Distributed source network load storage micro-grid system

Abstract

The invention discloses a distributed source network load storage micro-grid system, which comprises an intelligent micro-grid, a plurality of distributed intelligent charging control terminals and a scheduling control system, the distributed intelligent charging control terminal comprises a central controller, a wireless communication module, a controllable inverter, a controllable rectifier, a direct current charging load, a distributed photovoltaic power supply and a low-temperature superconducting film capacitor energy storage system. Wherein the low-temperature superconducting thin film capacitor energy storage system comprises a plurality of energy storage modules arranged in an underground low-temperature closed metal cabin, and each energy storage module is formed by connecting a plurality of low-temperature superconducting thin film capacitors in parallel; wherein a refrigeration system of the metal cabin adopts a semiconductor refrigeration technology, and a temperature and humidity monitor and a thin-film capacitor voltage monitoring system are arranged in the metal cabin; electric energy generated by the distributed photovoltaic power supply in real time is stored in the low-temperature superconducting thin film capacitor energy storage system and is used by the distributed intelligent charging control terminal.

Description

Technical Field

[0001] The present invention belongs to the technical field of power grids, and more specifically, relates to a distributed source-grid-load-storage microgrid system. Background Art

[0002] With the widespread access to smart charging piles, charging of new energy vehicles is becoming increasingly convenient. However, due to the large load fluctuation and high uncertainty, the smart charging system is not integrated into the large power grid, and its DC energy is taken from the rectified AC power.

[0003] In the related technology, a microgrid model suitable for distributed photovoltaic power supply and intelligent charging pile load access is proposed. However, the power transmission capacity of the existing microgrid model is affected by the volatility of distributed power supply and load, the line voltage volatility is large, the stability is low, and for the low-voltage power grid structure, the transmission distance is short. By adding distributed energy storage equipment to the microgrid structure, the stability of DC power transmission can be greatly improved, and the transmission distance can be increased at the same time. However, the energy storage equipment currently used in the power grid architecture is mainly electrochemical energy storage, which has poor safety, short service life, and high damage rate, and is not suitable for microgrid systems. Compared with traditional electrochemical energy storage equipment, film capacitors have the advantages of high safety factor, long service life, not easy to damage, and good corrosion resistance, but their energy storage density is low. The capacity stored in film capacitors under the same volume cannot meet the needs of high-power power transmission of the power grid, and large-capacity film capacitors need to occupy a large space, which is difficult to meet the requirements of the intensive intelligent charging piles.

[0004] Therefore, how to improve the effect of electric energy storage in distributed source-grid-load storage and avoid operating problems caused by the shortcomings of electrochemical energy storage devices is a key issue that technicians in this field are concerned about. Summary of the invention

[0005] The purpose of this application is to provide a distributed source-grid-load-storage microgrid system to improve the effect of electric energy storage in the distributed source-grid-load-storage microgrid system and avoid the problems of insufficient energy storage and large space occupied by energy storage components.

[0006] In view of the above defects or improvement needs of the prior art, the present invention provides a distributed source-grid-load-storage microgrid system, including: an intelligent microgrid, a plurality of distributed intelligent charging control terminals, and a dispatching control system;

[0007] The smart microgrid is used to adjust the photovoltaic power system and the AC mains system, and the smart microgrid includes: an electric energy monitoring and control system, and a smart microgrid AC cable;

[0008] The distributed intelligent charging control terminal includes: a central controller, a wireless communication module, a controllable inverter, a controllable rectifier, a DC charging load, a distributed photovoltaic power source, and a low-temperature superconducting film capacitor energy storage system;

[0009] The low-temperature superconducting film capacitor energy storage system includes a plurality of energy storage modules arranged in an underground low-temperature sealed metal cabin, and the energy storage module is composed of a plurality of low-temperature superconducting film capacitors connected in parallel; the refrigeration system of the metal cabin adopts semiconductor refrigeration technology, and a temperature and humidity monitor and a film capacitor voltage monitoring system are arranged in the metal cabin; the electric energy generated in real time by the distributed photovoltaic power source is stored in the low-temperature superconducting film capacitor energy storage system for use by the distributed intelligent charging control terminal;

[0010] Wherein, the dispatching control system includes: a dispatching pan-tilt station and a communication control main station.

