A novel self-fault recovery system and control method of a multifunctional current limiter

Abstract

The invention discloses a novel self fault recovery system of a multifunctional current limiter and a control method of the novel self fault recovery system. The recovery system is mainly composed of a standby bridge arm 1, a standby bridge arm 2, self fault set selection switches K[w], self fault set selection switches K[n] and by-pass switches. The standby bridge arm 1 is connected with three bridge arms of a PWM rectifier through the self fault set selection switch K[w1], the self fault set selection switch K[w2] and the self fault set selection switch K[w3] of the self fault set selection switches K[w] and the standby arm 2 is connected with the three bridge arms of the PWM rectifier through the self fault set selection switch K[w4], the self fault set selection switch K[w5] and the self fault set selection switch K[w6] of the self fault set selection switches K[w] so that rapid recovery of faults of less than two bridge arms of the PWM rectifier can be achieved. The standby bridge arm 2 is connected with four bridge arms of a PWM inverter through the self fault set selection switch K[n1], the self fault set selection switch K[n2], the self fault set selection switch K[n3] and the self fault set selection switch K[n4] of the self fault set selection switches K[n] and the standby bridge arm 1 is connected with the four bridge arms of the PWM inverter through the self fault set selection switch K[n5], the self fault set selection switch K[n6], the self fault set selection switch K[n7] and the self fault set selection switch K[n8] of the self fault set selection switches K[n] so that rapid recovery of faults of less than two bridge arms of the PWM inverter can be achieved. The by-pass switch K[1], the by-pass switch K[2] and the by-pass switch K[3] are connected to one side of a series transformer T[1], one side of a series transformer T[2] and one side of a series transformer T[3] respectively. When the by-pass switches are switched on, the conditions that the system is usable without standby bridge arms and continuous power supply of the system is achieved when thyristor disconnection of a thyristor branch circuit occurs are guaranteed.

Description

technical field [0001] The invention belongs to the technical field of power electronics application, and relates to a novel self-fault recovery system of a multifunctional current limiter and a control method thereof. Background technique [0002] The basic requirements for power system operation are safety, reliability, high power quality, and good economy. However, with the rapid development of distributed power sources such as the photovoltaic industry and the gradual increase in power electronic load devices in recent years, the power quality problem in the power system has become more prominent, and at the same time it is limited by the periodic power of photovoltaic power generation, small hydropower and other power sources. Influenced by the characteristics, the voltage fluctuation of the system also gradually increases. On the other hand, with the leap-forward development of the large power grid, the system capacity continues to increase, resulting in an increasing...

AI Technical Summary

Problems solved by technology

However, the multifunctional current limiter is connected in series to the system, and the current flowing through the current limiter is the same as the load current. Once the current limiter itself fails, it will force the load to be powered off, and the power supply continuity will be seriously reduced. Therefore, it is necessary Propose a self-fault recovery system for multi-function current limiter

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