초록 ▼

The circuit configuration is used to drive an electrical drive unit. The circuit has a voltage source and a control circuit for voltage commutation connected between the voltage source and the electrical drive unit. In addition, the circuit includes a temperature evaluation circuit that monitors the

The circuit configuration is used to drive an electrical drive unit. The circuit has a voltage source and a control circuit for voltage commutation connected between the voltage source and the electrical drive unit. In addition, the circuit includes a temperature evaluation circuit that monitors the temperature of the control circuit. The temperature evaluation circuit uses the motor current of the electrical drive unit to determine the housing temperature of the power switch which has the greatest load.

대표청구항 ▼

[ I claim:] [1.] A circuit configuration for driving an electrical drive unit, comprising:a control circuit through which a current is supplied to the electrical drive unit, said control circuit having a current bridge and a bridge driver connected to said current bridge; anda temperature evaluation

[ I claim:] [1.] A circuit configuration for driving an electrical drive unit, comprising:a control circuit through which a current is supplied to the electrical drive unit, said control circuit having a current bridge and a bridge driver connected to said current bridge; anda temperature evaluation circuit determining from the current supplied to the electrical drive unit a temperature of said current bridge and outputting a temperature-dependent output signal, said temperature evaluation circuit including a squarer, an adder and an RC filter having a time constant equal to a thermal time constant of said control circuit, said temperature evaluation circuit being connected to receive a motor current value of the electrical drive unit, the temperature-dependent output signal being formed by squaring the motor current value with the squarer to form a square of the motor current, integrating the square of the motor current with said RC filter to form an integral, and adder, to the integral a variable dependent on an ambient temperature.