死区时间选择的不合理会使逆变器件产生过高的浪涌电压和电流甚至损坏。针对这一问题提出了动态的零电压延迟控制技术,它监测输入供电电压和负载电流,当逆变器功率管达到期望的零电压开关(zero voltage switching,ZVS)条件时,控制功率...死区时间选择的不合理会使逆变器件产生过高的浪涌电压和电流甚至损坏。针对这一问题提出了动态的零电压延迟控制技术,它监测输入供电电压和负载电流,当逆变器功率管达到期望的零电压开关(zero voltage switching,ZVS)条件时,控制功率开关管,使变换器几乎在整个工作条件下都能实现ZVS,而不需考虑输入电压、输出负载和元器件的容差,实现最佳的导通延迟时间。应用该技术的等离子体高频高压电源在纺织材料中的实际应用结果表明:该技术在进一步提高了电源效率的同时,减小了因不合理的死区时间带来的过高的浪涌电压和电流,改善了纺织材料表面改性涂层的性能。展开更多
The primary winding of the transformer will generate large inrush current due to the saturation of iron core when an unloaded transformer is switched-on. The inrush current not only causes mechanical interaction force...The primary winding of the transformer will generate large inrush current due to the saturation of iron core when an unloaded transformer is switched-on. The inrush current not only causes mechanical interaction force due to which the windings are damaged, but also induces the differential protection relays to operate incorrectly. In this paper, the mathematical model of unloaded single phase transformer in switch-on is analyzed; the computation formulas of the inrush current and its interruption angle are presented. The experiment investigation of single phase transformers with different capacities shows that the inrush current measurement result is consistent with theoretical analysis. The inrush current waveform is typically a steeple top waveform with high order harmonics and damping in one direction. In the same condition, large inrush current amplitude will be induced with smaller switching angle, larger residual flux and smaller saturation flux.展开更多
文摘死区时间选择的不合理会使逆变器件产生过高的浪涌电压和电流甚至损坏。针对这一问题提出了动态的零电压延迟控制技术,它监测输入供电电压和负载电流,当逆变器功率管达到期望的零电压开关(zero voltage switching,ZVS)条件时,控制功率开关管,使变换器几乎在整个工作条件下都能实现ZVS,而不需考虑输入电压、输出负载和元器件的容差,实现最佳的导通延迟时间。应用该技术的等离子体高频高压电源在纺织材料中的实际应用结果表明:该技术在进一步提高了电源效率的同时,减小了因不合理的死区时间带来的过高的浪涌电压和电流,改善了纺织材料表面改性涂层的性能。
文摘The primary winding of the transformer will generate large inrush current due to the saturation of iron core when an unloaded transformer is switched-on. The inrush current not only causes mechanical interaction force due to which the windings are damaged, but also induces the differential protection relays to operate incorrectly. In this paper, the mathematical model of unloaded single phase transformer in switch-on is analyzed; the computation formulas of the inrush current and its interruption angle are presented. The experiment investigation of single phase transformers with different capacities shows that the inrush current measurement result is consistent with theoretical analysis. The inrush current waveform is typically a steeple top waveform with high order harmonics and damping in one direction. In the same condition, large inrush current amplitude will be induced with smaller switching angle, larger residual flux and smaller saturation flux.
