WO2024001672A1 - Thermal power optical storage flexible networking system - Google Patents

Abstract

Disclosed is a thermal power optical storage flexible networking system, comprising: a thermal power plant unit comprising a 6 kV plant bus and used for performing power transmission on a power grid system; and a photovoltaic-energy storage-low voltage electric load microgrid unit comprising a 400 V comprehensive energy bus and used for performing power transmission on the thermal power plant unit by means of a soft switch unit voltage transformation unit. The high-voltage side of the soft switch unit voltage transformation unit is connected to the 6 kV plant bus, the low-voltage side of the soft switch unit voltage transformation unit is connected to the 400 V comprehensive energy bus, and the soft switch unit voltage transformation unit is used for providing a power transmission channel when the thermal power plant unit and the photovoltaic-energy storage-low voltage electric load microgrid unit perform power transmission.

Description

Thermal power, optical storage and flexible networking system

Cross-references to related applications

This application claims priority from Chinese Patent Application No. 2022107481933 filed in China on June 29, 2022, the entire content of which is incorporated herein by reference.

Technical field

The present disclosure relates to the field of power transmission technology, and specifically relates to a thermal power, optical storage and flexible networking system.

Background technique

With the development of science and technology, thermal power plants are transforming and upgrading into comprehensive energy load source supply enterprises. In related technologies, when a photovoltaic system is incorporated into a high-voltage bus system for thermal power plants as a load source, a corresponding access solution needs to be selected based on the access capacity. These solutions have one thing in common, that is, both the power supply and the load are connected to the high-voltage bus system used in thermal power plants. However, this will exceed the original design capacity of the busbar, which will require expansion of the interval. In addition, the short-circuit current exceeds the limit after large-capacity loads are connected, which requires large-scale transformation of the equipment in the high-voltage busbar system for thermal power plants. Secondly, the increase in equipment in the high-voltage busbar system for thermal power plants will lead to an increase in fault points, which will in turn lead to an increase in the probability of busbar failure.

Contents of the invention

Embodiments of the present disclosure provide a thermal power, optical and storage flexible networking system. The main purpose is to provide a thermal power, optical and storage flexible networking system with low equipment failure rate, flexible control method and high power supply reliability.

According to an embodiment of the present disclosure, a thermal power, photovoltaic and storage flexible networking system is provided, including: a thermal power plant unit, a soft switching unit transformer unit, and a photovoltaic-energy storage-low-voltage power load microgrid unit;

The thermal power plant unit includes a 6kV factory busbar, which is used for power transmission to the power grid system;

The photovoltaic-energy storage-low-voltage electric load microgrid unit includes a 400V integrated energy bus, which is used to transmit power to the thermal power plant unit through a soft switching unit transformer unit;

The high-voltage side of the soft-switching unit transformer unit is connected to the 6kV factory bus, and the low-voltage side of the soft-switching unit transformer unit is connected to the 400V comprehensive energy bus for use in the thermal power plant. When the unit and the photovoltaic-energy storage-low-voltage electric load microgrid unit perform power transmission, a power transmission channel is provided;

The soft switching unit transformer unit includes: a power transmission switch, a factory-used optical storage microgrid flexible networking SOP, an optical-storage microgrid grid-connected switch and a 400V/6kV transformer, wherein the factory-used optical storage microgrid flexible group The network SOP is a fully controlled power electronic device. The fully controlled power electronic device includes: a back-to-back voltage source converter with four-quadrant power control function to realize power transmission;

The 6kV factory busbar includes: 6kV factory A section busbar and 6kV factory B section busbar. The thermal power plant unit also includes: thermal power generator, thermal power unit main transformer, thermal power unit high transformer, 6kV factory busbar. Section A busbar grid-connected switch, 6kV factory section B busbar grid-connected switch, 6kV factory section A load grid-connected switch, 6kV factory section B load grid-connected switch, 6kV factory section A load and 6kV factory section B load ;

Wherein, the thermal power generator is connected to the main transformer of the thermal power unit and the high-voltage side of the high-voltage transformer of the thermal power unit. The low-voltage side A branch of the high-voltage transformer of the thermal power unit is connected to the grid through the 6kV factory A-section busbar. The switch is connected to the 6kV factory A-section bus, and the low-voltage side B branch of the high-power transformer of the thermal power unit is connected to the 6kV factory B-section bus through the 6kV factory B-section bus grid connection switch. The 6kV The factory A-section load is connected to the 6kV factory A-section busbar through the 6kV factory A-section load grid-connected switch, and the 6kV factory B-section load is connected to the 6kV factory B-section load grid-connected switch. The 6kV factory B section busbar;

The photovoltaic-energy storage-low-voltage power load microgrid unit also includes: a photovoltaic power generation unit, an energy storage unit and a comprehensive energy load unit; the photovoltaic power generation unit, the energy storage unit and the comprehensive energy load unit are all connected to the 400V integrated energy bus;

In response to the light intensity being not less than the intensity threshold and the stored energy of the energy storage unit being less than the first electricity threshold, the photovoltaic power generation unit performs power transmission to the energy storage unit and the comprehensive energy load unit;

In response to the illumination intensity being not less than the intensity threshold and the stored energy of the energy storage unit being not less than the first electricity threshold, the photovoltaic power generation unit generates electricity for the thermal power through the soft switching unit transformer unit. Factory units perform power transfer;

In response to the light intensity being less than the intensity threshold, and the energy storage capacity of the energy storage unit being not less than the second electricity threshold, the energy storage unit performs power transmission to the integrated energy load unit;

In response to the illumination intensity being less than the intensity threshold and the energy storage capacity of the energy storage unit being less than the second electricity threshold, the thermal power plant unit uses the soft switching unit transformer unit to convert the energy storage unit to unit for power transfer.

