the first controller can send a switching message to the second controller, and this switching message is used to indicate switching the black start switch device from the closed state to the off state. In response to this switching message, the second controller can switch the black start switch device from the closed state to the off state.

[0062] Since the power consumption of the first controller is usually large, in this technical solution, the first controller sends a switching message to the second target controller for indicating switching the state of the black start switch device to the off state, and then the second target controller can switch the black start switch device from the closed state to the off state, which can reduce the power consumption of the energy storage device. In addition, the applicability of the embodiments of the present application can be increased. For example, the embodiments of the present application can be applied to scenarios where the first controller needs to be detected.

[0063] The second controllers correspond to the battery clusters one by one, that is, one battery cluster corresponds to one second controller. The second controller can be, for example, a slave battery management unit (SBMU). The second target controller is the controller among the second controllers that is connected to the target battery cluster.

[0064] The second target controller can, for example, draw power from the inside of the target battery cluster. In the case of a power failure in the energy storage system, the target battery cluster can supply power to the second target controller.

[0065] Alternatively, the second target controller can independently control the black start switch-off device to switch from the closed state to the off state.

[0066] It should be understood that after there is another power supply to supply power to the first controller, the first controller can switch the black start switch-off device from the closed state to the closed state.

[0067] The other power supply can be directly connected to the first controller to directly supply power to the first controller.

[0068] In some cases, the voltage of the other power supply may be relatively high, such as up to several thousand volts, while the required voltage of the first controller is usually relatively low. If the voltage of the other power supply is directly input to the first controller, it may damage the first controller.

[0069] Therefore, in some embodiments, the energy storage device may further include a voltage conversion device. The two ends of the voltage conversion device are respectively connected to the second end of the first controller and the power supply, and are used to convert the output voltage of the power supply into the required voltage of the first controller. At this time, the first controller can control the black start switch-off device to switch from the closed state to the off state according to the status information of the voltage conversion device.

[0070] In this technical solution, by setting a voltage conversion device between the first controller and the power supply, the voltage output by the power supply can be converted into the voltage required by the first controller, reducing the possibility of damage to the first controller due to the too high voltage at the power supply end, and ensuring the normal operation of the energy storage device.

[0071] The power supply can be the bus of the energy storage device, other energy storage devices in the energy storage system, or other power sources outside the energy storage system, etc. The other power source can be, for example, a fire protection device in the power grid.

[0072] Optionally, the voltage conversion device can include, but is not limited to, a direct current-direct current (DC-DC) converter.

[0073] When the power supply is the bus of the energy storage device, the output voltage may be thousands of volts, for example, 1500 volts (V), and the required voltage of the first controller may be several volts or dozens of volts. For example, it may be 5V - 50V, such as 9V, 15V, 20V, 30V, 36V, 40V, etc.

[0074] In some embodiments, the status information may include the power supply status and the fault status of the voltage conversion device. The power supply status indicates whether the voltage conversion device is in the power supply state, and the fault status indicates whether the voltage conversion device has a fault.

[0075] When the voltage conversion device has no fault and is in the power supply state, the first controller can control the black start switch device to switch from the closed state to the off state.

[0076] In this technical solution, the voltage conversion device has no fault and is in the power supply state, indicating that the power supply can supply power to the first controller through the voltage conversion device. Therefore, the first controller controls the black start switch device to switch from the closed state to the off state, reducing the possibility that the first controller cannot work properly due to the black start switch device being turned off, and thus ensuring the normal operation of the energy storage system.

[0077] The voltage conversion device may include a first voltage conversion device, and both ends of the first voltage conversion device are respectively connected to the second end of the first controller and the bus of the energy storage device. At this time, when the first voltage conversion device has no fault and is in the power supply state, the first controller can control the black start switch device to switch from the closed state to the off state.

[0078] Alternatively, the voltage conversion device may include a second voltage conversion device, and both ends of the second voltage conversion device are respectively connected to the second end of the first controller and a power supply terminal located outside the energy storage device. At this time, when the second voltage conversion device has no fault and is in the power supply state, the first controller can control the black start switch device to switch from the closed state to the off state.

[0079] In the above technical solution, the voltage conversion device is set to include the first voltage conversion device or the second voltage conversion device, which not only reduces the space of the energy storage device occupied by the voltage conversion device, but also reduces the cost of the voltage conversion device.

