Motor device for a switch drive of an electric switch

1. A motor assembly for a switch drive of an electric switch, the motor assembly comprising:

a brushless three-phase motor;

an electronic controller for controlling said brushless three-phase motor, said electronic controller having:

a rectifier for rectifying a supply voltage of the motor assembly when the supply voltage is an AC voltage and for polarity reversal protection when the supply voltage is a DC voltage;

a voltage-measuring meter for detecting a rectifier output voltage of said rectifier;

a switch for generating a pulse-width-modulated AC drive voltage for said brushless three-phase motor from the rectifier output voltage; and

a further controller for actuating said switch depending on the rectifier output voltage.

2. The motor assembly according to claim 1 , wherein said electronic controller has a current-measuring meter for detecting a motor current flowing between said switch and said brushless three-phase motor.

3. The motor assembly according to claim 1 , wherein said electronic controller has a galvanic isolator for galvanically isolating said brushless three-phase motor from said electronic device.

4. The motor assembly according to claim 3 , wherein said galvanic isolator has a relay or a contactor for galvanically isolating said brushless three-phase motor from said electronic controller.

5. The motor assembly according to claim 1 , wherein said further controller has an input, via which input signals from at least one external apparatus are supplied to said further controller.

6. The motor assembly according to claim 5 , wherein the input signals from a limit switch for detecting an end position of the switch drive are supplied to said further controller via said input.

7. The motor assembly according to claim 1 , wherein said further controller has an output, via which output signals are output to at least one external apparatus by said further controller.

8. The motor assembly according to claim 1 , wherein said switch has an electronic switching component for each phase of said brushless three-phase motor, said electronic switching component being actuable in pulse-width-modulated fashion by said further controller.

9. A method for operating a motor assembly having a brushless three-phase motor and an electronic controller for controlling the brushless three-phase motor, the electronic controller having a rectifier unit, a voltage-measuring meter, a switch, and a further controller, which comprises the steps of:

rectifying a supply voltage of the motor assembly by the rectifier unit when the supply voltage is an AC voltage and polarity reversal protection is provided when the supply voltage is a DC voltage;

detecting a rectifier output voltage by the voltage-measuring meter;

generating a pulse-width-modulated AC drive voltage for the brushless three-phase motor from the rectifier output voltage by the switch;

actuating the switch by the further controller depending on the rectifier output voltage.

10. The method according to claim 9 , which further comprises generating pulse width modulation signals by the further controller for each phase of the brushless three-phase motor, duty cycles of the pulse width modulation signals being reciprocally proportional to an amplitude of the rectifier output voltage.

11. The method according to claim 9 , which further comprises generating pulse width modulation signals by the further controller for each phase of the brushless three-phase motor, duty cycles of the pulse width modulation signals having been matched to a setpoint value for a power of the brushless three-phase motor.

12. The method according to claim 9 , wherein:

an amplitude threshold value is preset;

an amplitude of a motor current flowing between the switch and the brushless three-phase motor is detected; and

the brushless three-phase motor is switched off when a detected amplitude of a motor current exceeds an amplitude threshold value.

13. The method according to claim 9 , wherein:

a time threshold value is preset;

a time period during which a motor current flows between the switching unit and the brushless three-phase motor is detected; and

the three-phase motor is switched off when the time period exceeds the time threshold value.