In one embodiment of the present disclosure, the 6kV factory bus includes: a 6kV factory A-section bus and a 6kV factory B-section bus;

Among them, the flexible networking SOP of the factory optical storage microgrid is connected to the 6kV factory B section busbar through the power transmission switch, and the flexible networking SOP of the factory optical storage microgrid passes through the optical storage microgrid. The grid-connected switch is connected to the high-voltage side of the 400V/6kV transformer, and the low-voltage side of the 400V/6kV transformer is connected to the 400V comprehensive energy bus.

In one embodiment of the present disclosure, the fully controlled power electronic device includes power electronic commutation components;

When the fully controlled power electronic device is working, it operates according to the preset power factor according to the real-time power adjustment demand of the electrical load;

or,

When the power electronic commutation components are working, they operate according to unit power factor.

In one embodiment of the present disclosure, the power electronic commutation component is an insulated gate bipolar transistor IGBT component.

In one embodiment of the present disclosure, the photovoltaic power generation unit includes: a photovoltaic power generation system grid-connected switch, a photovoltaic inverter and a photovoltaic panel;

Wherein, the photovoltaic panel is connected to the 400V comprehensive energy bus through the photovoltaic inverter and the photovoltaic power generation system grid connection switch.

In one embodiment of the present disclosure, the energy storage unit includes an energy storage system grid connection switch, an energy storage system PCS and an energy storage element;

Wherein, the energy storage element is connected to the 400V comprehensive energy bus through the energy storage system PCS and the energy storage system grid connection switch.

In one embodiment of the present disclosure, the integrated energy load unit includes an integrated energy load grid-connected switch and an integrated energy load;

Wherein, the comprehensive energy load is connected to the 400V comprehensive energy bus through the comprehensive energy load grid connection switch.

In summary, the thermal power, photovoltaic and storage flexible networking system proposed by one embodiment of the present disclosure includes: a thermal power plant unit, a soft switching unit transformer unit, and a photovoltaic-energy storage-low-voltage power load microgrid unit; the thermal power unit The power plant unit includes a 6kV factory bus, which is used to transmit power to the power grid system; the photovoltaic-energy storage-low-voltage power load microgrid unit includes a 400V integrated energy bus, which is used to transmit power to all power grids through the soft switching unit transformer unit. The thermal power plant unit performs power transmission; the high-voltage side of the soft-switching unit transformer unit is connected to the 6kV factory bus, and the low-voltage side of the soft-switching unit transformer unit is connected to the 400V comprehensive energy bus , used to provide a power transmission channel when the thermal power plant unit and the photovoltaic-energy storage-low-voltage electric load microgrid unit perform power transmission; the soft switching unit transformer unit includes: a power transmission switch, Flexible networking SOP for factory-used optical storage microgrid, grid-connected switch for optical storage microgrid and 400V/6kV transformer. The flexible networking SOP for factory-used optical storage microgrid is a fully controlled power electronic device. The fully controlled It is a power electronic device, including: back-to-back voltage source converter, with four-quadrant power control function to realize power transmission. In the embodiment of the present disclosure, the photovoltaic-energy storage-low-voltage electric load microgrid unit and the soft switching unit transformer unit are incorporated into the high-voltage busbar system for thermal power plants as part of the flexible distribution network, which will not exceed the original requirements of the thermal power unit. The original design capacity of the busbar, so there is no need to extend the interval. In addition, the photovoltaic-energy storage-low-voltage power load microgrid unit is connected to the thermal power plant unit through the soft switching unit transformer unit, which can reduce the number of photovoltaic-energy storage-low-voltage power load microgrid units integrated into the thermal power plant. The high-voltage busbar system is an additional equipment used in the high-voltage busbar system of thermal power plants, which can reduce the equipment failure rate. In addition, the soft switching unit transformer unit connects the photovoltaic-energy storage-low-voltage electric load microgrid unit and the thermal power plant unit, which can also reduce the short-circuit current after connecting a large-capacity load, thereby reducing the impact on the thermal power plant. The extent to which equipment in the high-voltage busbar system has been modified. Moreover, the thermal power, optical storage and flexible networking system has flexible control methods and high power supply reliability.

Additional aspects and advantages of the disclosure will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the disclosure.

