Electric energy router-based micro-grid system for transformer substation

Abstract

The invention relates to the technical field of substation power supply system design, and discloses a substation micro-grid system based on an electric energy router, which comprises a traditional substation power utilization system, the electric energy router, a wind power generation and photovoltaic power generation system and an energy storage system, a traditional substation power utilization system comprises an out-of-station power supply, an in-station low-voltage bus, a station transformer, an ATS switching device and a 380V bus, and an electric energy router is connected with each section of the 380V bus and is provided with an AC-DC module and a flexible interconnection function; new energy power generation, energy storage charging and discharging and station load power utilization coordinated operation are controlled through the electric energy router, green energy is used for supplying power to a substation station power utilization load, power transmission and transformation investment and operation cost are saved, line loss of concentrated power transmission is reduced, power supply with a large power grid is complementary, power grid capacity is reduced, and power grid peak and valley performance is improved. And meanwhile, pollution to the environment can be reduced, and remarkable economic and social benefits are achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of the design of substation station power supply systems, and particularly relates to a substation station microgrid system based on an energy router. Background Art

[0002] The substation station power supply system is an important link to ensure the safe and reliable operation of the substation. Once a fault occurs in the station power supply system, it will directly or indirectly affect the safe and reliable operation of the substation. In severe cases, it will expand the scope of the accident and lead to serious accidents such as power grid disconnection.

[0003] The traditional substation station power supply comes from the power grid system, consuming a large amount of power grid electric energy. Although the related equipment and technologies of new energy and renewable energy have been continuously developed, the traditional substation station power supply system cannot achieve efficient utilization of green electricity. Summary of the Invention

[0004] The purpose of the present invention is to solve the above problems by designing a substation station microgrid system based on an energy router, which combines the traditional power grid, new energy power generation and energy storage technologies, and at the same time adopts automatic control to realize the coordinated operation of power generation, energy storage charging and discharging, and the power consumption end, further constructing an intelligent and green power grid.

[0005] The present invention provides a substation station microgrid system based on an energy router. The substation station microgrid system based on an energy router includes a traditional substation station power supply system, an energy router, a wind power generation and photovoltaic power generation system, and an energy storage system. Among them,

[0006] The traditional substation station power supply system includes an off-site power supply, an in-station low-voltage bus, a station transformer, an ATS switching device, and a 380V bus. The off-site power supply cooperates with the in-station low-voltage bus through the station transformer. The ATS switching device ensures the continuity of power supply, and the 380V bus supplies power to the station loads.

[0007] The energy router is connected to each section of the 380V bus and has an AC-DC module and a flexible interconnection function.

[0008] The wind power generation and photovoltaic power generation system converts the generated alternating current into direct current through the AC-DC module of the energy router and then accesses the 380V bus. When the power generation is excessive, the excess electric energy is stored in the energy storage system; when the power generation is insufficient, the energy storage system releases electric energy to meet the demand of the station loads.

[0009] The energy storage system is connected to the energy router, stores electric energy when the new energy power generation is excessive, and releases electric energy when the power generation is insufficient or during the peak period of the station loads, smoothing the fluctuations of the new energy power generation and stabilizing the power supply.

[0010] Optionally, in the first implementation mode of the present invention, the traditional substation station power supply system is powered by the 1# station transformer, 2# station transformer, and 0# station transformer. The off-site power supply is connected to the 0# station transformer through the 3DL switch, the in-station low-voltage section I bus is connected to the 1# station transformer through the 1DL switch, and the in-station low-voltage section II bus is connected to the 2# station transformer through the 2DL switch.

[0011] Optionally, in the second implementation mode of the present invention, the traditional substation station power supply system includes 3 incoming switch cabinets for the station power supply system and 8 feeder switch cabinets for the station power supply system. The incoming switch cabinet 1 for the station power supply system contains the 11QF incoming switch and the ATS switching device 1. The incoming switch cabinet 2 for the station power supply system contains the 12QF incoming switch and the 22QF incoming switch. The incoming switch cabinet 3 for the station power supply system contains the 21QF incoming switch and the ATS switching device 2.

