The working principle of the inverter

1 . Full-controlled inverter works: Figure 3 shows , for the full-bridge inverter main circuit commonly used single-phase output figure, the AC components using
the IGBT Q11, Q12, Q13, Q14. Controlled by the PWM pulse width modulation IGBT tube turned on or off .
   When the  4000 watt power inverter  circuit connected to a DC power source , first Q11, Q14 is turned on , Q1, Q13 is turned off, the current from the positive output of theDC
power supply , via Q11, L or sense transformer primary winding 1-2, back to Q14
to the negative power supply . When Q11, Q14 after the deadline , Q12, Q13 is
turned on , current flows from the positive power supply through Q13, electrical
transformer primary winding 2-1 am Q12 back negative power . In this case, the
transformer primary winding , has formed an alternating positive and negative
square wave , the use of high frequency PWM control , two pairs of IGBT tube
alternately repeated , generating an AC voltage on the transformer . Since LC AC
filter effect, so that the output AC voltage sine wave form .
   When Q11, Q14 off when , in order to release the stored energy in the IGBT
diode in parallel at D11, D12, so that energy back to the DC power supply to go.Th2 is triggered according conduction, because reverse biased anode Th2 , Th1
off, return the blocking state . Thus , Th1 and Th2 commutation , and then charge the capacitor C and reverse polarity . So turn triggered thyristors ,
alternating current flows transformer primary , the secondary of the transformer
to get the AC .
   In the circuit, the inductance L can be limited for the discharge current of
the capacitor C , to extend the discharge time to ensure that the circuit is
greater than the turn-off time of the  220 volt power inverters  turn-off time without a large
capacity capacitor . D1 and D2 are two feedback diode , inductor L can be the
energy release , it will be returned to the remaining energy supply , completethe feedback energy.