Description of drawings

The above and/or additional aspects and advantages of the present disclosure will become apparent and readily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

Figure 1 is a schematic structural diagram of a thermal power, optical and storage flexible networking system provided by an embodiment of the present disclosure;

Figure 2 is a schematic structural diagram of a unit for a thermal power plant provided by an embodiment of the present disclosure;

Figure 3 is a schematic structural diagram of a soft switching unit transformer unit provided by an embodiment of the present disclosure;

Figure 4 is a schematic structural diagram of a photovoltaic-energy storage-low-voltage electric load microgrid unit provided by an embodiment of the present disclosure;

Figure 5 is a schematic structural diagram of a photovoltaic power generation unit provided by an embodiment of the present disclosure;

Figure 6 is a schematic structural diagram of an energy storage unit provided by an embodiment of the present disclosure;

Figure 7 is a schematic structural diagram of a comprehensive energy load unit provided by an embodiment of the present disclosure.

Explanation of reference symbols: 1—thermal power plant unit; 2—soft switching unit transformer unit; 3—photovoltaic-energy storage-low-voltage power load microgrid unit;

1-1—Thermal power generator; 1-2—Thermal power unit main transformer; 1-3—Thermal power unit high plant transformer; 1-4—6kV plant section A busbar grid connection switch; 1-5—6kV plant section B Busbar grid-connected switch; 1-6-6kV factory use section A busbar; 1-7-6kV factory use section B busbar; 1-8-6kV factory use section A load grid-connected switch; 1-9-6kV factory use section B Load grid-connected switch; 1-10-6kV factory A-section load; 1-11-6kV factory B-section load;

2-1—Power transmission switch; 2-2—Factory optical storage microgrid flexible networking SOP; 2-3—Optical storage microgrid grid connection switch; 2-4—400V/6kV transformer;

3-1—400V comprehensive energy bus; 3-2—Photovoltaic power generation unit; 3-3—Energy storage unit; 3-4—Comprehensive energy load unit;

3-2-1 Photovoltaic power generation system grid connection switch; 3-2-2—Photovoltaic inverter; 3-2-3—Photovoltaic panels;

3-3-1—Energy storage system grid connection switch; 3-3-2—Energy storage system PCS; 3-3-3—Energy storage components;

3-4-1—Comprehensive energy load grid connection switch; 3-4-2—Comprehensive energy load.

Detailed ways

Embodiments of the present disclosure are described in detail below, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the drawings are exemplary and are only used to explain the present disclosure and are not to be construed as limitations of the present disclosure. On the contrary, the disclosed embodiments include all changes, modifications and equivalents falling within the spirit and scope of the appended claims.

The present disclosure will be described in detail below with reference to specific embodiments.

Figure 1 is a schematic structural diagram of a thermal power, optical and storage flexible networking system provided by an embodiment of the present disclosure.

As shown in Figure 1, an embodiment of the present disclosure provides a thermal power, photovoltaic and storage flexible networking system, including: a thermal power plant unit 1, a soft switching unit transformer unit 2, and a photovoltaic-energy storage-low-voltage power load microgrid. Unit 3;

The thermal power plant unit 1 includes a 6kV factory busbar, which is used for power transmission to the power grid system;

The photovoltaic-energy storage-low-voltage electric load microgrid unit 3 includes a 400V comprehensive energy bus 3-1, which is used to transmit power to the thermal power plant unit 1 through the soft switching unit transformer unit 2;

The high-voltage side of the soft-switching unit transformer unit 2 is connected to the 6kV factory bus, and the low-voltage side of the soft-switching unit transformer unit 2 is connected to the 400V integrated energy bus 3-1, which is used in unit 1 of the thermal power plant and photovoltaic-storage When the low-voltage electric load microgrid unit 3 transmits power through the soft switching unit transformer unit 2, it provides a power transmission channel.

According to some embodiments, the thermal power, optical and storage flexible networking system also includes an optical and storage microgrid control center. The optical storage microgrid control center is used to control the power transmission size, power transmission form and power transmission direction of the soft switching unit transformer unit 2.

In some embodiments, when the light-storage microgrid control center controls the soft switching unit transformer unit 2, an energy balance control method is used to achieve independent decoupling of active power and reactive power.

According to some embodiments, distribution networks transformed using flexible power electronics technology are an important trend and can effectively solve some bottleneck problems in the development of traditional distribution networks. Advanced power electronics technology can build a flexible, reliable, and efficient distribution network, which can not only improve the power quality, reliability, and operating efficiency of the distribution system, but also cope with the volatility of traditional loads and proportional renewable energy.

In some embodiments, the embodiments of the present disclosure can not only improve The reliability of factory systems can also improve the economics and scalability of photovoltaic and integrated energy load access, and can also separate traditional power generation from diversified operations. In addition, the photovoltaic-energy storage-low-voltage electric load microgrid unit 3 and the soft switching unit transformer unit 2 are integrated into the high-voltage busbar system of the thermal power plant as part of the flexible distribution network, and will not exceed the original busbar of the thermal power unit. The original design capacity does not require expansion intervals.

