The voltage type is the DC converter of the voltage source to the AC frequency converter. The current type is a converter which converts the DC current source into AC. The main circuit of inverter and rectifier, inverter circuit and the flat wave of three parts, the power supply conversion to DC power rectifier, voltage ripple absorption in converter and inverter "flat wave circuit search.
Frequency converter
1, it is the role of three-phase rectifier (or single-phase) AC power rectifier into DC power supply. In the SPWM converter, most of the full wave rectifier circuit. Most of the medium and small capacity of the inverter, the rectifier device is not controlled rectifier diode or diode module.
2, it is the role of inverter and rectifier, DC inverter is the voltage and frequency of alternating current to achieve AC motor frequency control. The inverter circuit is made up of switching devices, and most of them are bridge circuit. In the SPWM converter, the switching device receives the control signal of the SPWM modulation in the control circuit, and converts the direct current to the three-phase alternating current.
3, the control circuit of this part of the circuit by the circuit, detection circuit, drive circuit, protection circuit, etc., are generally used in large scale integrated circuit.