[0012] Optionally, in the third implementation mode of the present invention, the 1# station transformer is connected to one end of the ATS switching device 1 through the 11QF switch, and the 2# station transformer is connected to one end of the ATS switching device 2 through the 21QF switch. The 0# station transformer is connected to the other end of the ATS switching device 1 and the ATS switching device 2 through the 12QF switch and the 22QF switch respectively.

[0013] Optionally, in the fourth implementation mode of the present invention, the output end of the ATS switching device 1 is connected to the 380V section I bus, and the output end of the ATS switching device 2 is connected to the 380V section II bus.

[0014] Optionally, in the fifth implementation mode of the present invention, the 380V section I bus and the 380V section II bus are connected through the flexible interconnection module of the power router. The AC-DC module of the power router is respectively connected to the 380V section I bus and the 380V section II bus.

[0015] Optionally, in the sixth implementation mode of the present invention, the 380V section I bus and the 380V section II bus are also respectively connected to multiple station loads. At the same time, photovoltaic, wind power, and energy storage devices are connected to the 380V bus through the power router.

[0016] Optionally, in the seventh implementation mode of the present invention, the 8 feeder switch cabinets for the station power supply system are divided into 4 feeder switch cabinets for the section I bus and 4 feeder switch cabinets for the section II bus according to the bus. The feeder switch cabinet for the section I bus contains the power supply branch air switches for the 11CK, 12CK, and 13CK station loads under the 380V section I bus and the 1JK air switch for accessing the power router. The feeder switch cabinet for the section II bus contains the power supply branch air switches for the 21CK, 22CK, and 23CK station loads under the 380V section II bus and the 2JK air switch for accessing the power router.

[0017] In the technical solution provided by the present invention, a distributed power source is set up in a substation, including new energy power generation such as wind power generation and photovoltaic power generation, energy storage, etc. It is connected to the existing substation station service power system, and the new energy power generation, energy storage charging and discharging, and the coordination operation of the station service load power consumption are controlled through an electric energy router. The green energy is used to supply power to the substation station service load, saving the investment and operation costs of power transmission and transformation, reducing the line loss of centralized power transmission; being complementary to the power supply of the large power grid, reducing the power grid capacity, improving the peak-valley performance of the power grid, improving the power supply reliability, and at the same time reducing environmental pollution, with significant economic and social benefits; improving the power supply reliability: through multi-power source access, ATS switching device, and the flexible interconnection function of the electric energy router, when an external power supply failure or an in-station equipment failure occurs, the power source can be quickly switched to ensure the continuous power supply of the station service load; the electric energy router can flexibly convert and distribute the electric energy of different types of power sources (such as photovoltaic and wind power) to adapt to different operating conditions and load requirements; it can effectively connect distributed energy sources such as photovoltaic and wind power, realize the local consumption of new energy, reduce the dependence on the traditional power grid, and improve the energy utilization efficiency. Description of the Drawings

[0018] By reading the detailed description of the preferred embodiments below, various other advantages and benefits will become clear to those of ordinary skill in the art. The drawings are only for the purpose of showing the preferred embodiments and are not considered to be a limitation of the present invention.

[0019] Figure 1 It is a schematic diagram of a substation station service microgrid system based on an electric energy router provided by an embodiment of the present invention. Detailed Embodiments

[0020] The terms "first", "second", "third", "fourth", etc. (if any) in the specification, claims and above drawings of the present invention are used to distinguish similar objects and do not have to be used to describe a specific order or sequence. It should be understood that such data can be interchanged under appropriate circumstances so that the embodiments described herein can be implemented in an order different from that shown or described herein. In addition, the terms "comprising" or "having" and any variation thereof are intended to cover non-exclusive inclusion. For example, a process, method, device, product or device comprising a series of steps or units does not necessarily have to be limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0021] For ease of understanding, the specific process of the embodiments of the present invention will be described below. Please refer to Figure 1Schematic diagram of a substation station-use microgrid system based on an electric energy router provided by an embodiment of the present invention. The system includes a traditional substation station-use power system, an electric energy router, a wind power and photovoltaic power generation system, and an energy storage system. Among them,