In the embodiment of the present disclosure, FIG. 2 is a schematic structural diagram of a unit for a thermal power plant provided by the embodiment of the present disclosure. As shown in Figure 2, the 6kV factory busbar includes: 6kV factory A-section busbar 1-6 and 6kV factory B-section busbar 1-7. The thermal power plant unit 1 also includes: thermal power generator 1-1, thermal power unit Main transformer 1-2, thermal power unit high plant transformer 1-3, 6kV plant section A bus grid-connected switch 1-4, 6kV plant section B busbar grid-connected switch 1-5, 6kV plant section A load grid-connected switch 1-8, 6kV factory B section load grid connection switch 1-9, 6kV factory A section load 1-10 and 6kV factory B section load 1-11;

Among them, the thermal power generator 1-1 is connected to the high-voltage side of the main transformer 1-2 of the thermal power unit and the high-voltage transformer 1-3 of the thermal power unit. The low-voltage side A branch of the high-voltage power transformer 1-3 of the unit is connected to the 6kV factory A-section bus 1-6 through the 6kV factory A-section bus grid connection switch 1-4, and the low-voltage side B branch of the thermal power unit high-voltage power transformer 1-3 Connect to the 6kV factory B-section busbar 1-7 through the 6kV factory B-section busbar grid-connected switch 1-5, and the 6kV factory A-section load 1-10 is connected to 6kV through the 6kV factory A-section load grid-connected switch 1-8 The factory A-section busbars 1-6 and the 6kV factory B-section loads 1-11 are connected to the 6kV factory B-section busbars 1-7 through the 6kV factory B-section load grid connection switch 1-9.

According to some embodiments, the thermal power generator 1-1 is connected to the power grid system through the thermal power unit main transformer 1-2. Furthermore, the thermal power generator 1-1 can transmit power to the power grid system through the thermal power unit main transformer 1-2.

According to some embodiments, the high-voltage factory transformer 1-3 of the thermal power unit refers to a high-voltage factory transformer connected to the outlet of the thermal power generator 1-1 and used to step down the voltage and supply power to the thermal power plant itself. For example, the high-voltage transformer 1-3 of the thermal power unit can reduce the 20kV voltage output by the thermal power generator 1-1 to 6kV.

In some embodiments, by closing the 6kV factory A-section load grid connection switch 1-8, the 6kV factory A-section busbar 1-6 can supply power to the 6kV factory A-section load 1-10. By closing the 6kV factory B section load grid connection switch 1-9, the 6kV factory B section busbar 1-7 can supply power to the 6kV factory B section load 1-11.

In the embodiment of the present disclosure, the 6kV factory busbar includes: 6kV factory A-section busbar 1-6 and 6kV factory B-section busbar 1-7. FIG. 3 is a schematic structural diagram of a soft switching unit transformer unit provided by an embodiment of the present disclosure. As shown in Figure 3, the soft switching unit transformer unit 2 includes: power transmission switch 2-1, factory optical storage microgrid flexible networking SOP2-2, optical storage microgrid grid-connected switch 2-3 and 400V/6kV transformer 2-4;

Among them, the flexible networking SOP2-2 of the factory optical storage microgrid is connected to the 6kV factory B section busbar 1-7 through the power transmission switch 2-1. The grid-connected switch 2-3 is connected to the high-voltage side of the 400V/6kV transformer 2-4, and the low-voltage side of the 400V/6kV transformer 2-4 is connected to the 400V comprehensive energy bus 3-1.

According to some embodiments, the soft switching unit transformer unit 2 can realize 400V/6kV transformer through the 400V/6kV transformer 2-4. SOP commutation can also be achieved through the factory optical storage microgrid flexible networking SOP2-2.

According to some embodiments, the factory optical storage microgrid flexible networking SOP2-2 can be used as a flexible, reliable, and efficient current conversion device. The flexible networking SOP2-2 of the photovoltaic and storage microgrid of this plant can not only improve the quality of the power sent out by the photovoltaic-energy storage-low-voltage power load microgrid unit 3, but also realize the direct connection of the thermal power plant unit 1 to the photovoltaic-energy storage- The low-voltage electric load in the low-voltage electric load microgrid unit 3 delivers power reliably. Therefore, the power quality, reliability and operating efficiency of the thermal power, photovoltaic and storage flexible networking system can be improved, and it can also cope with the volatility of traditional loads and proportional renewable energy.

In this disclosed embodiment, the factory optical storage microgrid flexible networking SOP2-2 is a fully controlled power electronic device.

According to some embodiments, a fully controlled power electronic device refers to a power electronic device that can be controlled to be turned on and turned off through a control signal.

In some embodiments, when the factory optical storage microgrid flexible networking SOP2-2 is a fully controllable power electronic device, it has the characteristics of two-way flow of electric energy, continuous controllable power, and flexible control methods. Can replace the high-voltage busbar system used in thermal power plants Some traditional tie switches in the factory power generation-energy storage system can realize accurate, fast and flexible control of the active power and reactive power of the connected feeders, and can realize the function of optimizing the voltage of the factory power generation-energy storage system.

