There is disclosed a fault ride-through system for use in a power system comprising a synchronous generator driven by a prime mover. The fault ride-through system comprises a mechanical switch connected in parallel with a dynamic power dissipater, wherein the dynamic power dissipater comprises a solid-state switch connected in series with a braking resistor. A controller is configured to control the mechanical switch and the solid-state switch to control the current through the braking resistor, based on received data indicative of one or more operation parameters of the power system.

The invention relates to a joint device, comprising an electric motor, an electrically controllable blocking apparatus), various control apparatuses, and a brake system, in the case of which brake system, in various alternatives, the brake system takes maximum energy from the system by means of active closed-loop/open-loop control or by triggering a (cycled) short circuit whenever possible and only triggers the mechanical blocking as a last resort in order to protect the mechanical and electrical system itself, but nevertheless ensures that the system is securely shut down after a maximum time.

The invention relates to a joint device, comprising an electric motor, an electrically controllable blocking apparatus), various control apparatuses, and a brake system, in the case of which brake system, in various alternatives, the brake system takes maximum energy from the system by means of active closed-loop/open-loop control or by triggering a (cycled) short circuit whenever possible and only triggers the mechanical blocking as a last resort in order to protect the mechanical and electrical system itself, but nevertheless ensures that the system is securely shut down after a maximum time.

The present disclosure relates to mechanical braking mechanisms used in electric motor applications. The present braking mechanisms may be configured as non-back-drivable mechanical brakes and provide immediate braking of the motors. According to one embodiment, a mechanical brake assembly for an electric motor may include a female disk having a curved groove and an abutment. The mechanical brake assembly further includes a male disk having a projection, the male disk being attached to a rotor of the electric motor. When the electric motor is energized, the projection of the male disk is allowed to rotate uninterrupted with the rotation of the rotor. However, when the electric motor is de-energized, the projection of the male disk travels within the curved groove of the female disk and abuts the abutment of the female disk, thereby stopping the rotation of the rotor of the electric motor.

The present disclosure relates to mechanical braking mechanisms used in electric motor applications. The present braking mechanisms may be configured as non-back-drivable mechanical brakes and provide immediate braking of the motors. According to one embodiment, a mechanical brake assembly for an electric motor may include a female disk having a curved groove and an abutment. The mechanical brake assembly further includes a male disk having a projection, the male disk being attached to a rotor of the electric motor. When the electric motor is energized, the projection of the male disk is allowed to rotate uninterrupted with the rotation of the rotor. However, when the electric motor is de-energized, the projection of the male disk travels within the curved groove of the female disk and abuts the abutment of the female disk, thereby stopping the rotation of the rotor of the electric motor.

A system includes a converter operatively connected to an alternating current (AC) power source and a direct current (DC) bus, an inverter operatively connected to a motor and the DC bus, and a controller. The converter includes a first plurality of switching devices in selective communication with each phase of the AC power source and the DC bus. The inverter includes a second plurality of switching devices in selective communication with each phase of the motor and the DC bus. The controller is operable to command dropping of a brake through a passive delay circuit responsive to an emergency stop condition for a load driven by the motor and reduce a voltage on the DC bus by dropping at least one phase of the AC power source and/or using a dynamic braking resistor prior to the brake physically dropping.

A system includes a converter operatively connected to an alternating current (AC) power source and a direct current (DC) bus, an inverter operatively connected to a motor and the DC bus, and a controller. The converter includes a first plurality of switching devices in selective communication with each phase of the AC power source and the DC bus. The inverter includes a second plurality of switching devices in selective communication with each phase of the motor and the DC bus. The controller is operable to command dropping of a brake through a passive delay circuit responsive to an emergency stop condition for a load driven by the motor and reduce a voltage on the DC bus by dropping at least one phase of the AC power source and/or using a dynamic braking resistor prior to the brake physically dropping.

A method for controlling an active short circuit in a permanent magnet excited electric machine, the method including checking if an activating of the active short circuit is requested, registering at least one further state parameter of the electric machine, determining, if the active short circuit is requested in the step of checking, if the at least one further state parameter has a critical value, and controlling the activating of the active short circuit as a function of the determining by sending a control signal to a device for short circuiting.

An elevator includes a manual active dynamic braking function, which elevator includes an elevator control for operating at least one elevator car in at least one elevator driveway between landing floors in response to elevator calls, an AC elevator motor, which is able to generate power in a generator mode, a motor drive connected to the elevator control for the regulation of the speed of the elevator motor, including a frequency converter, whereby the frequency converter of the motor drive includes a rectifier bridge and an inverter bridge with semiconductor switch circuits, which rectifier bridge and inverter bridge are connected via a DC link, the motor drive further including a drive controller at least to control the semiconductor switches of the semiconductor switch circuits of the inverter bridge to regulate the elevator motor to a reference speed, whereby the semiconductor switch circuits of the inverter bridge are provided with diodes connected anti-parallel to the semiconductor switches, the motor drive including a safety logic for cutting off control pulses to the semiconductor switches, at least during power outage, at least one elevator brake is located in connection with the elevator motor and/or with a traction sheave of the elevator motor, a manual brake release lever is functionally linked to the elevator brake, movable between a rest position and at least one operating position to release the elevator brake manually. The motor drive includes a bypass switch being arranged to operate the safety logic, as to enable dynamical braking of the elevator motor by connecting the semiconductors of the semiconductor switch circuits of the inverter bridge with the drive controller, and the motor drive includes a DC supply circuit connected with the DC link, which is arranged to feed DC power at least to the drive controller and to the bypass switch to enable dynamic braking control of the semiconductor switches. The manual brake release lever is functionally connected with the bypass switch and is arranged to operate the bypass switch, when it is moved away from its rest position. Alternatively, the elevator includes a manual actuator, such as a key switch, disposed in the same location with the manual brake release lever, whereby the manual actuator is arranged to operate the manual bypass switch.

A method for braking a motor in a high lift system of an aircraft, the high lift system comprising a central power drive unit for moving high lift surfaces arranged at a wing through providing rotational power by means of a transmission shaft to a plurality of drive stations operably coupled with the high lift surfaces; which power drive unit is operatively coupled to a controller and comprises at least one electric motor coupled therewith. The method includes determining a braking requirement for the at least one electric motor, measuring at least one of a current command to the motor and a current speed and direction of the at least one electric motor, based on the braking requirement, applying a braking command to the at least one electric motor, and reducing the braking command as the at least one electric motor comes to rest.