[0022] The traditional substation station-use power system includes an off-site power source, an in-station low-voltage bus, a station-use transformer, an ATS switching device, and a 380V bus. The off-site power source cooperates with the in-station low-voltage bus through the station-use transformer. The ATS switching device ensures power supply continuity, and the 380V bus supplies power to the station-use load;

[0023] The electric energy router is connected to each section of the 380V bus and has an AC-DC module and a flexible interconnection function;

[0024] The wind power and photovoltaic power generation system converts the generated alternating current through the AC-DC module of the electric energy router and then accesses the 380V bus. When the power generation is excessive, the excess electric energy is stored in the energy storage system; when the power generation is insufficient, the energy storage system releases electric energy to meet the demand of the station-use load;

[0025] The energy storage system is connected to the electric energy router, stores electric energy when the new energy power generation is excessive, and releases electric energy when the power generation is insufficient or during the peak of the station-use load, smoothing the fluctuations of the new energy power generation and stabilizing the power supply

[0026] In this embodiment, the traditional substation station-use power system is powered by the 1# station-use transformer, 2# station-use transformer, and 0# station-use transformer. The off-site power source is connected to the 0# station-use transformer through the 3DL switch, the in-station low-voltage section I bus is connected to the 1# station-use transformer through the 1DL switch, and the in-station low-voltage section II bus is connected to the 2# station-use transformer through the 2DL switch.

[0027] In this embodiment, the traditional substation station service power system includes 3 incoming switch cabinets for the station service power system and 8 feeder switch cabinets for the station service power system. The incoming switch cabinet 1 of the station service power system contains the incoming switch 11QF and the ATS switching device 1. The incoming switch cabinet 2 of the station service power system contains the incoming switches 12QF and 22QF. The incoming switch cabinet 3 of the station service power system contains the incoming switches 21QF and the ATS switching device 2. The incoming switch cabinets of the station service power system are the devices used to introduce power into the substation station service power system. Their main function is to connect the external power supply into the station and perform operations such as controlling, protecting, and monitoring the power supply. Generally, they include components such as incoming switches and switching devices. The incoming switches 11QF, 12QF, 21QF, and 22QF are the switching devices in the incoming switch cabinets of the station service power system, used to control the on and off of the corresponding power lines, playing the roles of connecting and disconnecting the circuit and cutting off the circuit in case of a fault to protect the equipment and lines. The ATS switching device, i.e., the automatic transfer switch electrical appliance, is mainly used for the automatic switching between two power sources. When one power source fails or loses power, it can quickly switch the load to the other normal power source to ensure the continuous power supply to the load and improve the reliability and stability of the power supply. The ATS switching device 1 and the ATS switching device 2 here are respectively used for the power source switching of different busbars. The No. 1 station service transformer, No. 2 station service transformer, and No. 0 station service transformer, i.e., the 1st, 2nd, and 0th station service transformers, are used to transform the high voltage of the substation into the low voltage suitable for the use of the equipment in the station and provide power for the station service power system. Different station service transformers are connected to the ATS switching device through the corresponding switches to provide different power inputs for the busbars.

[0028] In this embodiment, the No. 1 station service transformer is connected to one end of the ATS switching device 1 and the No. 2 station service transformer is connected to one end of the ATS switching device 2 through the 11QF switch and the 21QF switch respectively, and the No. 0 station service transformer is connected to the other ends of the ATS switching device 1 and the ATS switching device 2 through the 12QF switch and the 22QF switch respectively.

[0029] In this embodiment, the output end of the ATS switching device 1 is connected to the 380V I-section busbar, and the output end of the ATS switching device 2 is connected to the 380V II-section busbar.

