energy storage system

Abstract

The application relates to an energy storage system, comprising: an energy storage unit and a load power supply connected with a bidirectional conversion unit; the bidirectional conversion unit is used for controlling the energy storage unit to keep a discharging state in a power consumption mode until the voltage of the energy storage unit decreases to a safety voltage threshold. According to the application, the safety discharging management of the power consumption mode of the energy storage system is provided, the energy storage unit is controlled to discharge until the voltage decreases to the safety voltage threshold, and therefore the safety in the battery maintenance, replacement, recovery and storage process is guaranteed.

Description

Technical Field

[0001] This application relates to the field of energy storage management technology, and in particular to an energy storage system. Background Technology

[0002] Energy storage systems are technological devices capable of storing energy and releasing it when needed. They generally include energy storage units, bidirectional conversion units, and load power sources. The bidirectional conversion unit converts electrical energy between the energy storage units and the load power source, allowing the energy storage units to discharge to the load power source or the load power source to charge the energy storage units. However, current energy storage systems require power outages and manual discharge operations using additional discharge devices when maintenance, replacement, or recycling of the energy storage batteries is needed. This process is cumbersome, and the discharge process itself poses safety risks due to excessively fast or slow discharge, thus compromising the safety of battery maintenance, replacement, recycling, and storage.

[0003] There is currently no effective solution to the problem that the relevant technologies lack a plan to ensure the safety of battery maintenance, replacement, recycling, and storage. Utility Model Content

[0004] Therefore, it is necessary to provide an energy storage system that can achieve safe discharge in response to the above-mentioned technical problems.

[0005] In a first aspect, this embodiment provides an energy storage system, including: an energy storage unit connected to a bidirectional conversion unit and a load power supply;

[0006] The bidirectional conversion unit is used to control the energy storage unit to remain in a discharging state in the power consumption mode until the voltage of the energy storage unit drops to a safe voltage threshold.

[0007] In some embodiments, the energy storage system further includes:

[0008] A power management module is used to monitor the voltage of the energy storage unit;

[0009] The bidirectional conversion unit includes a memory, a processor, and a converter. The memory stores the safe voltage threshold. The processor is connected to the power management module, the memory, and the converter. The processor is used to receive the voltage of the energy storage unit in the power consumption mode and generate a PWM signal to drive the converter to adjust the voltage of the energy storage unit down to the safe voltage threshold.

[0010] In some embodiments, the memory also stores a preset discharge curve, and the processor is used to obtain the remaining power of the energy storage unit by using the voltage of the energy storage unit and the preset discharge curve.

[0011] In some embodiments, the memory also stores multiple levels of battery power, and the processor generates different PWM signal duty cycles when the remaining battery power is at different levels, so as to drive the converter to adjust the discharge power of the energy storage unit.

[0012] In some embodiments, the energy storage system further includes: an interaction module connected to the processor, the interaction module including an operating interface;

[0013] The user interface is equipped with function buttons for triggering the power consumption mode.

[0014] In some embodiments, the interaction module includes a display interface;

[0015] The display interface is used to display the status parameters of the energy storage unit, including power, voltage and current.

[0016] In some embodiments, the bidirectional conversion unit further includes a power supply module;

[0017] The power supply module is powered by the energy storage unit or the load power supply and is used to provide power to the energy storage system.

[0018] In some embodiments, an energy storage unit-side switch is connected between the power supply module and the energy storage unit, and a load power supply-side switch is connected between the power supply module and the load power supply. The energy storage unit includes a processor, which controls the disconnection of the energy storage unit-side switch and the closing of the load power supply-side switch when the voltage of the energy storage unit drops to the safe voltage threshold, thereby switching the load power supply to power the power supply module.

[0019] In some embodiments, an energy storage unit-side switch is connected between the power supply module and the energy storage unit, and a load power supply-side switch is connected between the power supply module and the load power supply. The energy storage unit includes a processor for controlling the closing of the energy storage unit-side switch and the opening of the load power supply-side switch in power consumption mode, thereby switching the energy storage unit to supply power to the power supply module.

