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

Abstract

The invention provides a control method for a power supply system based on the parallel connection of an intelligent soft switch and a tie switch. The system includes an intelligent soft switch, a tie switch, a first distribution network and a second distribution network; The terminals are respectively connected to the first and second distribution networks. The intelligent soft switch includes the first converter and the second converter; the intelligent soft switch judges the fault location after receiving the fault signal. When the fault is in the first distribution network, the first The converter is switched from active power control to low voltage ride-through control, and the second converter maintains DC voltage control; after receiving the isolated signal, it detects the voltage of the distribution network to determine whether the voltage of any phase of the first distribution network is greater than the rated value , when it is greater than the rated value, switch the first converter to transition island control; start the voltage phase smoothing pre-synchronization control; close the tie switch when the phase frequency of the first distribution network is the same as that of the non-fault side; set the active power of the intelligent soft switch to zero output, reactive power compensation control is activated at both ends, reducing the required capacity.

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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