[0030] In this embodiment, the 380V Section I busbar and the 380V Section II busbar are connected through the flexible interconnection module of the power router. The AC-DC modules of the power router are respectively connected to the 380V Section I busbar and the 380V Section II busbar. The power router can convert, control, and manage electric energy of different types and voltage levels, realizing flexible distribution and efficient transmission of electric energy, and playing a core regulation role in the substation's station-use microgrid system. The flexible interconnection module is an integral part of the power router, used to connect the 380V Section I busbar and the 380V Section II busbar, capable of realizing flexible transmission and allocation of power between the two busbars. When the load of one of the busbars changes or a fault occurs, it can quickly adjust the power flow direction and magnitude to ensure the stable operation of the system. The AC-DC module, namely the AC-DC conversion module, is an important part of the power router, which can convert AC electric energy into DC electric energy and vice versa, realizing the conversion of different types of electric energy to meet the needs of different power sources (such as photovoltaic, energy storage, etc.) and loads in the system. In this embodiment, it is respectively connected to the 380V Section I busbar and the 380V Section II busbar to promote electric energy interaction.

[0031] In this embodiment, the 380V Section I busbar and the 380V Section II busbar are also respectively connected to multiple station-use loads. Meanwhile, photovoltaic, wind power, and energy storage devices are connected to the 380V busbar through the power router.

[0032] In this embodiment, the feeder cabinets of the 8-sided station power supply system are divided into 4 feeder cabinets for the I-section bus and 4 feeder cabinets for the II-section bus according to the bus. The feeder cabinets for the I-section bus include the air switches for the power supply branches of the station loads 11CK, 12CK, and 13CK under the 380V I-section bus and the air switch 1JK for connecting to the energy router. The feeder cabinets for the II-section bus include the air switches for the power supply branches of the station loads 21CK, 22CK, and 23CK under the 380V II-section bus and the air switch 2JK for connecting to the energy router. The feeder cabinets of the station power supply system are devices used to distribute electric energy in the substation station power supply system. They distribute the electric energy from the bus to each station load branch and connect to devices such as the energy router, playing roles such as electric energy distribution, circuit control, and protection. The I-section bus and the II-section bus are the segments of the low-voltage bus in the substation, used to partition the power supply system for the convenience of electric energy distribution and management. Different sections of the bus can be connected to different power sources and loads respectively. The feeder cabinets for the I-section bus and the feeder cabinets for the II-section bus are the feeder cabinets connected under the I-section bus and the II-section bus respectively. The former is responsible for managing the electric energy distribution related to the I-section bus, and the latter is responsible for managing the electric energy distribution related to the II-section bus. The 380V I-section bus and the 380V II-section bus represent the I-section and II-section buses with a voltage level of 380 volts, which are the AC low-voltage buses in the station power supply system and provide 380V AC power for the station loads. 11CK, 12CK, 13CK, 21CK, 22CK, and 23CK are the identifiers of the station loads, representing different station load devices, such as some in-station lighting, ventilation, and control devices. These loads obtain electric energy from the bus through the corresponding power supply branch air switches. The power supply branch air switch, that is, the air switch of the power supply branch, is a circuit protection device that automatically cuts off the circuit in case of faults such as overload and short circuit in the circuit, playing a role in protecting the line and equipment. At the same time, it can also be used for circuit on-off operations under normal circumstances. 1JK and 2JK are the line identifiers connecting the corresponding bus and the energy router. 1JK connects the 380V I-section bus and the energy router, and 2JK connects the 380V II-section bus and the energy router. The air switch for connecting to the energy router is used to control the on-off of the circuit between the 1JK and 2JK lines and the energy router. It can cut off or connect the electrical connection between the bus and the energy router when needed and also has a certain circuit protection function. The air switches in the feeder cabinets for the I-section bus: Under the 380V I-section bus, the feeder cabinets for the I-section bus include the air switches for the power supply branches of the station loads 11CK, 12CK, and 13CK. These air switches are responsible for distributing electric energy to the corresponding station loads. At the same time, it also includes the air switch 1JK for connecting to the energy router, which is used to establish the electrical connection between the I-section bus and the energy router to achieve the transmission and interaction of electric energy. The air switches in the feeder cabinets for the II-section bus: Under the 380V II-section bus, the feeder cabinets for the II-section bus include the air switches for the power supply branches of the station loads 21CK, 22CK, and 23CK, undertaking the task of supplying power to the corresponding station loads.In addition, there is also an air switch for the 2JK to access the power router, whose function is to realize the power transmission and interaction between the section II bus and the power router.

