Hi,

I need to switch the 220v dc to load while pressing pushbuttons. I am having +220v dc in capacitor bank which will be made available to load as +220v while pressing one button and -220v while pressing second button.

So, I am planning to desing a H bridge using IGBT's and driver ic's as IR2110. By coming across several forums and tutorial i came to know that the driver ic is the optimum choice in order to drive the IGBT fully on. The IR2110 has HIN and LIN pins for which pwm signal has to be given which controls high side and low side switching. The high side should have bootstrap capacitor circuit in order to drive the high side igbt.

I want to know how to generate the pwm signals for HIN and LIN of IR2110. I dont want to do the switching operation at a particulat frequency. If I press one button IGBTs Q1 and Q4 should ON in order to provide +220v to the load. While pressing the second button IGBTs Q2 and Q3 should ON in order to provide -220v to the load.

I have attached the kind of circuit which I am planning to use for this (got the circuit from net). I need clarifications in generating pwm signal for switching the igbts and also about bootstrap circuit.

 

You need to cross connect the Hi and Li on the U1and U2 chips, so that when U1 is high U2 is low.
Or feed the pwm in U1, and the direction into U2.

For pwm you can use a microcontroller or pwm chip like TL494, or 555 timer.

 

Are you saying to short the HIN of U1 with LIN of U2 and LIN of U1 with HIN of U2. Then i have to give pwm signal is it correct?

The button which i mentioned is in a control device. It has two output terminals (for two buttons). The output terminal is like relay i.e (each output terminal has two pins when the button is pressed the two pins will get shorted so whatever signal i am giving in the first pin will be available to second pin). There is also timing option available in the range of 0.01 to 2 secs for that shorting of pins (the output pins shorting time while pressing button). I have to give the generated pwm through this output terminal in order perform the switching.

At what frequency PWM signal has to be generated. I guess that pwm signal has to be of lower frequency in the range of tens of hertz. I am not sure at which frequency the desired result can be achieved.

 

Correct with U2 and U1. As for the frequency of pwm is upto the limit of the motor and mosfets.

 

By coming across several forums and tutorial i came to know that the driver ic is the optimum choice in order to drive

That driver is not in my opinion the "optimal" It's just the one that has been used by people. It's an old part, and doesn't have a very high amperage output and it is amperage that turns on a mosfet fast. There are many newer, higher amperage drivers now available. The FAN7390 and the other FANxxxx series is a much higher output diver and has all of the same inputs of the IR2110.

https://www.fairchildsemi.com/produ...gate-drivers/half-bridge-drivers/FAN7390.html

 

As for the frequency of pwm is upto the limit of the motor and mosfets.

I couldn't understand this one. What is limit you are referring in this statement.

 

I finally came up with this circuits and getting desired result when using 12v dc motor as load. But, while trying 220v dc and lamp as load the low side parts gets damaged. The igbts are getting shorted. Is there any flaws in the circuit.

I got output for lamp and using 110v dc as load supply

 

Any suggestions for the circuit...

One more thing when i connects the 220v ground to ir2110 ground using resistor the output comes for lamp. But, my load is actuator coil which consumes large amount of current while switching occurs..

 

Don't see the point of R9,10 they will be shorted out by the transistors when working..

 

Sorry, for the wrong indication in the circuit. Those resistors are not present in real time hardware.