[0011] Optionally, the distributed intelligent charging control terminal also includes: an intelligent charging pile; the distributed intelligent charging control terminal is used to output a driving signal to control the DC power generated by the distributed photovoltaic power source to output a voltage-stable industrial frequency AC power after passing through the controllable inverter, and incorporate it into the smart microgrid; the charging load of the smart charging pile is taken from the voltage and current controllable DC power obtained after the AC power of the smart microgrid is processed by the controllable rectifier.

[0012] Optionally, the distributed photovoltaic power source is used to generate direct current power through photovoltaic modules.

[0013] Optionally, the low-temperature superconducting film capacitor energy storage system is used to store the electric energy generated by the distributed photovoltaic power source through low-temperature superconducting film capacitors.

[0014] Optionally, the first power supply of the smart microgrid is the surplus electric energy of the distributed photovoltaic power supply, and the second power supply is the AC mains with the same frequency and voltage; the first power supply and the second power supply serve as backup for each other, and the first power supply is used as the main power supply; when the power generation of the distributed photovoltaic power supply is lower than the preset power generation value or the DC charging load is higher than the preset load value, the backup power supply is enabled; when the backup power supply fails or the line is shut down for maintenance, the smart microgrid is powered by the distributed photovoltaic power supply.

[0015] Optionally, the electric energy monitoring and control system is used to monitor the electric energy of the first power supply and the second power supply of the smart microgrid respectively, obtain monitoring results, and perform grid connection control based on the monitoring results.

[0016] Optionally, the smart microgrid AC cable is used to connect to an AC mains grid.

[0017] Optionally, the dispatching and control system is used to obtain real-time data of the multiple distributed intelligent charging control terminals and the smart microgrid, analyze and process the real-time data, determine the real-time power dispatching strategy based on the analysis results, and send control signals to the distributed intelligent charging control terminals and the electric energy monitoring and control system based on the real-time power dispatching strategy, so as to drive the corresponding controllable inverter to output the DC power stored in the low-temperature superconducting thin film capacitor energy storage system to the smart microgrid; the controllable rectifier inputs the AC power of the smart microgrid into the smart charging pile with a charging load, so as to realize flexible dispatching of the DC power output by the distributed photovoltaic power source and convert it into the power of the DC charging load.

[0018] Optionally, the communication control master station is used to communicate in real time with the distributed intelligent charging control terminal and the electric energy monitoring and control system of the intelligent microgrid through a wireless communication module.

[0019] Optionally, the dispatching cloud platform is used to receive in real time the charging load data collected by the distributed intelligent charging control terminal, the DC voltage data of the energy storage system, and the microgrid power quality data collected by the electric energy monitoring and control system.

[0020] A distributed source-grid-load-storage microgrid system provided in the present application includes: an intelligent microgrid, multiple distributed intelligent charging control terminals, and a dispatching control system; wherein the intelligent microgrid is used to regulate a photovoltaic power system and an AC mains system, and the intelligent microgrid includes: an electric energy monitoring and control system, and an intelligent microgrid AC cable; wherein the distributed intelligent charging control terminal includes: a central controller, a wireless communication module, a controllable inverter, a controllable rectifier, a DC charging load, a distributed photovoltaic power source, and a low-temperature superconducting film capacitor energy storage system; wherein the low-temperature superconducting film capacitor energy storage system includes a plurality of energy storage modules arranged in an underground low-temperature sealed metal cabin, and the energy storage module is composed of a plurality of low-temperature superconducting film capacitors connected in parallel; wherein the refrigeration system of the metal cabin adopts semiconductor refrigeration technology, and a temperature and humidity monitor and a film capacitor voltage monitoring system are arranged in the metal cabin; the electric energy generated in real time by the distributed photovoltaic power source is stored in the low-temperature superconducting film capacitor energy storage system for use by the distributed intelligent charging control terminal; wherein the dispatching control system includes: a dispatching pan / tilt and a communication control master station.

