A Control Method for Chirp Signal Injecting of DCDC Voltage Source Converter

Impedance measurement is an important issue in the field of stability estimation in energy internet. A commonly used method is injecting a small perturbing signal to the accessed equipment and measure its response, thereby obtaining its impedance characteristic. The chirp signal is a non-random signal with short perturbation time and rich spectral components, which has been widely used as the perturbing signal for impedance measurement. Since the conventional control method of converters is not suitable for superimposing high frequency perturbing signal components directly on the power components, a control method for chirp signal injecting of the DC-DC voltage source converter is proposed in this paper. With a 10kW NIBB converter prototype, the experiment and simulation results show that the chirp signal can be injected well using the proposed method, and the problems of resonance and instability under certain special load conditions can be effectively avoided.