Multi-stage Design Method of Broadband Perturbation Signal for Impedance Measurement

Perturbation injection device has become a key tool for obtaining impedance information by administering a perturbation signal to the system under investigation. It is important to reasonably design the injected perturbation signals in order to obtain impedance curves quickly and accurately. This paper proposes a multi-stage design strategy for a broadband perturbation signal (BPS) intended for impedance measurement. Firstly, initial BPS is designed considering various factors affecting the measurement accuracy, including peak, selectable frequencies, and frequency coupling. Then, an error estimation technique is introduced to assess measurement precision, with the ensuing findings applied to the subsequent BPS design stage. The iterative application of these stages allows for the continuous approximation of the real impedance curve. The paper concludes with a series of simulations demonstrating both the practicality and precision of the proposed technique.