[0020] In some embodiments, the energy storage system further includes a protection unit;

[0021] The protection unit includes a pre-charge resistor, a fuse, and a circuit breaker, used to disconnect the bidirectional conversion unit from the energy storage unit and / or the load power supply in the event of an abnormal current.

[0022] Compared with related technologies, the energy storage system provided in this embodiment includes: an energy storage unit connected to a bidirectional conversion unit and a load power supply; the bidirectional conversion unit is used to control the energy storage unit to maintain a discharge state in the power consumption mode until the voltage of the energy storage unit drops to a safe voltage threshold. This embodiment provides safe discharge management for the power consumption mode of the energy storage system, controlling the energy storage unit to discharge until the voltage drops to a safe voltage threshold, thereby ensuring the safety of battery maintenance, replacement, recycling, and storage processes.

[0023] Details of one or more embodiments of this application are set forth in the following drawings and description to make other features, objects and advantages of this application more readily apparent. Attached Figure Description

[0024] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, illustrate exemplary embodiments and are used to explain this application, but do not constitute an undue limitation of this application. In the drawings:

[0025] Figure 1 This is a schematic diagram of the energy storage system in one embodiment;

[0026] Figure 2 This is a schematic diagram of the energy storage system in another embodiment. Detailed Implementation

[0027] To better understand the purpose, technical solution, and advantages of this application, the application is described and illustrated below in conjunction with the accompanying drawings and embodiments.

[0028] Unless otherwise defined, the technical or scientific terms used in this application shall have the general meaning as understood by one of ordinary skill in the art to which this application pertains. Words such as “a,” “an,” “an,” “the,” “the,” and “these,” used in this application, do not indicate quantitative limitation and may be singular or plural. The terms “comprising,” “including,” “having,” and any variations thereof used in this application are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or device that comprises a series of steps or modules (units) is not limited to the listed steps or modules (units) but may include steps or modules (units) not listed, or may include other steps or modules (units) inherent to such processes, methods, products, or devices. The terms “connected,” “linked,” and “coupled,” used in this application, are not limited to physical or mechanical connections but may include electrical connections, whether direct or indirect. The term “multiple” used in this application refers to two or more. The "and / or" operator describes the relationship between related objects, indicating that three relationships can exist. For example, "A and / or B" can represent three cases: A alone, A and B simultaneously, and B alone. Typically, the character " / " indicates that the objects before and after it are in an "or" relationship. The terms "first," "second," and "third," etc., used in this application are merely for distinguishing similar objects and do not represent a specific ordering of the objects.

[0029] This embodiment provides a schematic diagram of an energy storage system, such as... Figure 1 As shown, the energy storage system includes: an energy storage unit connected to the bidirectional conversion unit and a load power supply;

[0030] The bidirectional conversion unit is used to control the energy storage unit to remain in a discharging state in the power consumption mode until the voltage of the energy storage unit drops to a safe voltage threshold.

[0031] The energy storage unit includes energy storage media such as capacitors or batteries. An energy storage system is a technical device that can store energy and release it when needed. The bidirectional conversion unit is used to convert the electrical energy between the energy storage unit and the load power source, so that the energy storage unit can discharge to the load power source or the load power source can charge the energy storage unit.

[0032] When maintenance of energy storage units is required, such as dismantling, replacement, or recycling, the energy storage unit's charge usually does not drop below the safe voltage because the battery charge can be high or low. This can lead to safety hazards such as excessively fast or slow discharge during maintenance, and the safety of storing and recycling energy storage units cannot be guaranteed.

[0033] Based on this, the energy storage system provides a power consumption mode for the energy storage unit. This mode is triggered when maintenance is required. In this mode, the processor in the bidirectional conversion unit controls the energy storage unit to remain in a discharging state, without charging, ensuring that the energy storage unit's charge is gradually depleted until its voltage drops to a safe voltage threshold. This provides a safe power consumption mode, facilitating the removal, replacement, or recycling of the energy storage unit. The safe voltage threshold can be preset and stored in the bidirectional conversion unit.

