A parallel unified power quality controller and its operation control method

Abstract

The invention relates to a parallel-connected unified power quality control device, which belongs to the technical field of power electronics and flexible AC power transmission and distribution. The device includes a voltage source converter, an energy storage unit, a resonant electronic switch and a main control system. The main control system is composed of a main controller and various sensors; the resonant electronic switch is connected in series Between sensitive loads, the two ports of the resonant electronic switch are respectively PCC 1 Point and PCC 2 point; the AC output port of the voltage source converter is connected to the PCC in parallel 2 point, and its DC side capacitor ports are respectively connected to the corresponding output ports of the energy storage unit; the main controller generates a control gate signal output and is connected to the voltage source converter and the resonant electronic switch. The method is to judge various power quality faults and control the device to quickly switch and operate among four modes; the invention has the advantages of simple structure, low cost, strong overload resistance and high operating efficiency.

Description

technical field [0001] The invention belongs to the technical field of power electronics and flexible AC power transmission and distribution. In particular, it relates to a power quality control device for power distribution and consumption systems, especially to a power electronic circuit device with an energy storage unit and an operation method of the power electronic circuit. Background technique [0002] The factors affecting the status of power quality are very complex, and are generally referred to as power quality disturbances or power quality problems. According to the length of the disturbance duration, it can be divided into two categories: those lasting no more than several seconds are usually classified as discrete disturbances, such as voltage dips, voltage swells, voltage oscillations, and transient overvoltages; Time is a continuous disturbance, such as three-phase voltage unbalance, voltage flicker, voltage harmonics and current harmonics, etc. In the fiel...

AI Technical Summary

Problems solved by technology

Among them, the defect of the series DVR device is that it is only suitable for the voltage drop caused by a short-circuit fault on the system side. For the short-term power supply interruption caused by the tripping of the near-end circuit breaker or the tripping and switching of the upper-level circuit breaker, None of the DVR devices can form an effective compensation loop

The instantaneous value of the line current cannot change suddenly, and the method of simply using the instantaneous value identification may not meet the requirements of rapid identification, so the identification of the slope of the line current is added

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