Power supply system suitable for rapid charging and discharging energy storage device

Abstract

The invention discloses a power supply system suitable for a rapid charging and discharging energy storage device. The system comprises a power supply unit, a direct current bus, an alternating current unit, a super capacitor device and a capacitor control unit, the output end of the alternating-current unit is connected with the direct-current bus through a cable, the input end of the alternating-current unit is connected with the capacitor management unit, and the direct-current bus is connected with the super-capacitor device. The AC unit adopts an AC / DC bidirectional converter and a DC / DC converter, the system can realize access of various AC and DC power supplies at the input end, such as a power grid, photovoltaic power generation and combination of the power grid and the photovoltaic power generation, green development of the super energy storage system is realized, and the intelligent electric energy monitoring device can monitor the power generation efficiency according to the power generation benefits in different seasons. A control strategy changing along with the system is formulated, and the benefits of energy conservation, efficiency improvement and carbon reduction are achieved.

Description

Technical Field

[0001] This invention relates to the field of energy storage technology, and more specifically to a power supply system suitable for fast charge and discharge energy storage devices. Background Technology

[0002] In the field of energy storage technology, supercapacitor energy storage systems can be used for grid power regulation and to provide grid power support. Supercapacitors store excess energy when load is low and feed it back to the grid during peak load periods to adjust power demand. They also provide rapid power buffering to address issues such as momentary power outages caused by system faults and sudden voltage spikes or dips, stabilizing and smoothing grid voltage fluctuations. Grids built around wind and solar power generation heavily rely on supercapacitors as a stabilizing system.

[0003] Compared to batteries, supercapacitors are mainly distinguished by their longer cycle life, wider operating temperature range, and maintenance-free operation. Their cycle life can reach 500,000 cycles, allowing for rapid deep charge-discharge cycles.

[0004] In the field of energy storage technology, there are various ways to charge supercapacitors, such as constant current charging, constant voltage charging, and pulse charging.

[0005] In photovoltaic power generation technology, DC power supply and distribution systems have advantages such as simple system structure and ease of control and scheduling. Summary of the Invention

[0006] The present invention proposes a power supply system suitable for fast charging and discharging energy storage devices, which can at least solve one of the technical problems in the background art.

[0007] To achieve the above objectives, the present invention adopts the following technical solution: A power supply system suitable for fast charge and discharge energy storage devices includes a power supply unit, a DC bus 102, an AC unit, a supercapacitor device, and a capacitor control unit; The power supply unit is connected to the AC unit. The output of the AC unit is connected to the DC bus via a cable. The input of the AC unit is connected to the capacitor management unit. The DC bus is connected to the supercapacitor device.

[0008] Furthermore, the AC unit of the present invention includes: a DC / DC converter and an AC / DC bidirectional converter connected in parallel.

[0009] Furthermore, the capacitor control unit of the present invention includes: The system comprises a supercapacitor management system, a capacitor cluster management unit, and a capacitor management unit. The supercapacitor management system is connected to the capacitor cluster management unit, which in turn is connected to multiple capacitor management units and AC units via data communication lines.

[0010] Furthermore, the supercapacitor device of the present invention includes: A pair of switches connected to the DC bus, one of which is connected to a current transformer at the other end, and the other switch is connected to a capacitor at the other end. The capacitor connected to the current transformer at the other end is connected to the negative terminal of the supercapacitor bank at the other end, and the capacitor connected to the switch at the other end is connected to the positive terminal of the supercapacitor bank at the other end. The supercapacitor bank consists of multiple supercapacitors and conductors connected in series.

[0011] Furthermore, the input terminals of all supercapacitors in this invention are connected to a DC bus, and the connected DC bus is selected by an electronic switch; the output of each supercapacitor is connected to a filter reactance, and the N groups of supercapacitors are identical, with the same output impedance parameters and the same power output capability.

