【作者】 高然；

【导师】 郭育华；

【作者基本信息】 西南交通大学 ， 电力电子与电力传动， 2013， 硕士

【摘要】 绝缘材料在电机、变压器以及电容器等电气设备中的应用极为广泛,电气设备的绝缘性能往往决定了其运行寿命的长短。绝缘材料的寿命或电气设备的绝缘寿命可通过施加高频、高压、高上升率的脉冲电压进行绝缘老化试验来评估和预测。本论文的主要工作为研制绝缘老化试验电源,重点解决高电压、高上升率、单双极性切换等问题。论文对目前可用于高压脉冲电源设计的几种主要拓扑结构的优点和缺点进行了分析,选择了直流侧隔离、交流侧多个同步工作的高频单项逆变器直接串联输出的技术方案。逆变器直接输出可保证较短的上升时间,而模块串联可实现高电压,各模块同步驱动保证各逆变器的输出电压同步变化,通过调节逆变器的驱动方式,可实现双极性脉冲与单极性脉冲两种方式输出,满足不同情况下的绝缘老化测试需求。针对所选用的技术方案,设计了高压脉冲电源系统。系统包括主控制板与一系列脉冲电源模块。主控制板以TMS320F2812数字信号控制器为核心,通过接收上位机信号,调节输出电压与发出同步驱动信号。脉冲电源模块以CPLD与MOSFET等元件为核心,实现同步脉冲的输出、脉冲极性的切换。实验结果显示输出串联型高压脉冲电源可输出预期的高压与高上升率,能够切换输出脉冲的极性。验证了输出串联模式下,输出脉冲上升率几乎是每个脉冲电源模块输出脉冲上升率的叠加。同时对实验过程中的一些经验进行了记录和总结,并分析了输出串联模式下,导致降低输出的高压脉冲上升率的原因,即各模块逆变电路驱动不同步的主要因素,并提出了改进的方法。通过测试电源的参数指标,电源可达到设计目标。更多还原

【Abstract】 The Application of insulation is very extensive on power devices such as motors, transformers and capacitors. The insulation material determines power devices’ service life, the insulation material performance or power devices’ service life could be estimated and predicted by insulation aging test with high frequency, high voltage and high rise rate pulses. This paper mainly works on developing an insulation aging test pulse generator, to solve problems on high voltage, high rise rate and switching the output pulse polarity.The paper analyzed the benefits and drawbacks of some circuit topologies available in high-voltage pulse generator designs, and selected the cascaded inverters that DC sides are isolated, and AC sides works synchronously. The inverters output pulses directly to ensure high rise rate, and cascading makes high voltage. Power modules are driven synchronously to assure the inverters’ output rise together. Through different driving methods the pulses could be switched between unipolar and bipolar, to meet different testing requirements.According to the scheme, a high-voltage pulse generator was designed. The system includes a control board and a series of power modules. The control board takes TMS320F2812digital signal controller as the core. Through receiving the upper computer’s instructs, the control board adjusts the output voltage, and transmits the synchronal driving signal. The power modules are based on CPLD and MOSFET, to convert AC220V to pulses.The experiment results shows that the high-voltage pulse generator could output the predicted high voltage and high rise rate, and the pulse polarity can be switched. The pulse rise rate of the cascade system is almost the sum of every single module output rise rate. Some experiences in experiments were logged, the reasons that cause the out-sync effect of power modules and reduce the pulse rise rate when outputs are connected in series are also analyzed, and propel solutions were given. Through parameter measurements, the pulse generator meets the requirements.更多还原