基于伪信号起始时刻法代数求解的变电站局放定位

Partial discharge location in substation based on algebraic solution to pseudo-time of signal

局部放电(局放)的检测是一种有效的对绝缘系统状态评估的非破坏性诊断方法,是及时发现电力设备绝缘缺陷、避免绝缘击穿故障的有效手段。局放类型的探测和局放源的定位直接关系到能否高效地、低成本地开展规划以及落实检修维护工作或者进行风险分析的工作。文中采用局放时辐射出的超高频电磁波信号(UHF信号)进行局放定位:以改进的能量积累函数确定信号的起始时刻:以静态伪距方程代数法求解伪信号起始时刻法建立的关于局放源坐标的非线性方程组,避免了迭代算法对初值的依赖,并在保证计算精度的前提下提高求解速度。最后,经现场测试验证了所提局放定位方法的合理性、有效性。

The detection of partial discharges （PD） is a non-destructive and sensitive diagnostic tool for the condition assessment of insulating system, and an effective method to detect the defects and avoid the breakdown failure of insu- lating system. Type determination and location of the PD are amongst others tremendously important for scheduling and starting maintenance/repair actions cost and time efficiently or to perform a risk analysis. In this paper, the high fre- quency electromagnetic wave signal（ UHF signal）, radiation emitted when PD happened, was used to locate the PD, from which the pseudo-time of signal arrival was determined by the UHF signal after the improved energy accumulation function; algebraic solution method for static pseudo-range equation was used to solve the nonlinear equations of PD coordinates established with pseudo-time of signal arrival method, avoiding the iterative algorithm dependence on the initial value, and ensured the accuracy of calculation and improved the calculation speed. Finally, the rationality and effectiveness of the proposed method were verified by site tests.