摘要
保护性触发是特高压直流(UHVDC)换流阀的一项重要保护功能,对单阀绝缘试验中的操作冲击耐受试验有重要影响,进行该试验对电压测量准确性要求较高。进行某型号特高压换流阀保护性触发试验时,在测量设备采集到的试验电压峰值未达到设计的阀保护性触发动作门槛时发生了整阀触发导通,初步分析认为是阀塔动作正确,但测量设备与换流阀之间存在杂散电容导致试验电压的测量不准确。采用ANSYS仿真软件计算出试验回路中各主设备间的杂散电容矩阵,根据杂散电容和试验回路参数建立了PSCAD仿真模型,仿真得到了分压器测量值和阀实际承受电压值,复现了试验问题;通过理论计算分析优化试验方案,并进行了试验验证。结果表明:分压器、冲击发生器和换流阀之间的杂散电容对电压测量结果影响明显;根据ANSYS计算出杂散电容,根据杂散电容和试验回路参数建立PSCAD仿真模型,仿真结果与试验现象一致;通过试验方法的优化,电压测量偏差系数将由97.5%提高至99.2%,优化效果明显。
Protective firing test is an important protection function of UHVDC converter valves.It has important influence on the switching impulse withstand test of single-valve insulation tests.Performing this test requires high voltage measurement accuracy.During the protective triggering test of a certain type of UHV converter valve,the whole valve triggering conduction occurs when the peak value of the test voltage collected by the measuring equipment does not reach the designed threshold for the protective triggering action of the valve.The preliminary analysis believes that the valve tower operates correctly,but stray capacitance between the measuring equipment and the converter valve leads to inaccurate measurement of test voltage.This paper uses ANSYS simulation software to calculate the stray capacitance matrix between each main equipment in the test loop.And then,according to the stray capacitance and the parameters of the test circuit,the paper establishes PSCAD simulation model,and obtains the measured value of the voltage divider and the actual voltage bearing value of the valve by simulation,with the test problem reproduced.Finally,the paper makes further theoretical calculation to analyze and optimize the test plan,and conducts experimental verification on the optimized test scheme.The results show that the stray capacitance between the voltage divider,impulse generator and the converter valve has obvious influence on the voltage measurement results,that the simulation results are consistent with the experimental results whether calculating the stray capacitance according to ANSYS,or establishing the PSCAD simulation model according to the stray capacitance and the test loop parameters,and that through the optimization of the test method,the voltage measurement deviation coefficient will be increased from 97.5%to 99.2%,with obvious optimization effect.
作者
张子敬
张翔
孙健
赵赢峰
方太勋
ZHANG Zijing;ZHANG Xiang;SUN Jian;ZHAO Yingfeng;FANG Taixun(NR Electric Co.,Ltd.,Nanjing Jiangsu 211102,China)
出处
《湖北电力》
2020年第2期20-26,共7页
Hubei Electric Power
基金
国网电力科学研究院有限公司科技项目(项目编号:JS1900543)。
作者简介
张子敬(1987),男,山东菏泽人,硕士,工程师。
