Voltage and current unbalance problems of power networks due to AC electrified railway systems are studied and their influences such as the voltage unbalance factor and the current negative sequence contribution factor injected to the network are calculated. Several methods can be used for reducing the power quality unbalance problems which have been proposed and the best of them is chosen by c...

In this paper negative sequence components are used for islanding detection in distributed generation (DG) based system. In this approach, the negative sequence component of the voltage and current signals are analyzed through wavelet transform. The detailed coefficient d1 clearly identifies the event and thus detects the islanding condition. The change in energy and standard deviations of wave...

Abstract At present, the current positive and negative sequence extraction methods are all based on high-performance analog-to-digital converters need microprocessors. Or measurement circuit is constructed using an analog operational amplifier, phase shifting method used to achieve purpose. The above be implemented by chips with high computing power. They even build additional circuit, which ma...