[0012] As can be seen from the above technical solution, the photovoltaic DC direct charging power supply unit device of the present invention adopts an AC / DC bidirectional converter and a DC / DC converter, which can realize the access of multiple power sources, including the power grid, photovoltaic power generation, and the combination of power grid and photovoltaic power generation, at the input end, to achieve the green development of the super energy storage system. The intelligent power monitoring device can formulate control strategies that follow the changes in the system according to the power generation benefits in different seasons, so as to achieve the benefits of energy saving, efficiency improvement and carbon reduction. The fast charging and discharging energy storage device management system can realize the rapid response of the charging and discharging structure, ensure the balanced charging and discharging of parallel capacitors, monitor the voltage and temperature of each capacitor, ensure the stable operation of the power supply device, and provide stable and high-quality DC and AC power. The large rectification method adopted and the DC bus set can effectively reduce the amount of radial cable construction, simplify the original complex installation process, and speed up the construction and installation process. Attached Figure Description

[0013] Figure 1 This is a diagram of the management system architecture for the fast charge / discharge energy storage device of the present invention. Figure 2 This is a power supply topology diagram for the fast charge and discharge energy storage device according to the present invention.

[0014] In the diagram: 101, AC / DC bidirectional converter; 102, DC bus; 103, switch; 104, current transformer; 105, capacitor; 106, capacitor negative terminal; 107, capacitor positive terminal; 108, supercapacitor; 109, conductor; 110, supercapacitor bank casing; 111, DC / DC converter; 112, cable; 201, capacitor management unit; 202, capacitor cluster management unit; 203, supercapacitor management system; 204, data communication line; 301—AC power supply (transformer); 302—filter reactor; 303—photovoltaic power generation system; 304—photovoltaic energy monitoring device. Detailed Implementation

[0015] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are some embodiments of the present invention, but not all embodiments.

[0016] like Figure 1 As shown in this embodiment, a power supply system suitable for fast charge and discharge energy storage devices is provided. The system includes: a power supply unit, a DC bus 102, an AC unit, a supercapacitor device, and a capacitor control unit. The power supply unit is connected to the AC unit. The output of the AC unit is connected to the DC bus 102 via cable 112. The input of the AC unit is connected to the capacitor management unit 201. The DC bus 102 is connected to the supercapacitor device.

[0017] The DC bus terminal connection switch device can realize power draw from the DC bus terminal, and can realize multiple power supply methods such as DC power supply and AC power supply.

[0018] The power supply unit includes: a photovoltaic power generation unit and a photovoltaic energy monitoring device; The AC unit includes: a DC / DC converter 111 and an AC / DC bidirectional converter 101 connected in parallel; The transformer is an intelligent energy-saving transformer. The AC / DC bidirectional converter consists of an uncontrolled rectifier bridge and its compensation device, which can convert AC power from the grid into DC power or convert DC power from energy storage into AC power. The DC output terminal is a DC bus. The DC bus can also serve as the interface for a photovoltaic power generation system. When the photovoltaic system is connected to the DC / DC converter, the stable power supply voltage required by the photovoltaic system can be met. One DC bus is provided, and the voltage at both ends of the DC bus can be selected as 750V or 1500V. Energy monitoring devices are installed on both the converter output interface side and the photovoltaic system interface side to monitor the power flow direction in real time and solve the interface problem of selecting the power direction of the DC bus.

[0019] The capacitor control unit includes: a supercapacitor management system 203, a capacitor cluster management unit 202, and a capacitor management unit 201. The supercapacitor management system 203 is connected to the capacitor cluster management unit 202, and the capacitor cluster management unit 202 is connected to multiple capacitor management units 201 and AC units via a data communication line 204.

[0020] The supercapacitor device includes: a pair of switches 103 connected to a DC bus 102, wherein one switch 103 is connected to a current transformer 104 at one end, the other switch is connected to a capacitor 105, the other end of the current transformer 104 is connected to the capacitor 105, the other end of the capacitor connected to the current transformer 104 is connected to the negative terminal 106 of the supercapacitor bank, and the other end of the capacitor connected to the switch is connected to the positive terminal 107 of the supercapacitor bank.

