Inverters are an electric devices which control the work of electric motors. Inverters controls the speed of electric motors by changing frequency and voltage. Precision frequency change protects engines from damage. In recent years inverters are a very popular device, because they are very functional. Currently, the inverters used in almost all field of automation and industry.
There are two basic types of inverters: scalar and vector. Scalar Inverters with algorithm U/f used for easy application, less accurately control the rotation speed. Among the devices with such inverters are: fans, pump, blowers, compressor. Vector inverters are used there where it needs to be very accurate control of motor speed. We use them where it operates more electric motors. Another division relates to a method of power. Inverters can be divided even on 1-phase and 3-phase.
Modern inverters are compact and easy to use. Inverters often have a built-in display, memory and program control. An important element are brake resistors, which reduce the possibility of damage to the inverter. Recent inverters also have the function of the PLC. They also have the ability to communicate with RS232 or RS485 ports.