In some embodiments, when the factory-used optical storage microgrid flexible networking SOP2-2 is a fully controlled power electronic device, the factory-used optical storage microgrid flexible networking SOP2-2 can use a back-to-back voltage source inverter.

In some embodiments, back-to-back refers to a control method. The characteristic of back-to-back is that among two associated devices (or two parts of one device), the control purpose of one device is to adapt to the input, and the control purpose of the other device is to adapt to the output.

In some embodiments, when the factory optical storage microgrid flexible networking SOP2-2 adopts a back-to-back voltage source inverter, the back-to-back voltage source inverter has a four-quadrant power control function, and the factory optical storage microgrid flexible group The power between the two ports of the network SOP2-2 exhibits bidirectional flow characteristics. The topology of the two ports of the factory optical storage microgrid flexible networking SOP2-2 is completely symmetrical.

In some embodiments, the power response time corresponding to the four-quadrant power control function is milliseconds.

In some embodiments, when the thermal power plant unit 1 and the photovoltaic-energy storage-low-voltage electrical load microgrid unit 3 perform power transmission through the soft switching unit transformer unit 2, the power transmission can be performed in a power four-quadrant operation mode.

In the embodiment of the present disclosure, the components used in the fully controlled power electronic device may be power electronic commutation components. At this time, when the fully controlled power electronic device is working, the fully controlled power electronic device can operate according to the preset power factor according to the real-time power adjustment demand of the electrical load. Or, when the power electronic commutation component is working, it operates according to unit power factor.

According to some embodiments, power electronic commutation components refer to components used for commutation. The power electronic commutation components include but are not limited to gate turn-off thyristors, power field effect transistors, insulated gate bipolar transistors (IGBT), etc.

According to some embodiments, power factor (PF), also known as power factor, is a unique physical quantity in AC power systems. It is the ratio of the effective power consumed by a load to its apparent power. It is an infinite value between 0 and 1. Dimension quantity.

In some embodiments, unity power factor refers to the power factor when the power factor is equal to 1.

In the embodiment of the present disclosure, the power electronic commutation component is an insulated gate bipolar transistor IGBT component.

According to some embodiments, the power electronic commutation components used in the factory-based optical storage microgrid flexible networking SOP2-2 are IGBT components. Since IGBT components are high-power and high-frequency components, and IGBT components can increase the maximum short circuit The current does not exceed 1.5 times its rated current, and the protection judgment logic is simple and efficient. Therefore, the transmission efficiency and transmission effect of the thermal power plant unit 1 and the photovoltaic-energy storage-low-voltage electric load microgrid unit 3 through the soft switching unit transformer unit 2 can be improved.

In the embodiment of the present disclosure, FIG. 4 is a schematic structural diagram of a photovoltaic-energy storage-low-voltage electric load microgrid unit provided by the embodiment of the present disclosure. As shown in Figure 4, the photovoltaic-energy storage-low-voltage power load microgrid unit 3 also includes: photovoltaic power generation unit 3-2, energy storage unit 3-3 and comprehensive energy load unit 3-4; photovoltaic power generation unit 3-2 , energy storage unit 3-3 and comprehensive The energy load units 3-4 are all connected to the 400V integrated energy bus 3-1;

In response to the light intensity being not less than the intensity threshold and the stored electricity of the energy storage unit 3-3 being less than the first electricity threshold, the photovoltaic power generation unit 3-2 performs power transmission to the energy storage unit 3-3 and the comprehensive energy load unit 3-4;

In response to the light intensity being not less than the intensity threshold, and the stored electricity of the energy storage unit 3-3 being not less than the first electricity threshold, the photovoltaic power generation unit 3-2 performs power transmission to the thermal power plant unit 1 through the soft switching unit transformer unit 2 ;

In response to the light intensity being less than the intensity threshold, and the stored power of the energy storage unit 3-3 being not less than the second power threshold, the energy storage unit 3-3 performs power transmission to the comprehensive energy load unit 3-4;

In response to the light intensity being less than the intensity threshold and the stored electricity of the energy storage unit 3-3 being less than the second electricity threshold, the thermal power plant unit 1 transmits power to the energy storage unit 3-3 through the soft switching unit transformer unit 2.

According to some embodiments, the first power threshold refers to a threshold used to determine whether the photovoltaic power generation unit 3-2 can output excess power when the light intensity is not less than the intensity threshold. The first power threshold does not specifically refer to a fixed threshold. For example, the first power threshold may be the total power storage value of the energy storage unit 3-3. The first power threshold value may also be 90% of the total power storage value of the energy storage unit 3-3.

According to some embodiments, the second power threshold refers to when the light intensity is less than the intensity threshold, and is used to determine whether the thermal power plant unit 1 needs to transmit power to the energy storage unit 3-3 through the soft switching unit transformer unit 2. threshold. The second power threshold does not specifically refer to a fixed threshold. For example, the second power threshold may be 5% of the total power storage value of the energy storage unit 3-3. The second power threshold value may also be 10% of the total power storage value of the energy storage unit 3-3.

