Filter bank based technique for flicker signals detection and estimation of power signals

Voltage fluctuations are one of the power quality problems, which cause light flickers. Generally, voltage fluctuations are described as an amplitude modulation (AM). To determine the flicker severity, the flickermeter concept was developed in an IEC 61000-4-15 standard. Flickermeter of IEC 61000-4-15 as an international standard for flicker measurement recommends square demodulation method to detect flicker signals. This paper suggests a new effective method using filter bank to detect and estimate flicker signals, which is effective in comparison with square demodulation method. For the accurate detection of flicker signals, the filter bank is designed with a full consideration of the spectrum characteristics of AM signals. The frequency and magnitude of the detected signals by the filter bank are estimated using recursive method. Computer simulations were performed on synthesized signals to prove validity of the proposed method.