一种在线监测绝缘介质损耗的方法

A Method for Online Measurement of Dielectric Loss of HV Capacitive Equipment Insulation

电气设备绝缘介质损耗的在线监测技术 ,一直是国内外学者研究的重点 ,尤其是监测的新方法 ,更是受人关注 ,目前 ,还未看到一种用于在线监测令人满意的方法。文中以电压、电流过零点相位差原理为基础 ,提出了一种用电压、电流波形积分的测量方法来在线监测电容型电气设备的介质损耗 ,文中详细分析和推导了数学计算公式 ,并用数字模拟仿真给出了计算结果 ,同时 ,阐明了系统频率、谐波含量和零点漂移等因素对测量带来的影响 ,给出了相应的误差曲线 ,提出了减小误差、提高测量稳定性和准确度的措施。作者认为积分测量法可以将小信号测量转换为大信号测量 ,在强电磁干扰环境中具有较高抗干扰能力 ,在用于在线监测时 ,能较为准确地测量出电容型电气设备的介质损耗。

It is still a major problem for research on online monitor dielectric dissipation factor of high voltage equipment insulation. In the field, new methods are paid attention by researchers especially. At present, there are no methods achieving the satisfactory measurement results. Based on the voltage and current at their respective zero crossed points, this paper proposes the integral measurement method which can be used to measure the dielectric dissipation factor of high voltage capacitive apparatus. The formula for dielectric dissipation factor angle computation is deduced by theoretical analysis and the computation results are achieved by digital simulation. Meanwhile, this paper explains the effect to measurements by system frequency, content of harmonic and zero-drift and draws the relevant error curves. It also proposes the measures to reduce the integral measurement method presented in this paper,which can convert measurement of small signal into that of big signal and accurately measure dielectric loss of capacitive apparatus. It also possesses great anti jamming ability under strong electromagnetic interference environment. The online measurement system can detect the dielectric dissipation factor of high voltage equipment by the integral measurement method.