[0034] This embodiment provides a power consumption mode for the energy storage system to manage safe discharge, controlling the energy storage unit to discharge until the voltage drops to a safe voltage threshold, thereby ensuring the safety of battery maintenance, replacement, recycling, and storage.

[0035] In some embodiments, the energy storage system further includes: a power management module for monitoring the voltage of the energy storage unit; a bidirectional conversion unit including a memory, a processor, and a converter, wherein the memory stores a safe voltage threshold, the processor is connected to the power management module, the memory, and the converter respectively, and the processor is used to receive the voltage of the energy storage unit in a power consumption mode and generate a PWM signal to drive the converter to adjust the voltage of the energy storage unit down to the safe voltage threshold.

[0036] Specifically, the power management module uses a high-precision voltage detection circuit to monitor the voltage of the energy storage unit in real time. The processor in the bidirectional conversion unit receives the voltage of the energy storage unit monitored by the power management module and calculates the remaining charge (SOC) of the energy storage unit based on the voltage. It then performs safe discharge management and generates a PWM (Pulse Width Modulation) signal corresponding to the remaining charge. The PWM signal drives the converter to adjust the voltage of the energy storage unit down to the safe voltage threshold. This adjustment process is also applicable to the power consumption mode of the energy storage system.

[0037] Figure 2 This is a schematic diagram of the energy storage system in this embodiment, as shown below. Figure 2 As shown, the bidirectional conversion unit includes a memory (not shown), a processor, and a converter (not shown). The memory stores a safe voltage threshold, and the processor is connected to the power management module (not shown), the memory, and the converter. The converter can be a DC-DC converter, located in the DC-DC main circuit. The DC-DC main circuit also includes a complete power supply link for input filtering, output voltage regulation, protection circuits, and control logic.

[0038] In some embodiments, the memory also stores a preset discharge curve, and the processor is used to obtain the remaining power of the energy storage unit by using the voltage of the energy storage unit and the preset discharge curve.

[0039] Specifically, the preset discharge curve is an experimental curve showing the change in voltage with discharge capacity under specific conditions (temperature, discharge rate), serving as a benchmark reference for SOC estimation. Using the preset discharge curve as a reference, the processor can estimate the remaining capacity based on the voltage of the energy storage unit.

[0040] In some embodiments, the memory also stores multiple levels of battery power. When the remaining battery power is at different levels, the processor generates different PWM signal duty cycles to drive the converter to adjust the discharge power of the energy storage unit.

[0041] Specifically, different PWM signal duty cycles are generated for different power levels. By adjusting the duty cycle, the discharge power of the energy storage unit is adjusted, so that the voltage of the energy storage unit can be gradually, efficiently and safely reduced to the safe voltage threshold.

[0042] The following is a rule for adjusting PWM signals:

[0043] When the remaining charge (SOC) is greater than 70%, the PWM duty cycle is set to 80% to perform high-power discharge and quickly consume battery energy.

[0044] When the remaining charge (SOC) is between 30% and 70%, the PWM duty cycle is reduced to 50% to perform medium-power discharge, simulating the stable discharge phase.

[0045] When the remaining charge (SOC) is less than or equal to 30%, the PWM duty cycle is reduced to below 20% to perform low-power discharge, avoiding over-discharge that could damage the battery.

[0046] Taking an embedded system as an example, the PWM signal is generated by a timer module. The period of the timer determines the frequency of the PWM, which is usually set to about 60kHz. The duty cycle is changed by adjusting the count value of the timer. The processor controls the converter with PWM signals of different duty cycles to adjust the discharge power of the energy storage unit, ensuring that the battery energy is gradually, efficiently and safely depleted.

[0047] Furthermore, by learning from historical usage data of the energy storage unit (such as charge / discharge cycles, temperature changes, and SOC changes) through an embedded system, the system can predict the battery's discharge characteristics and trends in advance. During long-term battery use, historical data can be used for adaptive adjustments to improve battery discharge efficiency under different environments. For example, based on SOC change trends under different environments, the PWM regulation strategy can be optimized to achieve more efficient battery energy management.