According to some embodiments, an energy storage unit 3-3 is provided in the photovoltaic-energy storage-low-voltage electric load microgrid unit 3, which can not only improve the stability of photovoltaic power supply, but also establish voltage through the energy storage unit 3-3 to drive photovoltaic power generation. Network, finally achieving black start of thermal power units.

In some embodiments, in response to a power outage of the thermal power unit in the thermal power plant unit 1, in order to achieve a black start of the thermal power unit, the voltage of the 400V integrated energy bus 3-1 can be maintained at 400V through the energy storage unit 3-3. Furthermore, through the photovoltaic power generation unit 3-2 stably building pressure and starting, the electric energy is sent back to the thermal power plant unit 1 to drive the factory auxiliary machinery to start. Finally, black start of thermal power units was achieved.

In the embodiment of the present disclosure, FIG. 5 is a schematic structural diagram of a photovoltaic power generation unit provided by the embodiment of the present disclosure. As shown in Figure 5, the photovoltaic power generation unit 3-2 includes: photovoltaic power generation system grid-connected switch 3-2-1, photovoltaic inverter 3-2-2 and photovoltaic panel 3-2-3;

Among them, the photovoltaic panel 3-2-3 is connected to the 400V comprehensive energy bus 3-1 through the photovoltaic inverter 3-2-2 and the photovoltaic power generation system grid connection switch 3-2-1.

According to some embodiments, the photovoltaic panel 3-2-3 can convert light energy into electrical energy, and transmit the converted electrical energy to the 400V integrated energy bus 3-1 through the photovoltaic inverter 3-2-2.

In the embodiment of the present disclosure, FIG. 6 is a schematic structural diagram of an energy storage unit provided by the embodiment of the present disclosure. As shown in Figure 6 As shown, the energy storage unit 3-3 includes the energy storage system grid connection switch 3-3-1, the energy storage system PCS3-3-2 and the energy storage component 3-3-3;

Among them, the energy storage component 3-3-3 is connected to the 400V comprehensive energy bus 3-1 through the energy storage system PCS3-3-2 and the energy storage system grid connection switch 3-3-1.

According to some embodiments, the energy storage element 3-3-3 refers to a power source that can be flexibly charged and discharged. The energy storage element 3-3-3 can dynamically absorb and release energy in the photovoltaic-energy storage-low-voltage electric load microgrid unit 3, and because of its fast response and flexible control characteristics, the energy storage element 3-3-3 It has irreplaceable advantages in maintaining grid-side frequency stability of the photovoltaic-energy storage-low-voltage power load microgrid unit 3.

In some embodiments, the energy storage element 3-3-3 can exchange electrical energy with the 400V integrated energy bus 3-1 through the energy storage system PCS3-3-2.

In some embodiments, when installing the energy storage component 3-3-3, the energy storage component 3-3-3 can be connected to the DC side of the grid-connected inverter of the distributed power point as a basis for regulating the load.

In the embodiment of the present disclosure, FIG. 7 is a schematic structural diagram of an integrated energy load unit provided by the embodiment of the present disclosure. As shown in Figure 7, the comprehensive energy load unit 3-4 includes a comprehensive energy load grid-connected switch 3-4-1 and a comprehensive energy load 3-4-2;

Among them, the comprehensive energy load 3-4-2 is connected to the 400V comprehensive energy bus 3-1 through the comprehensive energy load grid-connected switch 3-4-1.

According to some embodiments, the electric energy of the comprehensive energy load 3-4-2 comes from the 400V comprehensive energy bus 3-1.

According to some embodiments, in response to the normal operation of the photovoltaic-energy storage-low-voltage electricity load microgrid unit 3, if the light intensity is not less than the intensity threshold, and the stored electricity of the energy storage unit 3-3 is less than the first electricity threshold, the photovoltaic power generation Unit 3-2 is full. Furthermore, the photovoltaic power generation unit 3-2 can supply power to the comprehensive energy load 3-4-2. At the same time, the energy storage element 3-3-3 can also absorb electrical energy.

In some embodiments, in response to the normal operation of the photovoltaic-energy storage-low-voltage power load microgrid unit 3, if the light intensity is not less than the intensity threshold, and the stored power of the energy storage unit 3-3 is not less than the first power threshold, then The excess electric energy output by the photovoltaic power generation unit 3-2 can be fed back to the thermal power plant unit 1 through the soft switching unit transformer unit 2. Furthermore, the power consumption rate of the plant can be reduced and the economic benefits of thermal power units can be improved.

In some embodiments, in response to the light intensity being less than the intensity threshold and the stored electricity of the energy storage unit 3-3 being not less than the second electricity threshold, the photovoltaic power generation unit 3-2 stops operating and the energy storage element 3-3-3 starts to discharge. , and supplies power to the comprehensive energy load 3-4-2.

In some embodiments, in response to the light intensity being less than the intensity threshold, and the stored power of the energy storage unit 3-3 not being less than the second power threshold, and the power of the energy storage element 3-3-3 being insufficient, the thermal power plant unit 1 also The comprehensive energy load 3-4-2 can be supplied with power through the soft switching unit transformer unit 2.

