A motor control apparatus for securing insulation performance includes: a temperature sensor detecting a temperature of a motor; an altitude detection means providing information on an altitude at which the motor is positioned; and a controller including a motor output map having a plurality of groups of map data in which motor output limit rates depending on temperatures of the motor are pre-stored for each preset altitude section, selecting one group of map data corresponding to the information on the altitude provided by the altitude detection means, and determining a motor output limit rate by applying the temperature detected by the temperature sensor to the selected group of map data.

A motor control apparatus for securing insulation performance includes: a temperature sensor detecting a temperature of a motor; an altitude detection means providing information on an altitude at which the motor is positioned; and a controller including a motor output map having a plurality of groups of map data in which motor output limit rates depending on temperatures of the motor are pre-stored for each preset altitude section, selecting one group of map data corresponding to the information on the altitude provided by the altitude detection means, and determining a motor output limit rate by applying the temperature detected by the temperature sensor to the selected group of map data.

A main power supply having a large capacity and a backup power supply having a small capacity are switchable by a power supply switching determination unit in a system. A motor control device drives a motor by the main power supply or the backup power supply. A drive control unit outputs a drive signal, calculated by feedback control of the current detection value with respect to the current command value, to an inverter circuit. When the power supply switching determination unit switches from the main power supply to the backup power supply, the drive control unit moves from a normal control using the main power supply to a backup control that restricts an electric power consumption and prevents the backup power supply from stopping.

A main power supply having a large capacity and a backup power supply having a small capacity are switchable by a power supply switching determination unit in a system. A motor control device drives a motor by the main power supply or the backup power supply. A drive control unit outputs a drive signal, calculated by feedback control of the current detection value with respect to the current command value, to an inverter circuit. When the power supply switching determination unit switches from the main power supply to the backup power supply, the drive control unit moves from a normal control using the main power supply to a backup control that restricts an electric power consumption and prevents the backup power supply from stopping.

A power module for driving a motor includes: a positive bus input voltage terminal; a phase terminal for each motor phase; an inverter including a half bridge for each motor phase, each half bridge including a high-side power switch electrically coupled between the positive bus input voltage terminal and respective phase terminal, and a low-side power switch electrically coupled between the respective phase terminal and ground; a first driver circuit for driving a gate terminal of each power switch; a protection switch electrically coupled in series between the positive bus input voltage terminal and each high-side power switch, and having a greater short-circuit withstand time and a lower short-circuit current level compared to each inverter power switch; and a second driver circuit for turning on the protection switch during normal operation and turning off the protection switch in response to a detected short circuit condition.

A digital positioner for a valve includes a valve controller configured to obtain a set point value for a valve travel of a valve, and generate a pulse-width modulated current signal based on the set point value. The digital positioner also includes a current-to-pressure converter configured to receive the pulse-width modulated current signal from the valve controller, convert the pulse-width modulated current signal to a pulse-width modulated pressure signal, and provide the pulse-width modulated pressure signal to a pneumatic actuator in the valve to adjust a position of the valve.

A digital positioner for a valve includes a valve controller configured to obtain a set point value for a valve travel of a valve, and generate a pulse-width modulated current signal based on the set point value. The digital positioner also includes a current-to-pressure converter configured to receive the pulse-width modulated current signal from the valve controller, convert the pulse-width modulated current signal to a pulse-width modulated pressure signal, and provide the pulse-width modulated pressure signal to a pneumatic actuator in the valve to adjust a position of the valve.

A method for operating an electrical circuit arrangement comprising an electrical circuit and an electrical machine, wherein when at least one triggering criterion is fulfilled the electrical machine is switched via the electrical circuit to a freewheeling, after which a time duration is determined in dependence on at least one measurement value describing a change in the stator current in the electrical machine, and the electrical machine is operated in the freewheeling for this duration and then it is switched via the electrical circuit to an active short circuiting.

A method for operating an electrical circuit arrangement comprising an electrical circuit and an electrical machine, wherein when at least one triggering criterion is fulfilled the electrical machine is switched via the electrical circuit to a freewheeling, after which a time duration is determined in dependence on at least one measurement value describing a change in the stator current in the electrical machine, and the electrical machine is operated in the freewheeling for this duration and then it is switched via the electrical circuit to an active short circuiting.

A motor control apparatus excites an excitation phase targeted for excitation among a plurality of excitation phases of a motor. The motor control apparatus, in a state in which a rotor of the motor is stopped, excites an excitation phase corresponding to a stop position of the rotor among the plurality of the excitation phases, and measures a physical quantity which changes in accordance with an inductance of at least one of a plurality of coils configuring the plurality of excitation phases. The motor control apparatus estimates a temperature of the rotor from a measurement value of the measured physical quantity, and decides a parameter value for control of the motor based on the estimated temperature.