[0048] The power level and duty cycle settings in the above adjustment rules are not specifically configured. For example, the number of power levels, the power value of each power level, and the duty cycle value can all be adjusted according to the actual application.

[0049] The discharge management of the energy storage unit provided in this embodiment can dynamically adjust the duty cycle of the PWM signal according to the SOC of the energy storage unit to adjust the discharge power and ensure that the voltage of the energy storage unit can be gradually, efficiently and safely reduced to the safe voltage threshold.

[0050] In some of these embodiments, such as Figure 2 As shown, the energy storage system also includes an interaction module connected to the processor, which includes an operating interface; the operating interface is equipped with function buttons for triggering power consumption modes.

[0051] The interaction module also includes a display interface; the display interface is used to display the status parameters of the energy storage unit, including power, voltage and current.

[0052] Specifically, the interactive module can be located in the energy storage control cabinet. The operating interface includes physical function buttons or virtual touch-sensitive function buttons; the specific configuration is not limited. When maintenance of the energy storage unit is required, personnel can trigger a power consumption mode via these function buttons. In this mode, the processor controls the closing of the energy storage unit's side switch and disconnects the load power supply side switch, switching the energy storage unit to supply power to the power supply module. The energy storage unit remains in a discharging state, without charging, ensuring that the energy storage unit's charge is gradually depleted. This provides a safe power consumption mode and guarantees safety during maintenance. Additionally, the interactive module includes a display interface that shows the energy storage unit's status parameters (voltage, current, charge, temperature, cycle count), allowing real-time monitoring of voltage and remaining current to ensure the safety of maintenance operations.

[0053] In some embodiments, the energy storage system further includes a protection unit; the protection unit includes a pre-charge resistor, a fuse, and a circuit breaker for disconnecting the bidirectional conversion unit from the energy storage unit and / or the load power supply in the event of an abnormal current.

[0054] In some of these embodiments, such as Figure 2 As shown, the bidirectional conversion unit also includes: a power supply module; the power supply module is powered by the energy storage unit or the load power supply and is used to provide power to the energy storage system.

[0055] Specifically, the energy storage unit and load power supply can provide a dual power supply design for the power supply module in the bidirectional conversion unit. The power supply module is used to provide power to the energy storage system, specifically to provide auxiliary power for the power conversion control work, specifically to provide low voltage (such as 3.3V, 5V, 12V) for control chips (such as PWM controllers, MCUs), drive chips, sensors, communication modules, etc.

[0056] The power supply module is connected to the energy storage unit side switch, and the power supply module is connected to the load power supply side switch. The energy storage unit includes a processor, which controls the disconnection of the energy storage unit side switch and the closing of the load power supply side switch when the voltage of the energy storage unit drops to a safe voltage threshold, thereby switching the load power supply to power the power supply module.

[0057] Specifically, during the discharge process, when the voltage drops to the set safe voltage threshold (such as 24V), the system will automatically switch to the load power supply mode to provide power through the load power supply terminal to ensure the stable operation of the energy storage system.

[0058] In some embodiments, an energy storage unit-side switch is connected between the power supply module and the energy storage unit, and a load power supply-side switch is connected between the power supply module and the load power supply. The energy storage unit includes a processor for controlling the closing of the energy storage unit-side switch and the opening of the load power supply-side switch in power consumption mode, thereby switching the energy storage unit to supply power to the power supply module.

[0059] Specifically, in the power consumption mode, while controlling the energy storage unit to only discharge and not charge, the energy storage unit supplies power to the power supply module to further consume the energy storage unit's power.

[0060] The energy storage unit-side switch and the load power supply-side switch can be relays or diode circuits, ensuring smooth switching between dual power supplies and preventing system instability caused by voltage fluctuations. Furthermore, to ensure voltage stability during switching, the system is designed with a voltage soft-start mechanism to reduce voltage surges during switching and guarantee the continuity and safety of the energy storage system.

