Control method of power transfer and supply system based on parallel connection of intelligent soft switch and interconnection switch

Abstract

The invention provides a control method of a power transfer and supply system based on parallel connection of an intelligent soft switch and an interconnection switch. The system comprises the intelligent soft switch, the interconnection switch, a first power distribution network and a second power distribution network. After the interconnection switch and the intelligent soft switch are connectedin parallel, two ends are respectively connected with the first and second power distribution networks; the intelligent soft switch comprises a first converter and a second converter; after the intelligent soft switch receives the fault signal, the fault position is judged, when the fault is in the first power distribution network, the first converter is switched from active control to low-voltage ride-through control, and the second converter keeps direct-current voltage control; after receiving the isolated signal, the voltage of the power distribution network is detected, it is judged whether any phase voltage of the first power distribution network is greater than a rated value or not, and the first converter is switched to transition island control when the voltage is greater than the rated value; voltage phase smoothing pre-synchronization control is started; the interconnection switch is closed when the phase frequency of the first power distribution network is the same as thatof the non-fault side; and active output of the intelligent soft switch is set to be zero, reactive compensation control is started at the two ends, and the needed capacity is reduced.

Description

technical field [0001] The invention relates to the technical field of power transmission and distribution, in particular to a control method for a power transfer system based on the parallel connection of an intelligent soft switch and a tie switch. Background technique [0002] Considering the specific characteristics of equipment, protection and control, the distribution network generally operates in an open-loop manner. Therefore, when a permanent fault occurs, the fault isolation power outage area will include non-fault segments. The traditional distribution network operates through circuit breakers. Further isolate the fault outage area, and then restore the power supply to the non-fault outage area by using the live area as the power supply through the contact switch. [0003] As distributed generation, energy storage and controllable loads are expected to be widely connected to the distribution network, their obvious randomness and volatility will bring many problems...

AI Technical Summary

Problems solved by technology

[0004] The embodiment of the present invention provides a control method for the transfer power supply system based on the parallel connection of the intelligent soft switch and the tie switch to solve the impact caused by the potential phase difference when the tie switch is closed in the traditional transfer power supply mode and the problem of using an intelligent soft switch instead of the tie switch. The resulting technical problem of excessive demand for capacity margin avoids the impact caused by the voltage phase difference when the contact switch is closed, and effectively reduces the capacity required for the intelligent soft switch applied to the distribution network to transfer power when a fault occurs

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