Circuit breaker unit

A method for operating a circuit breaker connecting a group of electrical systems, the group of electrical systems includes at least one first electrical system and one second electrical system, the method comprising:

• providing one variable first resistance, one variable second resistance, and one variable third resistance, the first resistance is directly or indirectly connected to the first electrical system and the second resistance is directly or indirectly connected to the second electrical system, the third resistance is connected to a reference potential;
• providing a common node, all three resistances are in each case directly or indirectly connected at the common node;
• monitoring, at a control unit, voltages of the electrical systems and/or at least one current through the circuit breaker;
• and
• when a fault case of overvoltage or undervoltage in one of the electrical systems or overcurrent occurs, adjusting values of the resistances by way of the circuit breaker such that the electrical systems are disconnected from one another and that the voltage in a fault-free electrical system remains within predetermined limits, and
• wherein the adjustment of the values of the resistances such that the electrical systems are disconnected from one another and that the voltage in the fault-free electrical system remains within predetermined limits includes at least one of the resistances being actuated at least occasionally depending on values, which were detected or provided in predetermined time steps, for the voltage of the fault-free electrical system and/or for the voltage of the faulty electrical system and/or for the at least one current, such that the at least one resistance functions as a continuous linear controller.

A control unit for operating a circuit breaker that connects a group of electrical system, the group of electrical systems includes at least one first electrical system and one second electrical system, the control unit executing a method comprising:

• monitoring voltages of the electrical systems and/or at least one current through the circuit breaker, wherein a first variable resistance is directly or indirectly connected to the first electrical system and a second variable resistance is directly or indirectly connected to the second electrical system, a third variable resistance is connected to a reference potential, and all three resistances are in each case directly or indirectly connected at a common node;
• and
• when a fault case of overvoltage or undervoltage in one of the electrical systems or overcurrent occurs, adjusting values of the resistances by way of the circuit breaker such that the electrical systems are disconnected from one another and that the voltage in a fault-free electrical system remains within predetermined limits, and
• wherein the adjustment of the values of the resistances such that the electrical systems are disconnected from one another and that the voltage in the fault-free electrical system remains within predetermined limits includes at least one of the resistances being actuated at least occasionally depending on values, which were detected or provided in predetermined time steps, for the voltage of the fault-free electrical system and/or for the voltage of a faulty electrical system and/or for the at least one current, such that the at least one resistance functions as a continuous linear controller.