[0061] The present embodiment will now be described and illustrated through preferred embodiments.

[0062] like Figure 2As shown, the energy storage system provided in this embodiment includes: an energy storage unit (capacitor), a converter, a memory, an elevator bus, a frequency converter, a processor, an interaction module, a power supply module, an elevator motor, a power management module (not shown in the figure), and a protection unit (not shown in the figure). In this embodiment, the energy storage system is applied to an elevator, that is, the load power supply is the elevator bus, which is located in the frequency converter. The DC-DC main circuit, i.e., the bidirectional conversion unit, is connected to the elevator bus in the frequency converter. The frequency converter is connected to the elevator motor. The frequency converter receives instructions from the processor and converts the DC power provided by the DC-DC main circuit into AC power with variable frequency and variable voltage to drive the elevator motor. The elevator motor controls the acceleration, constant speed, deceleration, and leveling of the elevator car according to the output signal of the frequency converter. When the elevator is in power-consuming mode, such as when it is fully loaded going upwards or unloaded going downwards, the elevator motor is in motor mode and can be powered by the energy storage unit or the mains power. The power from the energy storage unit and the mains power is transferred to the elevator through the frequency converter bus. The energy storage unit efficiently recovers electrical energy when the elevator operates in various power generation modes, such as braking, unloaded upward movement, and fully loaded downward movement. The elevator motor switches to generator mode, and the generated regenerative energy is fed back to the energy storage unit and the elevator bus via a frequency converter and converter, completing energy recovery. The DC-DC main circuit controls the charging and discharging switching between the energy storage unit and the elevator bus, enabling elevator power supply and energy recovery, reducing dependence on mains power and saving energy. The converter, located in the DC-DC main circuit, is connected to the energy storage unit, elevator bus, processor, and power supply module, and works in conjunction with the processor to achieve bidirectional power conversion, switching the charging and discharging states of the energy storage system and the elevator bus.

[0063] The power management module employs a high-precision voltage detection circuit to monitor the voltage of the energy storage unit in real time. The processor estimates the remaining power capacity based on the voltage and a preset discharge curve stored in the memory. The power management module is connected to the processor, and the memory stores multiple power levels. The processor adjusts the frequency and duty cycle of the PWM signal according to the estimated remaining power level to drive the converter and regulate the discharge power of the energy storage unit. This allows the voltage of the energy storage unit to gradually, efficiently, and safely decrease to the safe voltage threshold.

[0064] The power supply module is powered by the energy storage unit or the elevator bus, providing auxiliary power. This auxiliary power supply provides low voltage to the control chip, drive chip, sensors, communication module, and other components in the converter, thus improving conversion efficiency during energy conversion in the bidirectional conversion unit.

[0065] The interactive module can be installed in the elevator machine room, control cabinet, or other locations. When maintenance of the energy storage unit is required, relevant personnel can trigger the power consumption mode using physical or virtual touch-sensitive function buttons on the operating interface. In this mode, the processor controls the closing of the energy storage unit's side switch and the opening of the elevator bus side switch, switching the energy storage unit to supply power to the power supply module. The energy storage unit remains in a discharging state, without charging. During the discharge process, when the voltage drops to a set safe voltage threshold (e.g., 24V), the system automatically switches to the elevator bus power supply mode to ensure normal elevator operation.

[0066] The interactive module also includes a display interface that shows the status parameters of the energy storage unit (voltage, current, power, temperature, and cycle count). Voltage and residual current can be observed in real time to ensure the safety of maintenance operations.

[0067] The protection unit includes a pre-charge resistor, a fuse, and a circuit breaker, used to disconnect the bidirectional transfer unit from the energy storage unit and / or the elevator bus in the event of an abnormal current.

[0068] The aforementioned energy storage system provides safe discharge management and power consumption modes for the energy storage unit. The processor controls the converter with PWM signals of different duty cycles to adjust the discharge power of the energy storage unit. In the power consumption mode, the energy storage unit maintains a discharge state and performs discharge operations without charging, ensuring that the battery energy gradually, efficiently, and safely drops to the safe voltage threshold, which facilitates the removal, replacement, or recycling of the energy storage unit.