[0080] Among them, the power supply terminal located outside the energy storage device may, for example, include the bus of other energy storage devices in the energy storage system, or other power sources located outside the energy storage system, etc. In this way, when the energy storage device where the first controller is located fails and cannot supply power to the first controller, the power supply terminal located outside the energy storage device can continue to supply power to the first controller, which is beneficial to the normal operation of the first controller.

[0081] Alternatively, the voltage conversion device may include a first voltage conversion device and a second voltage conversion device. In this case, when the first voltage conversion device is not faulty and is in the power supply state, or when the second voltage conversion device is not faulty and is in the power supply state, the first controller may control the black start on-off device to switch from the closed state to the off state.

[0082] In the above technical solution, the voltage conversion device is set to include a first voltage conversion device and a second voltage conversion device, and the power supply ends of the first voltage conversion device and the second voltage conversion device are different, that is, multiple power supplies are used to supply power to the first controller, so that if one of the power supplies has an abnormality, the first controller can still work normally, improving the reliability of power supply.

[0083] Optionally, when the first voltage conversion device is not faulty and is in the power supply state, and the second voltage conversion device is also not faulty and is in the power supply state, the first controller may receive the power output by the first voltage conversion device, or the first controller may receive the power output by the second voltage conversion device, or the first controller may receive the power output by the first voltage conversion device and the second voltage conversion device at the same time.

[0084] Of course, in addition to the first voltage conversion device and the second voltage conversion device, the voltage conversion device may further include other voltage conversion devices, that is, the embodiments of the present application may use more power supplies to supply power to the first controller.

[0085] When one end of the first voltage conversion device is connected to the bus of the energy storage device, after the battery cluster is under high voltage, the bus of the energy storage device will be energized, so as to supply power to the first controller. Therefore, the power supply state of the voltage conversion device can be determined by judging whether the battery cluster is under high voltage.

[0086] Specifically, the first controller may control multiple battery clusters to be under high voltage based on the power of the target battery cluster. When at least one of the multiple battery clusters is under high voltage, the first controller may determine that the first voltage conversion device is in the power supply state.

[0087] In this technical solution, since the multiple battery clusters are connected in parallel, at least one battery cluster being under high voltage indicates that all the battery clusters are under high voltage and online. When all the battery clusters are under high voltage and online, the bus of the energy storage device is energized. Since the first voltage conversion device is connected to the bus of the energy storage device, the first voltage conversion device is in the power supply state. Therefore, determining whether the first voltage conversion device is in the power supply state according to whether the battery cluster is under high voltage can improve the accuracy of judgment.

[0088] The first voltage conversion device may include one first voltage conversion device.

[0089] Alternatively, considering that the bus voltage of the energy storage device is usually relatively high, up to thousands of volts, while the voltage required by the first controller may be dozens of volts. If the first voltage conversion device includes only one first voltage conversion device, the first voltage conversion device needs to convert the voltage of thousands of volts into dozens of volts. Thus, the requirements for the first voltage conversion device are relatively high.

[0090] Therefore, the first voltage conversion device may include multiple first voltage conversion devices, which are connected in series. At this time, when each of the multiple first voltage conversion devices does not fail and is in a powered state, the first voltage conversion device can supply power to the first controller.

[0091] For example, the first voltage conversion device includes two first voltage conversion devices. The bus voltage of the energy storage device is 1500V, and the voltage required by the first controller is 24V. The first voltage conversion device connected to the bus of the energy storage device is used to convert 1500V into 220V, and the first voltage conversion device connected to the first controller is used to convert 220V into 24V.

[0092] The second voltage conversion device may include one second voltage conversion device.

[0093] Alternatively, similar to the first voltage conversion device, the second voltage conversion device may include multiple second voltage conversion devices, which are connected in series. At this time, when each of the multiple second voltage conversion devices does not fail and is in a powered state, the second voltage conversion device can supply power to the first controller.

[0094] In the above technical solution, the first voltage conversion device includes multiple first voltage conversion devices, and / or the second voltage conversion device includes multiple second voltage conversion devices. In this way, the multiple first voltage conversion devices can convert the high voltage output by the power supply into the low voltage required by the first controller, and / or the multiple second voltage conversion devices can convert the high voltage output by the power supply into the low voltage required by the first controller. This not only reduces the loss of the first voltage conversion device and / or the second voltage conversion device, but also facilitates the selection of the first voltage conversion device and / or the second voltage conversion device.

