Studying of operation balance in single-phase induction motors is an issue of interest due to the need for reducing the power consumption and increasing the motors’ life. The paper focuses on improving the motor perf...Studying of operation balance in single-phase induction motors is an issue of interest due to the need for reducing the power consumption and increasing the motors’ life. The paper focuses on improving the motor performance by balancing the stator phase operation for the most common-used connection diagrams of single-phase capacitor-run induction motors (SPCRIMs) and three-phase induction motors (TPIMs) operating from single-phase supply (SPS). Therefore, a mathematical model is used to balance the motor operation by varying the frequency supply voltage. Characteristics of balancing parameters are investigated, various methods of motor balancing are presented and comparisons were done among these balancing methods.展开更多
直流母线电容作为电机驱动变换器中最薄弱的元件之一,其老化会导致系统故障的概率增大,因此对电容老化进行在线监测至关重要。针对现有监测方法存在经济性差、采样频率高、影响系统正常运行等问题,提出一种基于长周期暂态信号分析的电...直流母线电容作为电机驱动变换器中最薄弱的元件之一,其老化会导致系统故障的概率增大,因此对电容老化进行在线监测至关重要。针对现有监测方法存在经济性差、采样频率高、影响系统正常运行等问题,提出一种基于长周期暂态信号分析的电容在线监测方法,用于估计电机驱动变换器直流母线等值串联电容(equivalent series capacitance,ESC)。首先,根据系统负载切换过程建立共节点感-容等值暂态模型,分析长周期暂态信号特点。其次,推导基于长周期暂态信号的在线监测模型,确定监测程序启动判定条件。然后,提出一种基于多项式重构的电容电流基线校准方法,消除传感器零漂影响,提高监测精度。最后,仿真和实验表明所提出方法的监测精度满足电容监测的要求。展开更多
目前,配电网存在的主要问题为网架薄弱、电网结构不合理、导线截面偏小、供电半径偏大、配电变压器数量和大容量电机负荷增长迅速及负荷功率偏低等,这些问题导致配电线路沿线电压跌落严重、线损高、功率因数低、输送容量小、电压闪变频...目前,配电网存在的主要问题为网架薄弱、电网结构不合理、导线截面偏小、供电半径偏大、配电变压器数量和大容量电机负荷增长迅速及负荷功率偏低等,这些问题导致配电线路沿线电压跌落严重、线损高、功率因数低、输送容量小、电压闪变频繁等。为此本文首先介绍了10 k V串联电容器补偿的工作原理、主要组成以及安装位置和容抗选择,然后分析了异步电动机等效模型,最后通过Matlab仿真,研究了串联补偿电容器不同的安装位置、容抗的大小、并联电阻等情况下,串联补偿电容器对异步电动机启动的影响,为串联电容器补偿装置的设计和工程实践提供了有益的参考。展开更多
文摘Studying of operation balance in single-phase induction motors is an issue of interest due to the need for reducing the power consumption and increasing the motors’ life. The paper focuses on improving the motor performance by balancing the stator phase operation for the most common-used connection diagrams of single-phase capacitor-run induction motors (SPCRIMs) and three-phase induction motors (TPIMs) operating from single-phase supply (SPS). Therefore, a mathematical model is used to balance the motor operation by varying the frequency supply voltage. Characteristics of balancing parameters are investigated, various methods of motor balancing are presented and comparisons were done among these balancing methods.
文摘直流母线电容作为电机驱动变换器中最薄弱的元件之一,其老化会导致系统故障的概率增大,因此对电容老化进行在线监测至关重要。针对现有监测方法存在经济性差、采样频率高、影响系统正常运行等问题,提出一种基于长周期暂态信号分析的电容在线监测方法,用于估计电机驱动变换器直流母线等值串联电容(equivalent series capacitance,ESC)。首先,根据系统负载切换过程建立共节点感-容等值暂态模型,分析长周期暂态信号特点。其次,推导基于长周期暂态信号的在线监测模型,确定监测程序启动判定条件。然后,提出一种基于多项式重构的电容电流基线校准方法,消除传感器零漂影响,提高监测精度。最后,仿真和实验表明所提出方法的监测精度满足电容监测的要求。
文摘目前,配电网存在的主要问题为网架薄弱、电网结构不合理、导线截面偏小、供电半径偏大、配电变压器数量和大容量电机负荷增长迅速及负荷功率偏低等,这些问题导致配电线路沿线电压跌落严重、线损高、功率因数低、输送容量小、电压闪变频繁等。为此本文首先介绍了10 k V串联电容器补偿的工作原理、主要组成以及安装位置和容抗选择,然后分析了异步电动机等效模型,最后通过Matlab仿真,研究了串联补偿电容器不同的安装位置、容抗的大小、并联电阻等情况下,串联补偿电容器对异步电动机启动的影响,为串联电容器补偿装置的设计和工程实践提供了有益的参考。