[0033] Taking a 330 kV substation as an example, the substation is equipped with two station service transformers (1# and 2# station service transformers) and one standby station service transformer (0# station service transformer). The 1# station service transformer is connected from the in-station low-voltage section I bus, the 2# station service transformer is connected from the in-station low-voltage section II bus, and the 0# station service transformer is connected from an out-of-station 35 kV or 10 kV power source. The station service power system of the substation is powered by two station service transformers (1# and 2# station service transformers) and one standby station service transformer (0# station service transformer). The power supply method is that the 1# and 2# station service transformers respectively supply the 380V section I and II buses. The 0# station service transformer is connected to the 380V section I and II buses after being switched with the 1# and 2# station service transformers respectively through two sets of ATS switching devices, serving as the standby of the station service transformers (1# and 2# station service transformers). The station service power system includes 3 incoming switch cabinets for the station service power system and 8 feeder switch cabinets for the station service power system. The incoming switch cabinet 1 of the station service power system contains an incoming switch 11QF and an ATS switching device 1. The incoming switch cabinet 2 of the station service power system contains an incoming switch 12QF and an incoming switch 22QF. The incoming switch cabinet 3 of the station service power system contains an incoming switch 21QF and an ATS switching device 2. The two sets of ATS dual-power switching devices can accurately judge the abnormal voltage conditions of the power supply lines by real-time monitoring of the three-phase voltages of the three circuits, and control the ATS switching after a predetermined delay to realize the switching function between the station service transformers and ensure the normal power supply of the station service load. The feeder switch cabinets of the station service power system are divided into 4 feeder switch cabinets for the section I bus and 4 feeder switch cabinets for the section II bus according to the bus. The feeder switch cabinets for the section I bus contain the air switches of the power supply branch circuits of the station service loads such as 11CK, 12CK, and 13CK under the 380V section I bus and the air switch for the 1JK to access the power router. The feeder switch cabinets for the section II bus contain the air switches of the power supply branch circuits of the station service loads such as 21CK, 22CK, and 23CK under the 380V section II bus and the air switch for the 2JK to access the power router.

[0034] The power electronic router is a multi-energy DC coupling device that integrates the electrical control part of the DC microgrid based on the common DC bus technology and the flexible interconnection device based on the back-to-back converter into an integrated electrical control device, realizing functions such as the control of new energy power generation, grid connection control, flexible power interconnection between two AC systems, microgrid power control, and distribution protection, and connecting the microgrid system to the traditional substation station service system in a local way; multi-energy DC coupling means coupling various forms of energy (such as solar energy, wind energy, etc.) in a DC manner, enabling different energies to operate and interact synergistically on the DC side, facilitating unified control and management, and improving energy utilization efficiency; the DC microgrid is a small power generation and distribution system composed of distributed power sources, energy storage devices, energy conversion devices, related loads, and monitoring and protection devices, which can operate in parallel with the external power grid or operate independently. It conducts power transmission and distribution in DC form and has unique advantages in aspects such as new energy access and power quality; in the power system, the common DC bus technology shares the same DC bus for multiple power equipment or modules to conduct power transmission and distribution, and each device or module can interact and cooperate through this bus, facilitating the unified management and optimal control of energy; the back-to-back converter is a device composed of two converters connected through the DC side, which can realize the conversion and transmission of electric energy between different AC systems, can flexibly control the active power and reactive power, and is commonly used in fields such as high-voltage DC transmission and flexible AC transmission to improve the stability and controllability of the power system; the flexible interconnection device can flexibly control the transmission and distribution of electric power, can quickly adjust the power flow according to system requirements, improve the flexibility, stability, and reliability of the power system, and enhance the interconnection ability and cooperative operation ability between different power grids; through the flexible AC transmission technology or other flexible power equipment to achieve power interconnection between different power systems, it can flexibly adjust the magnitude and direction of power, improve the interconnection ability between power systems and the flexibility of power transmission, and enhance the stability and reliability of the system.