[0021] It has the following beneficial effects:

[0022] Through the underground low-temperature superconducting film capacitor energy storage system, distributed photovoltaic, thin film energy storage, and smart charging piles are integrated, and the smart charging piles are reliably connected to the microgrid system. This improves the energy storage performance of the microgrid, improves the effect of the microgrid after grid connection, and improves the stability and security of the power grid. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying any creative work.

[0024] Figure 1 A schematic structural diagram of a distributed source-grid-load-storage microgrid system provided in an embodiment of the present application. DETAILED DESCRIPTION

[0025] The core of this application is to provide a distributed source-grid-load-storage microgrid system to improve the effect of electric energy storage in the distributed source-grid-load-storage microgrid system and avoid the problems of insufficient energy storage and large space occupied by energy storage components.

[0026] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0027] The following is an explanation of a distributed source-grid-load-storage microgrid system provided by the present application through an embodiment.

[0028] Please refer to Figure 1 , Figure 1 A schematic structural diagram of a distributed source-grid-load-storage microgrid system provided in an embodiment of the present application.

[0029] In this embodiment, the system may include:

[0030] Smart microgrid 1, multiple distributed smart charging control terminals 2, dispatching control system 3;

[0031] Among them, the smart microgrid 1 is used to adjust the photovoltaic power system and the AC mains system, and the smart microgrid 1 includes: an electric energy monitoring and control system, and a smart microgrid 1 AC cable;

[0032] Among them, the distributed intelligent charging control terminal 2 includes: a central controller, a wireless communication module, a controllable inverter, a controllable rectifier, a DC charging load, a distributed photovoltaic power source, and a low-temperature superconducting film capacitor energy storage system;

[0033] Among them, the low-temperature superconducting film capacitor energy storage system includes multiple energy storage modules arranged in an underground low-temperature sealed metal cabin, and the energy storage module is composed of multiple low-temperature superconducting film capacitors connected in parallel; wherein, the refrigeration system of the metal cabin adopts semiconductor refrigeration technology, and a temperature and humidity monitor and a film capacitor voltage monitoring system are arranged in the metal cabin; the electric energy generated in real time by the distributed photovoltaic power source is stored in the low-temperature superconducting film capacitor energy storage system for use by the distributed intelligent charging control terminal 2;

[0034] Among them, the dispatching control system 3 includes: a dispatching pan-tilt station and a communication control main station.

[0035] The energy storage system uses cable reels made of film capacitors as energy storage modules, and can use a multi-layer parallel structure to increase its capacitance value. It is space-intensive, environmentally friendly, safe and stable, and the internal insulation medium of the film capacitor uses high-temperature and corrosion-resistant materials, which has a long service life. In order to reduce resistance loss, it can be laid in an underground capacitor warehouse and cooled.

[0036] The width of the metal foil of the thin film capacitor cable is the length of the cable, and the length is positively correlated with the number of turns of the cable layer. The metal foil has a large area and a large conductive cross-sectional area, so it has the advantages of both large capacitance and low resistance. At the same time, the cable disc structure can save vertical distribution space. The use of a layered parallel structure in the vertical direction can further increase the total capacitance value, thereby achieving the effect of increasing the energy storage capacity.

[0037] At the same time, in order to improve the stability of the capacitor, the cable uses mica paper crimped with a hard flame-retardant insulating shell to reliably fix the shape of the cable reel. The parallel structure between multiple layers can be detached and connected to the voltage monitoring system respectively to monitor voltage fluctuations in real time. If one of the sections has a local breakdown and the capacitance value is reduced, it can continue to operate without affecting the overall performance of the capacitor group, but it can be replaced by a power outage when necessary.

[0038] In order to reduce the heat loss caused by the resistance of the film capacitor, the metal cabin of the film capacitor is treated with low temperature to reach the critical temperature of film superconductivity, so the film capacitor has low-temperature superconductivity. The refrigeration system in the metal cabin is based on semiconductor refrigeration technology, which has the advantages of cleanliness, pollution-free, emission reduction and consumption reduction.

