SEW DFI11B-512510
变频器(Variable-frequency Drive,缩写: VFD )，也称为变频区动器或驱动控制器，在日本的商品名称用Inverter，和逆变器的英文相同变频器的英文名称Variable-frequency Drive，是现代科技中少数源自中文者之一
变频器是可调速驱动系统的一种，是应用变频驱动技术改变交流电动机工作电压的频率和幅度，来平滑控制交流电动机速度及转1]2]:p210-21513]4:p4，最常见的是输入及输出都是交流电的交流/交流转换器。在变频器出现之前，要调整电动机转速的应用需透过直流电动机才能完成不然就是要透过利用内建据合机的VS电动机，在运转中用合机使电动机的实际转速下降，变频器简化上述的工作，缩小设备体积，大幅度降低维修率，不过变频器的电源线及电动机线上面有高频切换的讯号，会造成电磁干扰，而变频器输入侧的功率因数一般不佳，会产生电源端的谐波

变频器的应用范围很广，从小型家电到大型的矿场研磨机及压缩机，全球约1/3的能量是消耗在驱动定速离心泵、风扇及压缩机的电动机上，而变频弱的市场渗透率仍不算高，利用变频器来控制电动机的转速，带来能源效率的显著提升，是使用变频器的主要原因之一。变频器技术和电力电子有密切关系，包括半导体切换元件、变频器拓扑、控制及模拟技术、以及控制硬件及固件的进步等。

Variable frequency drive (VFD), also known as variable frequency zone actuator or drive controller, is a Japanese product name called Inverter, which is the same as the English name of inverter. The English name of variable frequency drive is one of the few modern technologies that originated from Chinese
A frequency converter is a type of adjustable speed drive system that uses variable frequency drive technology to change the frequency and amplitude of the working voltage of an AC motor, in order to smoothly control the speed and rotation of the AC motor. The most common type is an AC/AC converter with b and output of AC power. Before the emergence of frequency converters, the application of adjusting the motor speed needed to be completed through a DC motor. Otherwise, it would need to use a built-in VS motor to reduce the actual speed of the motor during operation. The frequency converter simplifies the above work, reduces the equipment volume, and significantly reduces maintenance rates. However, there are high-frequency switching signals on the power and motor lines of the frequency converter, which can cause electromagnetic interference, However, the power factor on the b side of the frequency converter is generally poor, resulting in harmonics at the power supply end
The application range of frequency converters is very wide. From small household appliances to large mining grinders and compressors, about one-third of the b energy is consumed by electric motors that drive constant speed centrifugal pumps, fans, and compressors. However, the market penetration rate of weak frequency converters is still not high. The use of frequency converters to control the speed of electric motors brings significant improvement in energy efficiency, which is one of the main reasons for using frequency converters. Inverter technology is closely related to power electronics, including semiconductor switching components, inverter topology, control and simulation technology, as well as the advancement of control hardware and firmware.