[0069] It should be understood that the specific embodiments described herein are merely illustrative of the application and not intended to limit it. All other embodiments derived by those skilled in the art based on the embodiments provided in this application without inventive effort are within the scope of protection of this application.

[0070] Obviously, the accompanying drawings are merely some examples or embodiments of this application. Those skilled in the art can apply this application to other similar situations based on these drawings without any creative effort. Furthermore, it is understood that although the work done in this development process may be complex and lengthy, for those skilled in the art, certain design, manufacturing, or production modifications made based on the technical content disclosed in this application are merely conventional technical means and should not be considered as insufficient disclosure of this application.

[0071] The term "embodiment" in this application refers to a specific feature, structure, or characteristic described in connection with an embodiment that may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily imply the same embodiment, nor does it imply that it is mutually exclusive with or alternative to other embodiments. It will be clearly or implicitly understood by those skilled in the art that the embodiments described in this application may be combined with other embodiments without conflict.

[0072] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of patent protection. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the appended claims.

Claims

1. An energy storage system, comprising: The power management module, and the energy storage unit and load power supply connected to the bidirectional conversion unit; characterized in that, The power management module is used to monitor the voltage of the energy storage unit; The bidirectional conversion unit is used to control the energy storage unit to remain in a discharging state in the power consumption mode until the voltage of the energy storage unit drops to a safe voltage threshold; wherein, The bidirectional conversion unit includes a memory, a processor, and a converter. The memory stores the safe voltage threshold. The processor is connected to the power management module, the memory, and the converter. The processor is used to receive the voltage of the energy storage unit in the power consumption mode and generate a PWM signal to drive the converter to adjust the voltage of the energy storage unit down to the safe voltage threshold.

2. The energy storage system according to claim 1, characterized in that, The memory also stores a preset discharge curve, and the processor is used to obtain the remaining power of the energy storage unit by using the voltage of the energy storage unit and the preset discharge curve.

3. The energy storage system according to claim 2, characterized in that, The memory also stores multiple power levels. When the remaining power is at different power levels, the processor generates different PWM signal duty cycles to drive the converter to adjust the discharge power of the energy storage unit.

4. The energy storage system according to claim 1, characterized in that, The energy storage system further includes: an interaction module connected to the processor, the interaction module including an operating interface; The user interface is equipped with function buttons for triggering the power consumption mode.

5. The energy storage system according to claim 4, characterized in that, The interactive module includes a display interface; The display interface is used to display the status parameters of the energy storage unit, including power, voltage and current.

6. The energy storage system according to claim 1, characterized in that, The bidirectional conversion unit further includes: a power supply module; The power supply module is powered by the energy storage unit or the load power supply and is used to provide power to the energy storage system.

7. The energy storage system according to claim 6, characterized in that, An energy storage unit-side switch is connected between the power supply module and the energy storage unit, and a load power supply-side switch is connected between the power supply module and the load power supply. The energy storage unit includes a processor, which controls the disconnection of the energy storage unit-side switch and the closing of the load power supply-side switch when the voltage of the energy storage unit drops to the safe voltage threshold, thereby switching the load power supply to power the power supply module.

8. The energy storage system according to claim 6, characterized in that, An energy storage unit-side switch is connected between the power supply module and the energy storage unit, and a load power supply-side switch is connected between the power supply module and the load power supply. The energy storage unit includes a processor, which is used to control the closing of the energy storage unit-side switch and the opening of the load power supply-side switch in power consumption mode, thereby switching the energy storage unit to supply power to the power supply module.

9. The energy storage system according to claim 1, characterized in that, The energy storage system also includes a protection unit; The protection unit includes a pre-charge resistor, a fuse, and a circuit breaker, used to disconnect the bidirectional conversion unit from the energy storage unit and / or the load power supply in the event of an abnormal current.

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