【摘要】：為降低電子式電流互感器(ECT)的暫態(tài)誤差、提高穩(wěn)態(tài)電流的測量準確度,提出了一種應用于羅氏線圈ECT信號采集系統(tǒng)的壓頻變換器模數(shù)混合積分器(VFC-ADI)方法。對羅氏線圈輸出信號進行壓頻數(shù)值轉(zhuǎn)換,由脈沖計數(shù)器完成數(shù)值計數(shù),微處理器對計數(shù)值處理后得出被測電流的積分波形。選取VFC芯片AD7742進行仿真分析,仿真結(jié)果顯示VFC-ADI方法能準確地反映一次側(cè)暫態(tài)電流波形。對羅氏線圈ECT暫態(tài)故障電流及穩(wěn)態(tài)電流進行試驗測試,結(jié)果表明VFC-ADI方法能準確反映暫態(tài)故障電流特征;對于穩(wěn)態(tài)電流測試,比差的變化范圍為-0.15%~0.15%,角差的變化范圍為-1′~1.5′,其輸出值完全滿足0.2 s級基本準確度測試要求。VFC-ADI方法在模數(shù)轉(zhuǎn)換過程中實現(xiàn)了積分功能,數(shù)據(jù)處理結(jié)果表明其更接近于理想積分器。
[Abstract]:In order to reduce the transient error of electronic current transformer (ECT) and improve the accuracy of steady-state current measurement, a voltage-frequency converter analog-to-digital hybrid Integrator (VFC-ADI) method for Roche coil ECT signal acquisition system is proposed. The output signal of Roche coil is converted into voltage and frequency, and the numerical counting is completed by pulse counter. The integral waveform of the measured current is obtained after the microprocessor processes the counting value. The VFC chip AD7742 is selected for simulation analysis. The simulation results show that the VFC-ADI method can accurately reflect the transient current waveform on the primary side. The transient fault current and steady state current of Roche coil ECT are tested and tested. The results show that the VFC-ADI method can accurately reflect the characteristics of transient fault current. For the steady-state current test, the variation range of the specific difference is-0.15% 鈮，

本文編號：2496802