[0039] In summary, this embodiment realizes the integrated layout of distributed photovoltaic, thin film energy storage, and smart charging piles through the underground low-temperature superconducting thin film capacitor energy storage system, and reliably connects the smart charging piles to the microgrid system. As the energy storage performance of the microgrid is improved, the effect of the microgrid after grid connection is improved, and the stability and safety of the power grid are improved.

[0040] Optionally, the distributed intelligent charging control terminal 2 also includes: an intelligent charging pile; the distributed intelligent charging control terminal 2 is used to output a driving signal to control the DC power generated by the distributed photovoltaic power source to output a stable-voltage industrial frequency AC power after passing through a controllable inverter and be incorporated into the smart microgrid 1; the charging load of the smart charging pile is obtained from the voltage and current controllable DC power obtained after the AC power of the smart microgrid 1 is processed by a controllable rectifier.

[0041] Optionally, a distributed photovoltaic power source is used to generate DC power through photovoltaic modules.

[0042] Optionally, a low-temperature superconducting film capacitor energy storage system is used to store the electrical energy generated by distributed photovoltaic power sources through low-temperature superconducting film capacitors.

[0043] Optionally, the first power supply of the smart microgrid 1 is the surplus electric energy of the distributed photovoltaic power supply, and the second power supply is the AC mains with the same frequency and voltage; the first power supply and the second power supply serve as backup for each other, and the first power supply is used as the main power supply; when the power generation of the distributed photovoltaic power supply is lower than the preset power generation value or the DC charging load is higher than the preset load value, the backup power supply is enabled; when the backup power supply fails or the line is shut down for maintenance, the smart microgrid 1 is powered by the distributed photovoltaic power supply.

[0044] Optionally, an electric energy monitoring and control system is used to monitor the electric energy of the first power supply and the second power supply of the smart microgrid 1 respectively, obtain monitoring results, and perform grid connection control based on the monitoring results.

[0045] Optionally, the smart microgrid 1 AC cable is used to connect to the AC mains grid.

[0046] Optionally, the dispatching and control system 3 is used to obtain real-time data of multiple distributed intelligent charging control terminals 2 and intelligent microgrids 1, analyze and process the real-time data, determine the real-time power dispatching strategy based on the analysis results, and send control signals to the distributed intelligent charging control terminals 2 and the electric energy monitoring and control system based on the real-time power dispatching strategy, so as to drive the corresponding controllable inverter to output the DC power stored in the low-temperature superconducting film capacitor energy storage system to the intelligent microgrid 1; the controllable rectifier inputs the AC power of the intelligent microgrid 1 to the intelligent charging pile with charging load, so as to realize the flexible dispatching of the DC power output by the distributed photovoltaic power source and convert it into the power of the DC charging load.

[0047] Optionally, the communication control master station is used to communicate in real time with the distributed intelligent charging control terminal 2 and the electric energy monitoring and control system of the intelligent microgrid 1 through a wireless communication module.

[0048] Optionally, a dispatching PTZ is used to receive in real time the charging load data collected by the distributed intelligent charging control terminal 2, the DC voltage data of the energy storage system, and the microgrid power quality data collected by the electric energy monitoring and control system.

[0049] The various embodiments in the specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part description.

[0050] Professionals may further appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of the two. In order to clearly illustrate the interchangeability of hardware and software, the composition and steps of each example have been generally described in the above description according to function. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professionals and technicians may use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0051] The steps of the method or algorithm described in conjunction with the embodiments disclosed herein may be implemented directly using hardware, a software module executed by a processor, or a combination of the two. The software module may be placed in a random access memory (RAM), a memory, a read-only memory (ROM), an electrically programmable ROM, an electrically erasable programmable ROM, a register, a hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art.

[0052] The above is a detailed introduction to a distributed source-grid-load-storage microgrid system provided by the present application. This article uses specific examples to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method of the present application and its core idea. It should be pointed out that for ordinary technicians in this technical field, without departing from the principles of the present application, several improvements and modifications can be made to the present application, and these improvements and modifications also fall within the scope of protection of the claims of the present application.