[0021] The supercapacitor group 110 includes multiple supercapacitors 108 connected in series and conductors 109.

[0022] The supercapacitor device contains N (N=5) groups of supercapacitors, all of which have their input terminals connected to a DC bus. The connected DC bus can be selected via an electronic switch. Each supercapacitor's output is connected to a filter reactor. The N groups of supercapacitors are identical, with the same output impedance parameters and power output capabilities. The device features AC / DC bidirectional converter, and the output is connected to the AC output bus.

[0023] This solution also provides a power supply structure suitable for fast charge and discharge energy storage devices; like Figure 2 As shown, the power supply structure of the fast charge and discharge energy storage device includes five supercapacitors 110 operating in parallel, connected to a current transformer 104 via cable 112, and connected to the DC bus 102 via cable 112 and switch 103. The DC / DC converter 111 and the AC / DC bidirectional converter 101 are respectively connected to the DC bus 102 via cable 112. Energy exchange between DC power and AC power can be realized through the DC / DC converter 111 and the AC / DC bidirectional converter 101.

[0024] Figure 1 The supercapacitor management system 203 employs a three-tier network architecture. Each supercapacitor enclosure is managed by a supercapacitor cluster management unit 202, which is responsible for functions such as individual supercapacitor voltage and temperature acquisition, and equalization. The supercapacitor cluster management unit 202 communicates via a bus, while individual supercapacitor information is transmitted upwards by the capacitor management unit 201.

[0025] Each supercapacitor cluster is equipped with one supercapacitor cluster management unit 202, which collects the total voltage and current of the supercapacitor cluster, controls the circuit breaker of the supercapacitor group, and communicates data with the upstream. The supercapacitor management system 203 connects to the inverter via a communication cable.

[0026] The main functions of the supercapacitor storage management unit 202 are: Real-time monitoring of the voltage and temperature of individual supercapacitors; 16 temperatures are configured for 32 cells. It supports a 16+16 acquisition mode (supports connecting only 1 cell), with each module of 16 supercapacitors corresponding to one terminal, featuring a fully modular design; the module has dry contact output, enabling on-site alarm or remote control; the module has passive balancing, improving the consistency of the supercapacitor group and effectively extending the supercapacitor's lifespan. Key specifications of the supercapacitor bank management unit 202: Module power supply voltage: DC24V±20%; Maximum power supply: <2W; Number of supercapacitor monitoring sections: 32; Voltage detection range: 0~5V; Voltage detection accuracy: ±0.2%; Number of temperature sensors: 16; Temperature detection range: -40~125℃; Temperature detection accuracy: ±1℃; Overcapacity balancing method: passive balancing; Capacitor balancing current: 50mA; Data communication interface: CAN; Input insulation resistance: ≥10MΩ, 2500VDC; The supercapacitor group control unit collects the voltage and current data of the entire supercapacitor group in real time, has the function of controlling the DC circuit on and off, and has the function of real-time detection of the status of on-site alarm equipment and uploading the data to the energy storage system management unit.

[0027] (1) Main functions of the control module for the energy storage supercapacitor bank; (2) Online automatic detection of voltage, current and ambient temperature of the entire supercapacitor bank; (3) Real-time alarm function to realize over-limit alarm for the entire group of voltage and current; (4) On-site alarm and switch quantity detection function, which can realize remote computer alarm and display alarm content.

[0028] In summary, the AC / DC bidirectional converter and DC / DC converter used in this invention can connect to multiple AC and DC power sources at the input end: the power grid, photovoltaic power generation, and a combination of power grid and photovoltaic power generation, realizing the green development of the super energy storage system. The intelligent power monitoring device can formulate control strategies that follow system changes based on the power generation benefits in different seasons, achieving energy saving, efficiency improvement, and carbon reduction benefits. The fast charge and discharge energy storage device management system can realize rapid response of the charging and discharging structure, ensure balanced charging and discharging of parallel capacitors, monitor the voltage and temperature of each capacitor, ensure stable operation of the power supply device, and provide stable and high-quality DC and AC power. The large rectification method and the setting of DC bus can effectively reduce the amount of radial cable construction, simplify the original complex installation process, and accelerate the construction and installation process.

