电压暂降问题严重影响异步电机的安全稳定运行,已成为备受关注的电能质量问题。为了获得电压暂降相位因素(相位跳变与暂降起始点)对电机运行性能的影响规律,建立了能够模拟电压暂降的电机仿真模型,以5.5 k W、55 k W和135 k W三种电机为...电压暂降问题严重影响异步电机的安全稳定运行,已成为备受关注的电能质量问题。为了获得电压暂降相位因素(相位跳变与暂降起始点)对电机运行性能的影响规律,建立了能够模拟电压暂降的电机仿真模型,以5.5 k W、55 k W和135 k W三种电机为例,系统地研究了电压暂降中的相位跳变与暂降起始点对定子电流峰值、转矩峰值、转速及临界清除时间的影响。结果表明,当暂降过程中计及相位跳变因素时,定子电流与转矩峰值显著增加,转速跌落更加严重且临界清除时间相对缩短;但暂降起始点对上述性能指标影响较小。以5.5 k W电机为例进行了仿真试验对比,验证了分析结果的正确性。展开更多
In order to effectively solve the dead-zone and low-precision of T-shaped transmission line fault location,a new T-shaped transmission line fault location algorithm based on phase-angle jump checking is proposed in th...In order to effectively solve the dead-zone and low-precision of T-shaped transmission line fault location,a new T-shaped transmission line fault location algorithm based on phase-angle jump checking is proposed in this paper.Firstly,the 3-terminal synchronous fundamental positive sequence voltage and current phasors are extracted and substituted into the fault branch distance function to realize the selection of fault branch when the fault occurs;Secondly,use the condition of the fundamental positive sequence voltage phasor at the fault point is equal to calculate all roots(including real root and virtual roots);Finally,the phase-angle jump check function is used for checking calculation,and then the only real root can be determined as the actual fault distance,thereby achieving the purpose of high-precision fault location.MATLAB simulation results show that the proposed new algorithm is feasible and effective with high fault location accuracy and good versatility.展开更多
文摘电压暂降问题严重影响异步电机的安全稳定运行,已成为备受关注的电能质量问题。为了获得电压暂降相位因素(相位跳变与暂降起始点)对电机运行性能的影响规律,建立了能够模拟电压暂降的电机仿真模型,以5.5 k W、55 k W和135 k W三种电机为例,系统地研究了电压暂降中的相位跳变与暂降起始点对定子电流峰值、转矩峰值、转速及临界清除时间的影响。结果表明,当暂降过程中计及相位跳变因素时,定子电流与转矩峰值显著增加,转速跌落更加严重且临界清除时间相对缩短;但暂降起始点对上述性能指标影响较小。以5.5 k W电机为例进行了仿真试验对比,验证了分析结果的正确性。
基金supported by National Nature Science Foundation of China(51507031).
文摘In order to effectively solve the dead-zone and low-precision of T-shaped transmission line fault location,a new T-shaped transmission line fault location algorithm based on phase-angle jump checking is proposed in this paper.Firstly,the 3-terminal synchronous fundamental positive sequence voltage and current phasors are extracted and substituted into the fault branch distance function to realize the selection of fault branch when the fault occurs;Secondly,use the condition of the fundamental positive sequence voltage phasor at the fault point is equal to calculate all roots(including real root and virtual roots);Finally,the phase-angle jump check function is used for checking calculation,and then the only real root can be determined as the actual fault distance,thereby achieving the purpose of high-precision fault location.MATLAB simulation results show that the proposed new algorithm is feasible and effective with high fault location accuracy and good versatility.