[0035] The photovoltaic power generation system consists of monocrystalline silicon battery modules, inverters, etc., and is connected to the power router through a circuit breaker. The wind power generation system consists of wind turbines and is connected to the power router through a circuit breaker. Energy storage refers to the process of storing energy through a medium or device and releasing it when needed. Energy storage systems can be divided into mechanical energy storage, electrical energy storage, electrochemical energy storage, thermal energy storage, and chemical energy storage. The application forms of mechanical energy storage include pumped-storage energy storage, compressed-air energy storage, and flywheel energy storage. Electrochemical energy storage mainly includes lithium-ion battery energy storage, lead-acid battery energy storage, and flow battery energy storage. The energy storage system in the substation adopts an electrochemical energy storage system, which mainly consists of a battery pack, a battery management system (BMS), an energy management system (EMS), a power conversion system (PCS), and other electrical equipment, and is connected to the power router through a circuit breaker. The coordinated operation of power generation, energy storage charging and discharging, and the power consumption end is realized through the automatic control of the power router, and green energy is used to supply the substation station service load. The power router is the center for controlling power distribution and protection. The central controller inside the power router is responsible for realizing system power flow control and algorithm protection to maximize the local utilization of clean energy.

[0036] The monocrystalline silicon battery module is the core component in the photovoltaic power generation system. It is composed of monocrystalline silicon solar cells connected in series or parallel, and converts solar energy into electrical energy through the photovoltaic effect, with characteristics such as high conversion efficiency and good stability; the inverter is used to convert the direct current generated by the solar cell module in the photovoltaic power generation system into alternating current for connection and use with the power grid or other alternating current load devices, and also has functions such as maximum power point tracking, overcurrent protection, and overvoltage protection; the circuit breaker is a switching electrical appliance that can connect and disconnect the circuit under normal and fault conditions. In the photovoltaic power generation system, wind power generation system, and energy storage system, it is used to control the on-off of the circuit and protect the equipment and lines. When faults such as overload and short circuit occur in the circuit, it can automatically cut off the circuit.

[0037] A battery pack is an assembly of multiple battery cells combined in series, parallel, or series-parallel configurations. It is the core component for storing electrical energy in an energy storage system, providing the necessary energy for the system. A battery management system is a system used to monitor, control, and manage the battery pack. Its main functions include battery state monitoring, battery charge and discharge control, battery fault diagnosis and protection, battery equalization management, etc., ensuring the safe and efficient operation of the battery pack and extending its service life. An energy management system is a system that comprehensively manages and schedules the energy of the energy storage system and the entire substation's microgrid system. According to the power generation, power consumption, and energy storage status of the system, it formulates a reasonable energy distribution strategy to achieve coordinated operation among power generation, energy storage charge and discharge, and the power consumption side, improving energy utilization efficiency and system stability. A power conversion system (PCS) is a power electronic device used to achieve bidirectional power conversion between the energy storage system and the power grid or other electrical equipment. It can convert the direct current output by the battery pack into alternating current and connect it to the power grid, or convert the alternating current from the power grid into direct current to charge the battery pack. At the same time, it can also control and regulate the power, frequency, phase, etc. of the electrical energy. A power router: In this system, it is the central device for controlling power distribution and protection. It can convert, control, and distribute electrical energy from different sources, enabling flexible interconnection and coordinated operation among power generation, energy storage, and electrical equipment. The central controller inside it is responsible for implementing system power flow control and algorithm protection.

[0038] Through the implementation of the above solutions, with multi-power source guarantee and flexible allocation of the power router, the system can still continuously supply power to the substation load in case of power source failure or equipment failure. The power router can flexibly convert and distribute electrical energy according to different working conditions and load demands, adapting to complex operating environments. The electrical energy generated by wind power generation and photovoltaic power generation systems can be consumed locally. The energy storage system effectively regulates the power supply and demand of electrical energy, reduces dependence on the traditional power grid, and improves energy utilization efficiency.

