A motor drive signal is output to the motor in accordance with the limited motor current command.

A motor current command is limited to at least one of a positive current limit or a negative current limit, the positive and negative current limits being a function of motor velocity.

Parameter 1 =Motor current (LCR): Logic address 3204; signed decimal

By comparing outputs from the plurality of motor current detection circuits, it is judged whether the motor current detection circuit has failed.

The resulting digital signal is used to calculate motor current.

The invention further relates to a method and a circuit arrangement, by means of which the motor current of a stepper motor can be controlled according to load angle in such a way that the current consumption of the motor is relatively low.

At the motor loss increase point, increase of the amplitude of the motor current increases the copper loss in the 3-phase coil of the AC motor.

Motor current is measured at predetermined pump pressures and flow rates to create calibration tables relating motor current to pump pressure.

According to the invention the shunt resistor (SH) is located in the free-wheeling circuit (4) in order to detect free-wheeling current (IF) which is taken as a measure for determining the load current (motor current IM).

According to the invention, the engine current (I) is observed for a period of time (t).

Each of the unipolar control circuits comprises a solid state switch (12) located between a motor current input and the source of direct current.

The current observer observes a motor current of the motor at a sampling rate.

The synchronous motor: DC motor (direct current), brushless, etc.

A motor current sensor (22) senses an actual current of the electric motor (14) and generates a signal indicative of the actual motor current.

An AC motor is an electric motor driven by an alternating current (AC).