The post discusses a 5kva PWM sinewave inverter circuit using compact ferrite core transformer. The idea was requested by Mr. Javeed.
dear sir, would you please modify its output with PWM source and facilitate to make use such an inexpensive and economical design to World wide needy people like us? Hope You will consider my request.Thanking you.Your affectionate reader.
The Circuit Design
In one of my previous post I introduced a ferrite core based 5kva inverter circuit, but since it is a square wave inverter it cannot be used with the various electronic equipment, and therefore its application may be restricted to only with the resistive loads.
However, the same design could be converted into a PWM equivalent sine wave inverter by injecting a PWM feed into the low side mosfets as shown in the following diagram:
The SD pin is mistakenly shown connected with Ct, please be sure to keep it unused or blank.
Suggestion: the IRS2153 stage could be easily replaced with IC 4047 stage, in case the IRS2153 seems difficult to obtain.
As we can see in the above PWM based 5kva Inverter circuit, the design is exactly similar to our earlier original 5kva inverter circuit, except the indicated PWM buffer feed stage with the low side mosfets of the H-bridge driver stage.
For more accurate PWM replication, one can also opt for a Bubba oscilator PWM generator for sourcing the PWM with the above shown 5kva sinewave inverter design.
The construction procedures for the above design is not different to the original design, the only difference being the integration of the BC547/BC557 BJT buffer stages with the low side mosfets of the full bridge IC stage and the PWM feed into it.