In summary, the thermal power, optical and storage flexible networking system proposed in the embodiment of the present disclosure includes: thermal power plant unit 1, soft Switch unit transformer unit 2 and photovoltaic-energy storage-low-voltage power load microgrid unit 3; thermal power plant unit 1 includes a 6kV factory busbar for power transmission to the power grid system; photovoltaic-energy storage-low-voltage power load microgrid unit 3 The load microgrid unit 3 includes a 400V comprehensive energy bus 3-1, which is used to transmit power to the thermal power plant unit 1 through the soft switching unit transformer unit 2; the high voltage side of the soft switch unit transformer unit 2 is connected to 6kV Factory bus, the low voltage side of the soft switching unit transformer unit 2 is connected to the 400V comprehensive energy bus 3-1 for power transmission between the thermal power plant unit 1 and the photovoltaic-energy storage-low-voltage load microgrid unit 3 When, a power transmission channel is provided. The embodiment of the present disclosure incorporates the photovoltaic-energy storage-low-voltage electric load microgrid unit 3 and the soft switching unit transformer unit 2 as part of the flexible distribution network into the high-voltage bus system of the thermal power plant, without exceeding the original requirements of the thermal power unit. The original design capacity of the factory busbar, so there is no need to extend the interval. In addition, the photovoltaic-energy storage-low voltage power load microgrid unit 3 is connected to the thermal power plant unit 1 through the soft switching unit transformer unit 2, which can reduce the number of photovoltaic-energy storage-low-voltage power load microgrid unit 3. When added to the high-voltage bus system of thermal power plants, the equipment failure rate can be reduced. In addition, the photovoltaic-energy storage-low-voltage electric load microgrid unit 3 is connected to the thermal power plant unit 1 through the soft switching unit transformer unit 2, which can also reduce the short-circuit current after connecting a large-capacity load, thereby reducing the impact on the load. The extent to which equipment in the high-voltage busbar system of thermal power plants has been modified. Moreover, the thermal power, optical storage and flexible networking system has flexible control methods and high power supply reliability.

It should be noted that in the description of the present disclosure, the terms "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. Furthermore, in the description of the present disclosure, "plurality" means two or more unless otherwise specified.

Any process or method descriptions in flowcharts or otherwise described herein may be understood to represent modules, segments, or portions of code that include one or more executable instructions for implementing the specified logical functions or steps of the process. , and the scope of the preferred embodiments of the present disclosure includes additional implementations in which functions may be performed out of the order shown or discussed, including in a substantially simultaneous manner or in the reverse order, depending on the functionality involved, which shall It should be understood by those skilled in the art to which embodiments of the present disclosure belong.

It should be understood that various parts of the present disclosure may be implemented in hardware, software, firmware, or combinations thereof. In the above embodiments, various steps or methods may be implemented in software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if it is implemented in hardware, as in another embodiment, it can be implemented by any one or a combination of the following technologies known in the art: a logic gate circuit with a logic gate circuit for implementing a logic function on a data signal. Discrete logic circuits, application specific integrated circuits with suitable combinational logic gates, programmable gate arrays (PGA), field programmable gate arrays (FPGA), etc.

Those of ordinary skill in the art can understand that all or part of the steps involved in implementing the methods of the above embodiments can be completed by instructing relevant hardware through a program. The program can be stored in a computer-readable storage medium. The program can be stored in a computer-readable storage medium. When executed, one of the steps of the method embodiment or a combination thereof is included.

In addition, each functional unit in various embodiments of the present disclosure may be integrated into one processing module, each unit may exist physically alone, or two or more units may be integrated into one module. The above integrated modules can be implemented in the form of hardware or software function modules. If the integrated module is implemented in the form of a software function module and sold or used as an independent product, it can also be stored in a computer-readable storage medium.

The storage media mentioned above can be read-only memory, magnetic disks or optical disks, etc.

In the description of this specification, reference to the terms "one embodiment," "some embodiments," "an example," "specific examples," or "some examples" or the like means that specific features are described in connection with the embodiment or example. , structures, materials, or features are included in at least one embodiment or example of the present disclosure. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

Although the embodiments of the present disclosure have been shown and described above, it can be understood that the above-mentioned embodiments are illustrative and should not be construed as limitations of the present disclosure. Those of ordinary skill in the art can make modifications to the above-mentioned embodiments within the scope of the present disclosure. The embodiments are subject to changes, modifications, substitutions and variations.

