With the advent of sophisticated electronic power control systems, the power efficiencies of electric and electronic devices and machines have been improved significantly. This improvement in efficiency is quite obvious in rotating electric machines such as motors. In other words, electric or hybrid electric vehicles would not gain so great a popularity, if motors in such vehicles were driven or controlled without using power electronic devices. One of the most typical and most important power electronic device systems is a converter system, which is composed of an inverter circuit that converts dc to ac and a converter circuit that converts ac to dc.

中文翻译：

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来自日本的新闻

随着复杂的电子功率控制系统的出现，电气和电子设备及机器的功率效率已得到显着提高。在诸如电动机的旋转电机中，效率的这种提高是非常明显的。换句话说，如果在不使用电力电子设备的情况下驱动或控制此类车辆中的电动机，则电动或混合动力电动车辆将不会获得如此大的普及。转换器系统是最典型且最重要的电力电子设备系统之一，该转换器系统由将dc转换为ac的逆变器电路和将ac转换为dc的转换器电路组成。