Evaluating Rapid Voltage Changes and its Propagation Effect using Multipoint Measurement Technique

A multipoint measurement technique for detecting rapid voltage changes causing electromagnetic interference, and its propagation effect in a power distribution network, is presented. The main advantage of the proposed techniques lies in its capability to detect rapid voltage change disturbance and its correlation with other electromagnetic interference events simultaneously. This is achieved by combining a multipoint measurement technique and a coincidence ratio evaluation method. A multipoint measurement technique was applied by using four distributed power quality analyzers which record conducted electromagnetic interference events. The recorded data is evaluated using the coincidence ratio and the time gap analysis method. The results show that a rapid voltage change in a 440 V power distribution subsystem has a probability in between 70 % and 93.8 % of triggering a sag in an uninterrupted power supply, and thus electromagnetic interference towards other subsystems.