Claims

1. A distributed source-grid-load-storage microgrid system, characterized in that: include: Smart microgrid, multiple distributed smart charging control terminals, and dispatching control systems; The smart microgrid is used to adjust the photovoltaic power system and the AC mains system, and the smart microgrid includes: an electric energy monitoring and control system, and a smart microgrid AC cable; The distributed intelligent charging control terminal includes: a central controller, a wireless communication module, a controllable inverter, a controllable rectifier, a DC charging load, a distributed photovoltaic power source, and a low-temperature superconducting film capacitor energy storage system; The low-temperature superconducting film capacitor energy storage system includes a plurality of energy storage modules arranged in an underground low-temperature sealed metal cabin, and the energy storage module is composed of a plurality of low-temperature superconducting film capacitors connected in parallel; the refrigeration system of the metal cabin adopts semiconductor refrigeration technology, and a temperature and humidity monitor and a film capacitor voltage monitoring system are arranged in the metal cabin; the electric energy generated in real time by the distributed photovoltaic power source is stored in the low-temperature superconducting film capacitor energy storage system for use by the distributed intelligent charging control terminal; Wherein, the dispatching control system includes: a dispatching pan-tilt station and a communication control main station.

2. The microgrid system according to claim 1, characterized in that: The distributed intelligent charging control terminal also includes: an intelligent charging pile; the distributed intelligent charging control terminal is used to output a driving signal to control the DC power generated by the distributed photovoltaic power source to output a stable voltage industrial frequency AC power after passing through the controllable inverter and be incorporated into the intelligent microgrid; the charging load of the intelligent charging pile is obtained from the voltage and current controllable DC power obtained after the AC power of the intelligent microgrid is processed by the controllable rectifier.

3. The microgrid system according to claim 2, characterized in that: The distributed photovoltaic power source is used to generate direct current electric energy through photovoltaic modules.

4. The microgrid system according to claim 3, characterized in that: The low-temperature superconducting film capacitor energy storage system is used to store the electric energy generated by the distributed photovoltaic power source through low-temperature superconducting film capacitors.

5. The microgrid system according to claim 4, characterized in that: The first power supply of the smart microgrid is the surplus electric energy of the distributed photovoltaic power supply, and the second power supply is the AC mains with the same frequency and voltage; the first power supply and the second power supply are backup for each other, and the first power supply is used as the main power supply; when the power generation of the distributed photovoltaic power supply is lower than the preset power generation value or the DC charging load is higher than the preset load value, the backup power supply is enabled; when the backup power supply fails or the line is shut down for maintenance, the smart microgrid is powered by the distributed photovoltaic power supply.

6. The microgrid system according to claim 5, characterized in that: The electric energy monitoring and control system is used to monitor the electric energy of the first power supply and the second power supply of the smart microgrid respectively, obtain monitoring results, and perform grid connection control based on the monitoring results.

7. The microgrid system according to claim 6, characterized in that: The smart microgrid AC cable is used to connect to an AC mains grid.

8. The microgrid system according to claim 7, characterized in that: The dispatching and control system is used to obtain real-time data of the multiple distributed intelligent charging control terminals and the intelligent microgrid, analyze and process the real-time data, determine the real-time power dispatching strategy based on the analysis results, and send control signals to the distributed intelligent charging control terminals and the electric energy monitoring and control system based on the real-time power dispatching strategy, so as to drive the corresponding controllable inverter to output the DC power stored in the low-temperature superconducting film capacitor energy storage system to the intelligent microgrid; the controllable rectifier inputs the AC power of the intelligent microgrid to the intelligent charging pile with charging load, so as to realize the flexible dispatching of the DC power output by the distributed photovoltaic power source and convert it into the power of the DC charging load.

9. The microgrid system according to claim 8, characterized in that: The communication control master station is used to communicate in real time with the distributed intelligent charging control terminal and the electric energy monitoring and control system of the intelligent microgrid through a wireless communication module.

10. The microgrid system according to claim 9, characterized in that: The dispatching cloud platform is used to receive in real time the charging load data collected by the distributed intelligent charging control terminal, the DC voltage data of the energy storage system, and the microgrid power quality data collected by the electric energy monitoring and control system.

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