10kV energy router reconstruction-based power supply system for transformer substation and control method

Abstract

The invention discloses a 10kV energy router reconstruction-based power supply system for a transformer substation, which comprises an energy router, anflexible alternating current power supply system, a flexible direct current power supply system and a flexible communication power supply system, whereinthe energy router is composed of a bidirectional AC / DC electronic solid-state transformer, a unidirectional DC / DC photovoltaic cell array interface circuit and a bidirectional DC / DC energy storage cell array interface circuit, one end of the bidirectional AC / DC electronic solid-state transformer is connected with a power grid interface, and the other end is connected with aDC bus bar; the unidirectional DC / DC photovoltaic cell array interface circuit and the bidirectional DC / DC energy storage cell array interface circuit are connected with the DC bus bar; the flexible alternating current power supply system is connected with a DC bus bar led out from the energy router; the flexible direct current power supply system is connected with a DC bus bar led out from the energy router; and the flexible communication power supply system is connected with the DC bus bar led out from the energy router. The problem that safe and reliable operation of a power grid is affected after large-scale photovoltaic and energy storage access of a transformer substation is solved, and meanwhile, the design of a station power supply system is optimized.

Description

technical field [0001] The invention relates to the technical field of flexible power supplies for substations, in particular to a power supply system and control method for substations reconfigured based on a 10kV energy router. Background technique [0002] The existing substation power supply is mainly stepped down by a 10kV transformer to AC380V to provide the station AC power subsystem, which is rectified by the station AC power supply AC / DC to DC220V / DC110V and the battery is used as a backup power supply to form the station DC power subsystem, which is normally powered by AC , UPS sub-power system with battery backup, the station-use AC power supply AC / DC is rectified to DC48V and the battery is used as a backup power supply to form a station-use DC communication power supply subsystem. The station power system generally does not include photovoltaic and energy storage systems. The battery used as a backup power supply is in a floating charge state for a long time dur...

AI Technical Summary

Problems solved by technology

Conventional 10kV transformers are based on the principle of electromagnetic induction, and do not have the ability to control bidirectional power and power quality

4. The station AC power system does not have the flexible control function; the battery pack in the station DC power system is directly hung on the DC bus. In the case of AC power failure, the battery pack is directly discharged without control and does not have flexible control. Function

6. The battery pack is used as the backup power supply for the DC power supply system for the station, the UPS power supply system for the station, and the communication power supply system for the station. There are unfavorable factors such as heavy maintenance workload and easy failures.

[0010] Question 1: If photovoltaic energy storage is built on a large scale in substations, since conventional transformers do not have the function of controlling the power flow, a large number of substation photovoltaics and energy storage will become uncontrollable power sources for the grid and become unknown factors that affect the safe operation of the grid

[0011] Question 2: If photovoltaic energy storage is connected to the station AC power supply, the instability or failure of the new energy flow will affect the safety and reliability of the station AC power supply; if photovoltaic energy storage is connected to the 10kV bus through a dedicated transformer Although the scheme does not interfere with the station power supply, problem 1 still exists, and it does not optimize the design of the existing station power supply, so it is still an incomplete solution

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