n.yashodhar

I am actually designing the power driver circuit for an electric bike using switched reluctance motor. I started designing a converter named power split converter. I designed the snubber circuit for the power mosfets. MY motor draws a 72V and 10.5A. I chose IRPF254 as my power MOSFET and MUR1560 as my free wheeling diode. This diode is a fast recovery diode. My RC snubber circuit has values of 1.1uF and 30ohm/6W.

Now in a power split converter i have two capacitors across the power supply which shud divide the voltage into equal halves. I started simulating this circuit in NI-multisim. but the complication is the INDUCTANCE of the field or stator coil changes with position of the rotor. I am not knowing how to simulate it. Can u please suggest me how to do tht?? and when i am simulating with a L value of 15mH which can be the maximum possible inductnace the required capactor across supply is about 100mF in simulation. This value of C is quite high. Can u suggest how to design the circuit rather than giving a trail and error method?? I have designed the position detection circuit and the PWM circuit for triggering. The frquency used to trigger the MOSFETs is 8khz. The trigger pulse is about 10V. What is the problem i am facing??

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