摘要:
In a control system and a method for operating a permanent-magnet electrical machine, when the electrical machine is switched off after one of a functional computer and a monitoring computer of the control system has identified a fault, in order to reduce the braking torque of the electrical machine, which is switched-off but still rotating an output stage of the control system is subjected to a three-phase short circuit if the rotation speed D1 does not fall below a definable limit value GR1 or if a voltage U_DC of the output stage (2) exceeds a limit value Umax, and when the rotation speed D1 is below the definable limit value GR1 and a voltage U_DC of the output stage does not exceed a limit value Umax, all the circuits breakers (2o1, 2o2, 2o3 2u1, 2u2, 2u3) of the output stage (2) are opened in order to fully disconnect the electrical machine from the output stage.
摘要:
The invention relates to a diesel-electric drive system comprising a permanently excited synchronous generator (4), which is mechanically coupled to a diesel motor (2) on the rotor side and has an electrical connection to a voltage link converter (6) on the stator side, said converter having a respective self-commutated pulse-controlled converter (12, 14) on the generator and load sides. The converters are interconnected on the d.c. voltage side by means of a d.c. link (18). The system also comprises a braking resistor (20), which can be electrically connected to said d.c. link (18). According to the invention, a multi-phase braking resistor assembly, which can be electrically connected in series to the multi-phase stator winding system (74) of the permanently excited synchronous generator (4) by means of a multi-phase actuator (32), is provided as the braking resistance. This permits the provision of a diesel-electric drive system which no longer requires an additional brake attenuator and in which the mode can be changed between generator mode and operating mode, the speed of said diesel motor being freely set in the operating mode.
摘要:
An inverter that supplies a desired primary voltage (v1) to an induction motor, a current detector that detects a primary current (i1) from the inverter to the induction motor, a voltage designation value calculating unit that generates a voltage designation value (v1*) for generating the voltage v1, an idling-time speed estimating unit that calculates an estimate value (ωr#) of the rotation speed when the induction motor is idling, and a sequence circuit that commands the operations of these units are provided. The idling-time speed estimating unit switches a method for deriving the estimate value on the basis of a current value in the case where a short circuit is generated between windings when the induction motor is idling.
摘要:
The following invention is an electromechanical system (1) that is to be connected to an electricity supply (7), comprising: an electric machine (2) that can operate as an independent generator with a rotating shaft, and a switching system (9) allowing i) in the first configuration, the electric machine to operate as a motor in the case where the connected device (4) is normally driven or as a generator in the case where the coupled device is normally driving, and ii) in the second configuration, the electric machine to operate as an independent generator, the electrical energy generated by the electric machine (2; 22) being dissipated in the machine and in a dissipative load (13).
摘要:
A variable speed wind turbine having a doubly fed induction generator (DFIG), includes an exciter machine mechanically coupled to the DFIG and a power converter placed between a rotor of the DFIG and the exciter machine. Thus, the power converter is not directly connected to the grid avoiding the introduction of undesired harmonic distortion and achieving a better power quality fed into the utility grid. Moreover, the variable speed wind turbine includes a power control and a pitch regulation.
摘要:
A machine for operating on a glass bottle. A carriage is displaceable by a servo motor having three lead lines. The rotation of the servo motor is stopped when power has been removed by shorting regenerative resistors to the three motor leads. The stopped servo motor is held at its stopped position by connecting a direct current power supply to two of the three servo motors.
摘要:
A drive system with an electric motor is described, which includes an integrated armature short-circuit brake and a mechanical brake. If the electric motor cannot be controllably slowed down, a control signal is applied at an activation time to the integrated armature short-circuit brake and the mechanical brake, and the armature short-circuit brake is switched off when reaching a thermal load limit for the electric motor or the control electronics.
摘要:
A system and method for protecting a motor drive unit from an associated motor includes a motor drive unit protection system. The motor drive unit protection system includes at least one switch configured to be connected between a motor drive unit and a plurality of motor leads of the motor driven by the motor drive unit. The motor drive unit protection system also includes a controller configured to monitor the motor drive unit or the motor to determine a fault condition indicative of the motor potentially operating as a generator. Upon determining the fault condition, the controller is configured to cause the at least one switch to connect the plurality of motor leads together to protect the motor drive unit from the motor when the motor is operating as a generator.
摘要:
A braking module includes a braking load, an input terminal, an output terminal, and control logic. The input terminal is adapted to receive a motor drive signal. The control logic is adapted to receive a motor enable signal, couple the output terminal to the input terminal responsive to the motor enable signal being asserted, couple the output terminal to the braking load responsive to the motor enable signal being deasserted, and prevent the coupling of the output terminal to the input terminal responsive to a temperature of the braking module exceeding a predetermined disable set point. A method for controlling a motor includes coupling a drive lead carrying a motor drive signal to a motor lead of the motor responsive to a motor enable signal being asserted. The motor lead is coupled to a braking load responsive to the motor enable signal being deasserted. The coupling of the drive lead to the motor lead is prevented responsive to a temperature of the braking load exceeding a predetermined disable set point.
摘要:
A circuit configuration for driving an electric motor, in particular of a washing machine, includes power switches connected to connection terminals of the electric motor and to a voltage intermediate circuit. A driver circuit is connected to the voltage intermediate circuit and to the power switches. A control unit, in particular a micro controller, is connected to the driver circuit. The control unit generates control signals for controlling at least one rotation speed of the electric motor. The driver circuit generates short-circuit control signals for driving the power switches, which bring about a short circuit of the connection terminals connected to the power switches, independently of the control signals from the control unit. The driver circuit generates the short-circuit control signals as a function of a detection of an overvoltage of the voltage intermediate circuit over a desired voltage range. A method for controlling an electric motor is also provided.