[0029] Under the basic supercapacitor management system, rapid charging and discharging of DC and AC energy can be achieved, enriching the power supply forms of energy storage systems, simplifying the energy storage structure of photovoltaic systems, and improving the utilization rate of power capacity within the system.

[0030] Leveraging the rapid charging and discharging capabilities of supercapacitors, a composite power input terminal is established, connecting a DC bus to a DC / DC converter, an AC / DC bidirectional converter, and a photovoltaic power generation system. This enables simultaneous AC and DC power supply or a combination of multiple functions. It expands the possibilities for green energy access methods and energy storage structures, promoting the development of green energy. Intelligent current monitoring devices and energy storage management systems can determine the optimal power system access and operation mode.

[0031] Employing a supercapacitor management system, the system monitors capacitor cell voltage, current, temperature, and equalization to control simultaneous charging and discharging of the capacitor bank, ensuring stable operation of the energy storage device. During stable operation, the system effectively utilizes the designed capacity of the units, improving power utilization, system economy, and reliability. Multiple AC and DC power interface modes provide diverse operating options, enabling varied operational modes and offering multiple backup plans to ensure stable system operation in case of system failures. For instantaneous power outages and voltage spikes caused by system failures, the fast-charging and discharging energy storage device provides rapid response, offering fast, high-power buffering to stabilize and smooth grid voltage fluctuations, thus ensuring the stable operation of the grid built upon wind and solar power generation.

[0032] This invention represents the advanced nature of fast-charging and discharging energy storage devices and has significant economic and social benefits.

[0033] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0034] The various embodiments in this specification are described in a related manner. Similar or identical parts between embodiments can be referred to mutually. Each embodiment focuses on describing the differences from other embodiments. In particular, the system embodiments are basically similar to the method embodiments, so the description is relatively simple; relevant parts can be referred to the descriptions of the method embodiments.

[0035] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A power supply system suitable for fast-charging and discharging energy storage devices, characterized in that, include: Power supply unit, DC bus 102, AC unit, supercapacitor device, capacitor control unit; The power supply unit is connected to the AC unit. The output end of the AC unit is connected to the DC bus (102) via cable (112). The input end of the AC unit is connected to the capacitor management unit (201). The DC bus (102) is connected to the supercapacitor device.

2. The power supply system for a fast-charging and discharging energy storage device according to claim 1, characterized in that, The AC unit includes: a DC / DC converter (111) connected in parallel and an AC / DC bidirectional converter (101).

3. The power supply system for a fast-charging and discharging energy storage device according to claim 1, characterized in that, The capacitor control unit includes: The system includes a supercapacitor management system (203), a capacitor cluster management unit (202), and a capacitor management unit (201). The supercapacitor management system (203) is connected to the capacitor cluster management unit (202), and the capacitor cluster management unit (202) is connected to multiple capacitor management units (201) and AC units via a data communication line (204).

4. The power supply system for a fast-charging and discharging energy storage device according to claim 3, characterized in that, The supercapacitor device includes: A pair of switches (103) are connected to the DC bus (102). One switch (103) is connected to a current transformer (104) at one end, and the other switch is connected to a capacitor (105). The other end of the current transformer (104) is connected to the capacitor (105). The other end of the capacitor connected to the current transformer (104) is connected to the negative terminal (106) of the supercapacitor bank. The other end of the capacitor connected to the switch is connected to the positive terminal (107) of the supercapacitor bank. The supercapacitor group (110) includes multiple supercapacitors (108) connected in series and conductors (109).

5. The power supply system for a fast-charging and discharging energy storage device according to claim 4, characterized in that, The input terminals of all supercapacitors are connected to a DC bus, and the connected DC bus is selected by an electronic switch; the output of each supercapacitor is connected to a filter reactance, and the N groups of supercapacitors are identical, with the same output impedance parameters and the same power output capability.

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