Inverter is the main principle of work is to turn the alternating current into direct current, and then the direct current into alternating current, the two processes, alternating current is called rectifier, dc is called inverter, plus some voltage control, filtering, detection circuit, protection circuit, etc..
Rectified current: a large number of the use of diode converter, it will power frequency power supply into a dc power supply.Two groups of transistor converters can also be used to form a reversible converter, which can be regenerated due to its reversible power direction.
Inverter circuit: contrary to the rectifier, the inverter is the dc power conversion to the required frequency of ac power, with a certain time to make 6 switching devices on, off can get 3 phase ac output.
Control circuit: is for asynchronous motor power supply (voltage, frequency adjustable) of main circuit provides the control signal circuit, it has "operation circuit of frequency, voltage, the voltage, current detection circuit of main circuit, the" speed detection circuit of the motor, the operation circuit control signal amplification "drive circuit", and "protection circuit of inverter and motor.
The function of frequency converter is to change the fixed frequency (usually 50Hz) alternating current (three-phase or single-phase) into continuous adjustable frequency (mostly 0-400hz) three-phase alternating current.
Motor speed formula: n=60f/p (p is certain)
According to the above formula, changing the frequency f can continuously change the motor speed n.
The main function of the inverter is mainly used for saving energy, this energy is relative, if used in under power frequency, that is to energy saving, but if has been used in the case, the power frequency for energy saving was almost, another main function is the function of the relative to the soft start, acceleration and deceleration can start at a constant speed, and deceleration time can be set.