# Variable (Freq. and Voltage) AC Power Supply

I am working on project called "Polarization Modulator". Idea is the having sinusoidal current on the inductor.(100uH) Frequency ( 500Hz - 2500Hz ) and current (peak current) (0A - 10A) on the inductor should be adjustable. I have 28V power supply only. I tried to use H - Bridge with NMOS but it has some problems. Hardest point for this project is @2500 Hz. @2500Hz ZL = 1.57Ohm. In order to get 10A peak, i need at least 17VAC. So, frequency changes mean VAC changes. Lower frequency >> @Constant VAC >> Higher Peak Current

In summary; 28VDC to adjustable frequency and AC Voltage Converter that can give at least 10A peak current.

Is that resolvable ? Worth to start on this project ? Any different ideas are welcome

( I newly graduated from university )

I have Adjustable sine wave generator (0V - 1V) (1Hz - 5Mhz )

Thank you

• Sounds like a fairly large audio amplifier (perhaps Class D) will do most of what you want. – Brian Drummond Feb 10 '17 at 14:18
• So, what were the problems with your H bridge - it seems to me that if you want help, the easiest answer is to improve on what you have done to fix the "problems". Also, it might be a good idea to explain what you are trying to build in case the "wheel" already exists. – Andy aka Feb 10 '17 at 16:10
• @BrianDrummond sounds ok. I have 2500W class D amplifier. I will try that. – Firat Dagkiran Feb 11 '17 at 12:38
• @Andyaka Problems occurs after 1.2kHz. First, top 2 NMOSs are gettin too hot. To get pure sinusoidal waveform on the inductor, i have to use Capacitors parallel with inductor and it cause the capacitors too hot. And the company only uses 28V and i couldn't find DC-DC Buck converter that i can play with it's output voltage. I was using XL4015 with DAC ( MCP4921 ) to play it's output voltage but it is only 75W which is not enoug for this projec – Firat Dagkiran Feb 11 '17 at 12:44