A novel fundamental frequency detection method based on a new duffing oscillator

A new method to measure fundamental frequency of power system based on a new Duffing oscillator was proposed in this paper.The measurement error was analyzed in theory,and the method to improve the measurement precision was proposed.Comparing with the traditional Duffing oscillator,the proposed new Duffing oscillator has two significant features.One is that the critical chaotic amplitude does not significantly vary with changes of the driving frequency and sampling frequency,and the other is that it can effectively surpass the limitation of the traditional Duffing oscillator which can only detect low frequency signal.The new Duffing oscillator has a good performance applied to detect fundamental frequency of power grid.Simulation results show that the new Duffing oscillator not only has good noise immunity characteristics,but also effectively improves the detection precision of the fundamental frequency of power system.