CAJ | 학술논문

为及时发现电力变压器绕组变形等潜伏性故障,需要实时监测变压器绕组的状态.建立了变压器绕组的数学模型,利用变压器原、次边的电压、电流信号对变压器的短路阻抗进行在线辨识.其方法是:实时采集模型变压器原、次边的电压、电流信号后,针对电压、电流传感器采集信号的特点,应用小波变换除去噪声,再利用基于离散傅里叶变换的高精度相位识别法辨识各正弦量间的相位差,得到各负载情况下变压器绕组等效电路的短路阻抗.利用模型三相变压器搭建的变压器绕组状态监测平台进行实验,结果表明,变压器绕组未发生状态改变时,不同负栽情况下短路阻抗的辨识差别不超过0.64%:若变压器绕组发生变形及匝间短路等故障,短路阻抗的变化量达到5.6%以上,证明所提出的监测算法是有效的.
위급시발현전력변압기요조변형등잠복성고장,수요실시감측변압기요조적상태.건립료변압기요조적수학모형,이용변압기원、차변적전압、전류신호대변압기적단로조항진행재선변식.기방법시:실시채집모형변압기원、차변적전압、전류신호후,침대전압、전류전감기채집신호적특점,응용소파변환제거조성,재이용기우리산부리협변환적고정도상위식별법변식각정현량간적상위차,득도각부재정황하변압기요조등효전로적단로조항.이용모형삼상변압기탑건적변압기요조상태감측평태진행실험,결과표명,변압기요조미발생상태개변시,불동부재정황하단로조항적변식차별불초과0.64%:약변압기요조발생변형급잡간단로등고장,단로조항적변화량체도5.6%이상,증명소제출적감측산법시유효적.
The status of transformer windings should be monitored in real.time to detect their potential faults.The mathematical model of transformer windings is established and its short.circuit impedance is on.1ine computed with the voltage and current signals at both sides.The signals mentioned above are sampled in real.time and denoised by the wavelet transformation according to the characteristics of voltage and current sensors.By precisely scaling the phase differences based on discreet Fourier transform.the short-circuit impedances of the transformer windings are identified under various load conditions.Experiments are carried out on the windings monitoring platform built with model transfoFiller and the results show that,the difference between short.circuit impedance measurements under various 10ad conditions does not surpass 0.64%when there is no winding status change.whereas if there is interturn short-circuit or winding deformation,change of short-circuit impedance reaches up to 5.6%,proving the effectiveness of offered on-line monitoring algorithm.