[0095] Figure 5 Fig. shows a schematic diagram of an energy storage system. As Figure 5As shown in the figure, the energy storage system includes an energy storage device 1 and an energy storage device 2. The energy storage device 1 is the energy storage device of the embodiment of the present application, and the energy storage device 2 is other energy storage devices. The first voltage conversion device includes two first voltage conversion devices, namely the first voltage conversion device 1 and the first voltage conversion device 2. The first voltage conversion device 1 is respectively connected to the bus of the energy storage device and the first voltage conversion device 2, and the other end of the first voltage conversion device 2 is connected to the first controller. The second voltage conversion device includes two second voltage conversion devices, namely the second voltage conversion device 1 and the second voltage conversion device 2. The second voltage conversion device 1 is respectively connected to the bus of the other energy storage device and the second voltage conversion device 2, and the other end of the second voltage conversion device 2 is connected to the first controller.

[0096] Further, in addition to the status information of the voltage conversion device, the first controller can also control the black start switch device to switch from the closed state to the off state according to other parameters.

[0097] As an example, in some cases, the voltage conversion device is not faulty and is in the power supply state, which may be only for an instant. At other times, the voltage conversion device may not be in the power supply state or may be faulty. Or, the first controller may make a wrong judgment, and the voltage conversion device may be faulty or not in the power supply state. In this case, if the black start switch device is controlled to switch from the closed state to the off state, there may be a problem that the first controller has no power supply and cannot work.

[0098] Therefore, the other parameters can include the duration of the voltage conversion device status. In other words, when the voltage conversion device is not faulty and is in the power supply state, the first controller controls the black start switch device to switch from the closed state to the off state, which can include: when the voltage conversion device is not faulty and is in the power supply state, and the duration of the state that the voltage conversion device is not faulty and is in the power supply state is greater than the preset duration, the first controller controls the black start switch device to switch from the closed state to the off state.

[0099] This technical solution considers multiple factors when controlling the black start switch device to switch from the closed state to the off state, that is, in addition to the status information of the voltage conversion device, it also considers the duration of the state, reducing the possibility of misjudgment by the first controller, and further reducing the probability that the first controller cannot work due to no power supply after switching the black start switch device to the off state, improving the robustness of the energy storage device.

[0100] The preset duration can be, for example, 5 seconds (s), 10 s, 20 s, 30 s, etc.

[0101] In the embodiments of the present application, the magnitudes of the sequence numbers of the above processes do not mean the order of execution. The order of execution of each process should be determined according to its function and internal logic, and should not constitute any limitation to the implementation process of the embodiments of the present application.

[0102] Moreover, on the premise of no conflict, each embodiment described in the present application and / or the technical features in each embodiment can be combined arbitrarily, and the technical solutions obtained after combination should also fall within the protection scope of the present application.

[0103] The method for black start control in the embodiments of the present application has been described in detail above. Next, the energy storage device in the embodiments of the present application will be described. It should be understood that the method for black start control in the embodiments of the present application can be applied to the energy storage device in the embodiments of the present application.

[0104] As Figure 3 shown, the energy storage device includes a plurality of battery clusters, a first controller, and a black start switch-off device. The black start switch-off device is disposed between a target battery cluster among the plurality of battery clusters and the first end of the first controller. Wherein, in response to the black start demand of the energy storage system, the black start switch-off device is in a closed state, so that the first controller performs black start on the energy storage device based on the target battery cluster. After the black start, the black start switch-off device is in an off state.

[0105] Optionally, in the embodiments of the present application, the energy storage device further includes a second target controller. The second target controller corresponds to the target battery cluster, and the second target controller is disposed between the target battery cluster and the black start switch-off device. When the black start switch-off device is in a closed state, the target battery cluster supplies power to the second target controller. The first controller is further configured to send switching information to the second target controller, and the switching information is used to instruct to switch the black start switch-off device from the closed state to the off state.

[0106] Optionally, in the embodiments of the present application, the energy storage device further includes a voltage conversion device. Two ends of the voltage conversion device are respectively connected to the second end of the first controller and a power supply. The voltage conversion device is configured to convert the output voltage output by the power supply into the required voltage of the first controller. After the black start of the energy storage device, the first controller receives power through the voltage conversion device. The first controller is specifically configured to control the black start switch-off device to switch from the closed state to the off state according to the status information of the voltage conversion device.

