Efficiency Increasing by a Variable DC Link Voltage in Combination with a Bang-Bang Controlled Inverter for an Automotive Application

Inhalt:
Main losses in inverters are primary depending on the power electronic switching. By adjusting the DC link voltage the losses can be decreased due to the less DC link voltage which is switched. Furthermore, even more efficiency can be reached, by modifying the modulation method of the inverter. By using of the most popular modulations method, the PWM, the switching frequency of the inverter is fixed. Due to the using of a bang-bang current controlled inverter the switching frequency is mainly depending from the back EMF voltage of the machine, the DC link voltage and the motor inductance. By adjusting the DC link voltage it is possible to minimize the switching frequency.