This thesis presents the process of development of an integrated starter-generator controller. Integrated starter-generator is a motor, that can function as a starter to start a petrol engine or as a generator, which produces electricity. For controlling this type of motor, the electronics must also be combined (inverter and regulator).
Controller for a brushless motor (inverter) is a circuit that replaces brushes in brushed motors. Brushed motors are used with a commutator, for switching the current in the motor. Here they are replaced with transistors. This reduces losses in the motor and brush wear.
In the vehicle, the regulator regulates the voltage that is generated by the generator. This motor will be able to achieve rotational frequencies of up to 10000 min-1, which poses a problem since the voltage generated rises linearly with rotational frequency and can achieve very high voltages. For reducing this voltage, the regulator short circuits the winding of the generator. This causes the current to bypass the battery.
The whole system is also functional without the battery, which means that the generator must produce enough voltage at 400 min-1. For raising the voltage at lower speeds the winding of the motor and the inverter are used as a switch converter.
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