[0107] Optionally, in the embodiments of the present application, the voltage conversion device includes a first voltage conversion device, and both ends of the first voltage conversion device are respectively connected to the second end of the first controller and the bus of the energy storage device; and / or the voltage conversion device includes a second voltage conversion device, and both ends of the second voltage conversion device are respectively connected to the second end of the first controller and a power supply terminal located outside the energy storage device; the first controller is specifically configured to control the black start switch device to switch from the closed state to the off state when the first voltage conversion device does not fail and is in the power supply state, and / or when the second voltage conversion device does not fail and is in the power supply state.

[0108] Optionally, in the embodiments of the present application, the first voltage conversion device includes a plurality of first voltage conversion devices, and the plurality of first voltage conversion devices are connected in series; and / or the second voltage conversion device includes a plurality of second voltage conversion devices, and the plurality of second voltage conversion devices are connected in series; the first controller is specifically configured to: control the black start switch device to switch from the closed state to the off state when each of the plurality of first voltage conversion devices does not fail and is in the power supply state, and / or when each of the plurality of second voltage conversion devices does not fail and is in the power supply state.

[0109] Optionally, in the embodiments of the present application, when the voltage conversion device includes a second voltage conversion device, the power supply terminal located outside the energy storage device includes the bus of other energy storage devices in the energy storage system except the energy storage device.

[0110] It should be understood that the energy storage device can implement the corresponding operations in the method 200 for black start control. For the sake of brevity, it will not be elaborated here.

[0111] The embodiments of the present application further provide an energy storage system. The energy storage system includes a plurality of energy storage devices. One of the plurality of energy storage devices can be, for example, Figure 3 the energy storage device in

[0112] Among them, two adjacent energy storage devices among the plurality of energy storage devices can be arranged in contact with each other, or there can also be a certain distance between two rows of energy storage devices.

[0113] As described above, the energy storage system may further include a PCS, and the PCS is used to connect between the power generation device and the energy storage device. The power generation device is used to generate electric energy, and the electric energy generated by the power generation device can be stored in the energy storage device through the PCS. As an example, the power generation device can specifically be a solar panel, a hydroelectric power generation device, a thermal power generation device, a wind power generation device, etc. Among them, the specific type of the power generation device is not limited in the present application.

[0114] Although the present application has been described with reference to preferred embodiments, various modifications can be made thereto and components thereof can be replaced with equivalents without departing from the scope of the present application. In particular, as long as there is no structural conflict, the technical features mentioned in each embodiment can be combined in any manner. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A black start control method, characterized in that: Applied to an energy storage system, the energy storage system includes an energy storage device, the energy storage device includes multiple battery clusters, a first controller and a black start on-off device, the black start on-off device is arranged between a target battery cluster among the multiple battery clusters and a first end of the first controller, the method includes: In response to a black start requirement of the energy storage system, the first controller performs a black start on the energy storage system based on the target battery cluster, wherein the black start switching device is in a closed state; After the black start, the first controller controls the black start on-off device to switch from a closed state to an off state.

2. The method according to claim 1, characterized in that The energy storage device further includes a second target controller, the second target controller corresponds to the target battery cluster, and the second target controller is arranged between the target battery cluster and the black start switching device; The first controller controls the black start on-off device to switch from a closed state to an off state, including: The first controller sends switching information to the second target controller, where the switching information is used to instruct to switch the black start switching device from a closed state to an off state.

3. The method according to claim 1 or 2, characterized in that: The energy storage device further includes a voltage conversion device, two ends of which are respectively connected to the second end of the first controller and the power supply, and are used to convert the output voltage output by the power supply into the required voltage of the first controller; The first controller controls the black start on-off device to switch from a closed state to an off state, including: The first controller controls the black start switching device to switch from a closed state to an off state according to the state information of the voltage conversion device.

4. The method according to claim 3, characterized in that The state information includes a power supply state and a fault state of the voltage conversion device, and the first controller controls the black start switching device to switch from a closed state to an off state according to the state information of the voltage conversion device, including: When the voltage conversion device does not fail and is in a power supply state, the first controller controls the black start switching device to switch from a closed state to an off state.

5. The method according to claim 4, characterized in that The voltage conversion device includes a first voltage conversion device and / or a second voltage conversion device, two ends of the first voltage conversion device are respectively connected to the second end of the first controller and the busbar of the energy storage device, and two ends of the second voltage conversion device are respectively connected to the second end of the first controller and a power supply end outside the energy storage device; When the voltage conversion device does not fail and is in a power supply state, controlling the black start switching device to switch from a closed state to an off state includes: When the first voltage conversion device does not fail and is in a power supply state, and / or when the second voltage conversion device does not fail and is in a power supply state, the first controller controls the black start switching device to switch from a closed state to an off state.

