Compensation system for medium or high voltage applications

摘要

A compensating system for a power system includes a compensator including semiconductor switch means, which compensator has phase legs which on a first side of the compensator defines AC inputs for connection to a respective phase of the power system. The phase legs are connected in wye connection at a second side of the compensator, which wye connection has a neutral point. A filter arrangement at a first side thereof is connected to the neutral point of the wye connection and at a second side is connected to the AC inputs to thereby form a circuit with the compensator. The filter arrangement is arranged such that the circuit acts essentially as an open circuit for positive sequence currents or voltages and negative sequence currents or voltages, and as a closed circuit for zero-sequence currents.

主权项

1. A compensating system for a power system, wherein the compensating system comprises:
a compensator comprising semiconductor switch means, which compensator has phase legs which on a first side of the compensator defines AC inputs for connection to a respective phase of the power system, wherein the phase legs are connected in wye connection at a second side of the compensator, which wye connection has a neutral point, and a filter arrangement which at a first side thereof is connected to the neutral point of the wye connection and at a second side is connected to the AC inputs to thereby form a circuit with the compensator, wherein the filter arrangement is arranged such that the circuit acts essentially as an open circuit for positive sequence currents and voltages and negative sequence currents or voltages, and as a closed circuit for zero-sequence currents, wherein the filter arrangement is further arranged to block a zero-sequence current having a fundamental frequency and to allow a harmonic of the zero-sequence current to pass therethrough, whereby the harmonic of the zero-sequence current is able to flow through the closed circuit.