摘要
采用基于离散傅立叶变换 (DFT)的谐波分析法测量介损时 ,因电网频率波动使测量精度不能满足标准要求。因此提出了基于准同步DFT的介损测量法。该方法能有效减小未完全整周期采样所造成的测量误差。数值仿真结果表明 ,该方法的测量精度明显高于谐波分析法 ,当频率波动时对不同电流、电压信号的初相角 ,其测量精度均能满足绝对误差 <0 1% ,且计算量小 。
Due to the system frequency fluctuation, the signal frequency would be non-integer times of the sampling frequency and the leakage effect appears, thus, the accuracy of the dielectric loss measurement based on the DFT method can not meet the standard requirement. However, the result of the phase angle difference measurement based on the Quasi-synchronous DFT method is much more accurate than that based on the DFT method, when the sampling is non-synchronous. Thereby, in this paper, a method based on the Quasi-synchronous DFT method is proposed to measure the dielectric loss. The results of the simulation, under the condition that the frequency is fluctuating and current and voltage signals have different initial phase angles, have demonstrated that the measurement accuracy of the proposed method is enhanced significantly.
出处
《高电压技术》
EI
CAS
CSCD
北大核心
2004年第10期44-45,共2页
High Voltage Engineering
