Hi all,
I am building an AC Induction Motor drive using a six switch inverter. I have a 540V / 5.5A supply, feeding a DC link capacitor of 30uF which in turn feeds the six switch inverter. The inverter outputs are connected to the motor which is rated at 550W, power factor 0.8. My switching frequency is 20kHz.
When I power on the circuit, the motor begins to spin, the power supply then goes into current limit mode and shuts off, then it recovers and the same thing happens again. If I connect a larger 235uF capacitance in parallel with the existing DC link capacitor, everything runs beautifully.
Does anyone have any suggestions as to why the system won't run at the lower capacitance value? I have worked through the procedure in this paper https://www.kalbeck.com/asset/630/Whitepaper SalconeBond.pdf and it suggests that I should see only 105mV of ripple on the DC rail and hardly any ripple current.
Thanks
I am building an AC Induction Motor drive using a six switch inverter. I have a 540V / 5.5A supply, feeding a DC link capacitor of 30uF which in turn feeds the six switch inverter. The inverter outputs are connected to the motor which is rated at 550W, power factor 0.8. My switching frequency is 20kHz.
When I power on the circuit, the motor begins to spin, the power supply then goes into current limit mode and shuts off, then it recovers and the same thing happens again. If I connect a larger 235uF capacitance in parallel with the existing DC link capacitor, everything runs beautifully.
Does anyone have any suggestions as to why the system won't run at the lower capacitance value? I have worked through the procedure in this paper https://www.kalbeck.com/asset/630/Whitepaper SalconeBond.pdf and it suggests that I should see only 105mV of ripple on the DC rail and hardly any ripple current.
Thanks