Control apparatus and corresponding method for controlling a high power electric motor, preferably of the order of megawatts, preferably of or associated with a shredding plant which is preferably usable for shredding very bulky and heavy objects and is provided with a rotating shredding member connected to the rotor of the electric motor, where a control circuit is configured to control the electric motor so that it can operate selectively in different operating modes.

The method for controlling a rotating electric machine according to the invention comprises a step of controlling the phase currents of the machine by means of a full-wave control (C). According to the invention, the full-wave control (C) is generated via a pulse width modulated signal of which the signal frequency is greater than an electric frequency of the machine. According to another feature, ascending or descending fronts (24, 25) of the pulse width modulated signal are synchronised with first and second crossings of first and second angular switching thresholds (S1, S2) by an electric position (θ) of the machine and a duty ratio (α) of the pulse width modulated signal is periodically refreshed to the signal frequency.

The present invention provides a method and a device for operating an electric machine for a soft changeover from a normal or free-wheel mode to an active short-circuit. To this end, a voltage with which the electric machine is actuated is first reduced in a defined manner to a predefined, preferably very low value and then the phase connections of the electric machine are short-circuited. Excessively high overcurrents, particularly overcurrents greater than the nominal current of the electric machine, can thus be avoided.

The present invention provides a device and a method for changing over an electric machine from the regular operating mode into the open-circuit mode. In order to avoid excessive increases in voltage and associated adverse effects on the electric machine and the other components, in particular batteries, a further control phase is introduced between the end of the regular operating mode and the freewheeling mode, during which further control phase the voltage at the terminals of the electric machine is continuously adjusted from the voltage previously set in the regular operating mode to the expected open-circuit voltage of the electric machine.

A motor control apparatus for a vehicle includes a data detector detecting driving data and a vehicle controller controlling a drive motor according to the driving data. The vehicle controller includes an acceleration generator determining a request torque and a request speed using the driving data and generating a request acceleration using the request torque and the request speed; a driving point determinator selecting an inductance control current map or a motor efficiency control current map according to the request acceleration and determining a current driving point according to the request torque and the request speed using the selected current map; and a motor controller controlling the drive motor using the current driving point.

Control apparatus and corresponding method for controlling a high power electric motor, preferably of the order of megawatts, preferably of or associated with a shredding plant which is preferably usable for shredding very bulky and heavy objects and is provided with a rotating shredding member connected to the rotor of the electric motor, where a control circuit is configured to control the electric motor so that it can operate selectively in different operating modes.

A battery powered fluid sprayer includes a reciprocating positive displacement pump, a power supply that includes a battery, an electric motor, a motor controller, a user-adjustment mechanism for setting a user-adjustable pressure threshold corresponding to system fluid pressure of the battery powered fluid sprayer, a pressure switch, and a power controller. The pressure switch generates a pressure signal indicative of whether the system fluid pressure is greater than the user-adjustable pressure threshold. The power controller is configured to control power of the battery powered fluid sprayer by providing operating power of the motor controller in response to the pressure signal indicating that the system fluid pressure is less than the user-adjustable pressure threshold, and not providing the operating power of the motor controller in response to the pressure signal indicating that the system fluid pressure is greater than the user-adjustable pressure threshold.

A thyristor starter accelerates a synchronous machine from a stop state to a predetermined rotation speed by sequentially performing a first mode of performing commutation of an inverter by intermittently setting DC output current to zero and a second mode of performing commutation of the inverter by induced voltage of the synchronous machine. A second controller controls the firing phase of a thyristor in a converter such that DC output current of the converter matches a current command value, based on a detection signal of a position detector. In the first mode, the current command value is set such that the current value is higher as the rotation speed of the synchronous machine is higher.

The present invention allows a communication mode in which to communicate with a detection section to be easily and conveniently changed in a motor control device. A slave device (90) includes: a network communication section (120) configured to communicate with a PLC (100) via a communication network; an FB signal obtaining section configured to obtain an FB signal from a detection section; and a setting communication section (140) configured to receive communication mode information of an FB through another communication path different from the communication network. The FB signal obtaining section includes a reconfigurable device and is capable of changing a communication mode of the FB signal obtaining section by reconfiguring the reconfigurable device. The slave device (90) reconfigures the reconfigurable device in accordance with the communication mode information in a case where the setting communication section (140) receives the communication mode information.

A thyristor starter accelerates a synchronous machine from a stop state to a predetermined rotation speed by sequentially performing a first mode of performing commutation of an inverter by intermittently setting DC output current of a converter to zero and a second mode of performing commutation of the inverter by induced voltage of the synchronous machine. In the thyristor starter, during a first time period from start of performance of the second mode to arrival of the induced voltage of the synchronous machine at a first voltage value, a phase control angle of the inverter is changed such that a value thereof becomes larger as a rotation speed of the synchronous machine becomes higher.