| 摘要 |
The control circuit of an electric motor, which has at least one phase supplied with high voltage and has a defined high-voltage zone, is provided with a control for the supply current of the phase with a setpoint-value current, and has devices for measuring the supply current which generate a first analog signal whose value corresponds to the measured current, an electronic control unit being disposed in a low-voltage zone, and having an analog-to-digital converter for converting the first analog signal or another analog signal acting as the first analog signal, into a corresponding digital signal which is supplied to the electronic control unit. The measuring devices are formed by a bleeder resistor, which is disposed in series with the phase, as well as by a differential amplifier whose two inputs, respectively, are connected to two contacts of the bleeder resistor. The analog-to-digital converter is located in the high-voltage zone a galvanic separating element is situated between the analog-to-digital converter and the electronic control unit. The control circuit has, inter alia, a voltage converter which, within the high-voltage zone, provides a floating low voltage which supplies the analog-to-digital converter. |
