High-Precision Measurement Technology of Reference Voltage for Feeder Verification Based on PIA-Bi-Directional FIR

To address the issue that voltage signals in the measurement circuits of distribution network feeders are susceptible to non-uniform sampling, wideband interference, and phase distortion during operation, which fails to meet the accuracy requirements of on-line verification, a high-precision measurement technology for feeder calibration reference voltage based on PIA-bidirectional FIR is proposed. Taking the bus voltage of the distribution network as the on-line reference benchmark, the proposed technology adopts a three-stage collaborative processing framework consisting of cubic spline Hermite interpolation reconstruction via PIA, bidirectional FIR filtering, and improved VMD-TLS-ESPRIT parameter identification to extract high-fidelity amplitude, phase, and frequency parameters of voltage. It can serve as a reference source for live on-line verification of feeder measurement circuits. Simulation results demonstrated that the amplitude error of waveforms reconstructed by the proposed technology was less than 0.05%, the phase error better than 0.36 arcseconds, and the frequency tracking error superior to 0.001 Hz. Compared with conventional methods, the presented technology achieves higher frequency tracking accuracy and better phase stability, which can effectively satisfy the demands of on-line verification for measurement circuits of distribution feeders.