自适应扰动与集成高精度信号提取方法在低压IBR导纳测量装置中的应用

Wideband admittance measurement devices are essential tools for validating and correcting the admittance model of inverter-based resources (IBRs). During the measurement process using the low-voltage wideband admittance measurement device, the perturbation injection unit (PIU) exhibits multi-frequency voltage ripples on its DC-side. Such pronounced ripple voltage fluctuations not only increase protection tripping risks but also constrain the allowable perturbation amplitude, leading to degrades the accuracy of admittance measurement results. To address this issue, this paper first establishes the mathematical model of DC-side ripple voltage during perturbation injection. The effects of the perturbation voltage on the DC-side ripple voltage are analyzed, revealing the boundary of the perturbation amplitude considering the allowable DC-side voltage fluctuation limits. Then, considering the perturbation amplitude boundary, spectral leakage (SL), and noise interference, an adaptive perturbation voltage injection method with integrated high-precision signal extraction is proposed. The proposed method adaptively adjusts the perturbation amplitude based on the PIU’s amplitude boundary and the SNR requirements, ensuring both measurement accuracy and the stability of the DC-side voltage within safe operating limits. Finally, a 380V/10kVA low-voltage wideband admittance measurement device is developed. The effectiveness of the proposed method is verified by experiments.