[0039] The above has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited by the above embodiments. The above embodiments and the descriptions in the specification are only preferred examples of the present invention and are not used to limit the present invention. Without departing from the spirit and scope of the present invention, the present invention will have various changes and improvements, and these changes and improvements all fall within the scope of the present invention claimed. The scope of protection claimed by the present invention is defined by the appended claims and their equivalents.

Claims

1. A microgrid system for a substation based on an electric energy router, characterized in that: The substation microgrid system based on the power router includes a traditional substation power system, a power router, a wind power generation system, a photovoltaic power generation system and an energy storage system, wherein: The traditional substation power system includes an off-site power supply, an on-site low-voltage bus, a station transformer, an ATS switch, and a 380V bus. The off-site power supply is coordinated with the on-site low-voltage bus through the station transformer. The ATS switch ensures power supply continuity, and the 380V bus supplies power to the station load. The power router connects the 380V busbars and has AC-DC modules and flexible interconnection functions; The AC power generated by the wind power generation and photovoltaic power generation systems is converted by the AC-DC module of the power router and then connected to the 380V bus. When there is excess power generation, the excess power is stored in the energy storage system; when there is insufficient power generation, the energy storage system releases power to meet the station load demand; The energy storage system is connected to the power router. It stores electricity when there is excess power generation from renewable energy and releases electricity when there is insufficient power generation or when the station load is at peak, thereby smoothing out fluctuations in renewable energy power generation and stabilizing power supply.

2. A microgrid system for a substation based on an electric energy router as claimed in claim 1, characterized in that: The traditional substation power system is powered by 1# station transformer, 2# station transformer and 0# station transformer. The external power supply is connected to 0# station transformer through a 3DL switch, the low-voltage section I bus in the station is connected to 1# station transformer through a 1DL switch, and the low-voltage section II bus in the station is connected to 2# station transformer through a 2DL switch.

3. A microgrid system for a substation based on an electric energy router as claimed in claim 2, characterized in that: The traditional substation power system includes 3 station power system incoming cabinets and 8 station power system feeder cabinets. The station power system incoming cabinet 1 contains an 11QF incoming switch and an ATS switching device 1. The station power system incoming cabinet 2 contains a 12QF incoming switch and a 22QF incoming switch. The station power system incoming cabinet 3 contains a 21QF incoming switch and an ATS switching device 2.

4. A microgrid system for a substation based on an electric energy router as claimed in claim 3, characterized in that: The 1# station transformer is connected to one end of the ATS switching device 1 and the 2# station transformer is connected to one end of the ATS switching device 2 through the 11QF switch, and the 2# station transformer is connected to the other end of the ATS switching device 1 and the ATS switching device 2 through the 21QF switch. The 0# station transformer is connected to the other end of the ATS switching device 1 and the ATS switching device 2 through the 12QF switch and the 22QF switch.

5. A microgrid system for a substation based on an electric energy router as claimed in claim 3, characterized in that: The output end of the ATS switching device 1 is connected to the 380V VI bus segment, and the output end of the ATS switching device 2 is connected to the 380V II bus segment.

6. A microgrid system for a substation based on an electric energy router as claimed in claim 5, characterized in that: The 380VI bus segment and the 380VII bus segment are connected via a flexible interconnection module of the power router, and the AC-DC module of the power router is connected to the 380VI bus segment and the 380VII bus segment respectively.

7. A microgrid system for a substation based on an electric energy router as claimed in claim 5, characterized in that: The 380VVI bus and 380VII bus are also connected to multiple station loads respectively. At the same time, photovoltaic, wind power and energy storage equipment are connected to the 380V bus through the power router.

8. A microgrid system for a substation based on an electric energy router as claimed in claim 3, characterized in that: The 8 station power system feeder cabinets are divided into 4 I-section bus feeder cabinets and 4 II-section bus feeder cabinets according to the busbar. The I-section bus feeder cabinet contains the power supply branch circuit breakers for the 11CK, 12CK, 13CK station loads under the 380V I-section bus and the circuit breaker 1JK connected to the power router. The II-section bus feeder cabinet contains the power supply branch circuit breakers for the 21CK, 22CK, 23CK station loads under the 380V II-section bus and the circuit breaker 2JK connected to the power router.

Images