Claims (7)

1. A thermal power, photovoltaic and storage flexible networking system, which is characterized by including: a thermal power plant unit, a soft switching unit transformer unit and a photovoltaic-energy storage-low-voltage power load microgrid unit;

   The thermal power plant unit includes a 6kV factory busbar, which is used for power transmission to the power grid system;

   The photovoltaic-energy storage-low-voltage electric load microgrid unit includes a 400V integrated energy bus, which is used to transmit power to the thermal power plant unit through a soft switching unit transformer unit;

   The high-voltage side of the soft-switching unit transformer unit is connected to the 6kV factory bus, and the low-voltage side of the soft-switching unit transformer unit is connected to the 400V comprehensive energy bus for use in the thermal power plant unit. When performing power transmission with the photovoltaic-energy storage-low-voltage electric load microgrid unit, provide a power transmission channel;

   The soft switching unit transformer unit includes: a power transmission switch, a factory-used optical storage microgrid flexible networking SOP, an optical-storage microgrid grid-connected switch and a 400V/6kV transformer, wherein the factory-used optical storage microgrid flexible group The network SOP is a fully controlled power electronic device. The fully controlled power electronic device includes: a back-to-back voltage source converter with four-quadrant power control function to realize power transmission;

   The 6kV factory busbar includes: 6kV factory A section busbar and 6kV factory B section busbar. The thermal power plant unit also includes: thermal power generator, thermal power unit main transformer, thermal power unit high transformer, 6kV factory busbar. Section A busbar grid-connected switch, 6kV factory section B busbar grid-connected switch, 6kV factory section A load grid-connected switch, 6kV factory section B load grid-connected switch, 6kV factory section A load and 6kV factory section B load ;

   Wherein, the thermal power generator is connected to the main transformer of the thermal power unit and the high-voltage side of the high-voltage transformer of the thermal power unit, and the low-voltage side A branch of the high-voltage transformer of the thermal power unit is connected to the grid through the 6kV factory A-section busbar. The switch is connected to the 6kV factory A-section bus, and the low-voltage side B branch of the high-power transformer of the thermal power unit is connected to the 6kV factory B-section bus through the grid-connected switch of the 6kV factory B-section bus. The 6kV The factory A-section load is connected to the 6kV factory A-section busbar through the 6kV factory A-section load grid-connected switch, and the 6kV factory B-section load is connected to the 6kV factory B-section load grid-connected switch. The 6kV factory B section busbar;

   The photovoltaic-energy storage-low-voltage power load microgrid unit also includes: a photovoltaic power generation unit, an energy storage unit and a comprehensive energy load unit; the photovoltaic power generation unit, the energy storage unit and the comprehensive energy load unit are all connected to the 400V integrated energy bus;

   In response to the light intensity being not less than the intensity threshold and the stored energy of the energy storage unit being less than the first electricity threshold, the photovoltaic power generation unit performs power transmission to the energy storage unit and the comprehensive energy load unit;

   In response to the illumination intensity being not less than the intensity threshold and the stored energy of the energy storage unit being not less than the first electricity threshold, the photovoltaic power generation unit generates electricity for the thermal power through the soft switching unit transformer unit. Factory units perform power transfer;

   In response to the light intensity being less than the intensity threshold, and the energy storage capacity of the energy storage unit being not less than the second electricity threshold, the energy storage unit performs power transmission to the integrated energy load unit;

   In response to the illumination intensity being less than the intensity threshold and the energy storage capacity of the energy storage unit being less than the second electricity threshold, the thermal power plant unit uses the soft switching unit transformer unit to convert the energy storage unit to unit for power transfer.
2. The thermal power, optical and storage flexible networking system according to claim 1, wherein the 6kV factory busbar includes: a 6kV factory A-section busbar and a 6kV factory B-section busbar;

   Among them, the flexible networking SOP of the factory optical storage microgrid is connected to the 6kV factory B section busbar through the power transmission switch, and the flexible networking SOP of the factory optical storage microgrid passes through the optical storage microgrid. The grid-connected switch is connected to the high-voltage side of the 400V/6kV transformer, and the low-voltage side of the 400V/6kV transformer is connected to the 400V comprehensive energy bus.
3. The thermal power, light and storage flexible networking system according to claim 2, wherein the fully controlled power electronic device includes power electronic commutation components;

   When the fully controlled power electronic device is working, it operates according to the preset power factor according to the real-time power adjustment demand of the electrical load;

   or,

   When the power electronic commutation components are working, they operate according to unit power factor.
4. The thermal power, light and storage flexible networking system according to claim 3, wherein the power electronic commutation components are insulated gate bipolar transistor IGBT components.
5. The thermal power, light and storage flexible networking system according to claim 1, wherein the photovoltaic power generation unit includes: a photovoltaic power generation system grid connection switch, a photovoltaic inverter and a photovoltaic panel;

   Wherein, the photovoltaic panel is connected to the 400V comprehensive energy bus through the photovoltaic inverter and the photovoltaic power generation system grid connection switch.
6. The thermal power and optical storage flexible networking system according to claim 1, wherein the energy storage unit includes an energy storage system grid connection switch, an energy storage system PCS and an energy storage element;

   Wherein, the energy storage element is connected to the 400V comprehensive energy bus through the energy storage system PCS and the energy storage system grid connection switch.
7. The thermal power, optical and storage flexible networking system according to claim 1, wherein the comprehensive energy load unit includes a comprehensive energy load grid-connected switch and a comprehensive energy load;

   Wherein, the comprehensive energy load is connected to the 400V comprehensive energy bus through the comprehensive energy load grid connection switch.