UNIT6-powerelectronictechnologyexperimentguid讲义.doc

UNIT 6 Power Electronics Laboratory User Manual① Key words and terms 1. converter n. 变流器、变换器 2. buck converter 降压变流器 3. arcing n. 电弧、放电 4. first aid adj. 急救的 5. kit n. 装备,工具箱transformer n. 变压器 7. oscilloscope n. 示波器 8. CPR（cardiopulmonary resuscitation）心复苏术[.kɑ:di?up?lm?n?ri] [ri.s?sitei??n; ri.s?s?tei??n] 9. boost converter 升压变流器 10. duty ratio 占空比 11. CCM Continuous Current Mode 12. ripple n. （波形）脉动 13. step-up transformer. 升压变压器 Cardio- （word root） 心脏、心的 Cardiopulmonary a. 心肺的 Note and Translation SAFETY PRECAUTIONS 1 Why is safety important ? Attention and adherence to safety considerations is even more important in a power electronics laboratory than it’s required in any other undergraduate electrical engineering laboratories. Power electronic circuits can involve voltages of several hundred volts and currents of several tens of amperes. By comparison the voltages in all other teaching laboratories rarely exceed 20V and the currents hardly ever exceed a few hundred milliamps. adherence n. 吸附、固着、坚持、遵守 In order to minimize the potential hazards, we will use dc power supplies that never exceed voltages above 40-50V and will have maximum current ratings of 20A or less. Most of the time we will use dc supplies of 20V or less and 1 A or less output current capability. However in spite of this precaution, power electronics circuits on which the student will work may involve substantially larger voltages (up to hundreds of volts) due to the presence of large inductances in the circuits and the rapid switching on and off of amperes of current in the inductances. For example a boost converter can have an output voltage that can theoretically go to infinite values if it is operating without load. inductance n. 电感 theoretically ad. 理论上地 Moreover the currents in portions of some converter circuits may be many times larger than the currents supplied by the dc supplies powering the converter circuits. A simple buck converter is an example of a p