6. The method according to claim 5, characterized in that The first voltage conversion device includes a plurality of first voltage conversion devices, the plurality of first voltage conversion devices are connected in series, and / or the second voltage conversion device includes a plurality of second voltage conversion devices, the plurality of second voltage conversion devices are connected in series; When the first voltage conversion device does not fail and is in a power supply state, and / or when the second voltage conversion device does not fail and is in a power supply state, the first controller controls the black start switching device to switch from a closed state to an off state, including: When each of the multiple first voltage conversion devices has not failed and is in a power supply state, and / or when each of the multiple second voltage conversion devices has not failed and is in a power supply state, the first controller controls the black start switching device to switch from a closed state to an off state.

7. The method according to claim 5 or 6, characterized in that: In the case where the voltage conversion device includes a second voltage conversion device, the power supply end located outside the energy storage device includes bus bars of other energy storage devices in the energy storage system except the energy storage device.

8. The method according to any one of claims 4 to 7, characterized in that When the voltage conversion device does not fail and is in a power supply state, the first controller controls the black start switching device to switch from a closed state to an off state, including: When the voltage conversion device does not fail and is in a power supply state, and the duration is greater than a preset duration, the first controller controls the black start switching device to switch from a closed state to an off state.

9. The method according to any one of claims 5 to 7, characterized in that The first controller performs a black start on the energy storage system based on the target battery cluster, including: The first controller controls the high voltage on the plurality of battery clusters based on the target battery cluster; The method further comprises: When at least one of the plurality of battery clusters has a high voltage on-line, it is determined that the first voltage conversion device is in a power supply state.

10. An energy storage device, characterized in that: Applied to an energy storage system, the energy storage device comprises a plurality of battery clusters, a first controller and a black start on-off device, wherein the black start on-off device is arranged between a target battery cluster among the plurality of battery clusters and a first end of the first controller; Wherein, in response to a black start requirement of the energy storage system, the black start on-off device is in a closed state, so that the first controller performs a black start on the energy storage device based on the target battery cluster; After the black start, the black start switching device is in the off state.

11. The energy storage device according to claim 10, characterized in that: The energy storage device further includes a second target controller, which corresponds to the target battery cluster and is arranged between the target battery cluster and the black start switching device. When the black start switching device is in a closed state, the target battery cluster supplies power to the second target controller. The first controller is further used to send switching information to the second target controller, where the switching information is used to instruct to switch the black start switching device from a closed state to an off state.

12. The energy storage device according to claim 10 or 11, characterized in that: The energy storage device further includes a voltage conversion device, two ends of which are respectively connected to the second end of the first controller and the power supply, and are used to convert the output voltage of the power supply into a required voltage of the first controller. After the energy storage device is black-started, the first controller receives electric quantity through the voltage conversion device; The first controller is specifically used to control the black start switching device to switch from a closed state to an off state according to the state information of the voltage conversion device.

13. The energy storage device according to claim 12, characterized in that: The voltage conversion device comprises a first voltage conversion device, two ends of which are respectively connected to the second end of the first controller and the busbar of the energy storage device; and / or The voltage conversion device includes a second voltage conversion device, and two ends of the second voltage conversion device are respectively connected to the second end of the first controller and a power supply end located outside the energy storage device; The first controller is specifically used to control the black start switching device to switch from a closed state to an off state when the first voltage conversion device has not failed and is in a power supply state, and / or when the second voltage conversion device has not failed and is in a power supply state.

14. The energy storage device according to claim 13, characterized in that: The first voltage conversion device includes a plurality of first voltage conversion devices, and the plurality of first voltage conversion devices are connected in series; and / or The second voltage conversion device includes a plurality of second voltage conversion devices, and the plurality of second voltage conversion devices are connected in series; The first controller is specifically used for: When each of the multiple first voltage conversion devices has not failed and is in a power supply state, and / or when each of the multiple second voltage conversion devices has not failed and is in a power supply state, the black start switching device is controlled to switch from a closed state to an off state.

15. The energy storage device according to claim 13 or 14, characterized in that: In the case where the voltage conversion device includes a second voltage conversion device, the power supply end located outside the energy storage device includes bus bars of other energy storage devices in the energy storage system except the energy storage device.

16. An energy storage system, characterized in that: include: A plurality of energy storage devices according to any one of claims 10 to 15.

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