A semiconductor device has an A/D converter configured to convert an analog signal representing a current flowing in a control target into a digital signal, an overcurrent determination unit configured to, based on the analog signal, determine that an overcurrent has occurred in the control target when the current flowing in the control target has exceeded an overcurrent threshold, and determine that the overcurrent has not occurred in the control target when the current flowing in the control target has not exceeded the overcurrent threshold, a drive control signal generation unit configured to generate a drive control signal for controlling driving of the control target so that the current flowing in the control target is equal to a target current, based on a conversion result of the A/D converter, and generate the drive control signal to reduce the current flowing in the control target when the overcurrent determination unit determines that the overcurrent has occurred, and an overcurrent threshold setting unit configured to set the overcurrent threshold based on the conversion result of the A/D converter and the target current.

The disclosure relates to an electric machine and in particular to the monitoring of the electric machine for the presence of a fault, (e.g., in the stator windings). A monitoring unit is provided, wherein the monitoring unit measures the multiphase electrical time signals transmitted from or to the machine and with the aid of a Hilbert filter determines substantially in real time the envelopes and the phase positions of the individual phases of the time signal. The envelopes corresponding to the different phases or the corresponding phase positions are compared with one another by way of forming differences and, in the event that one or more of the differences deviate(s) from a specified expectation value, the presence of a fault is inferred. The approach allows significantly increased operational reliability of the electric machine to be achieved in particular.

A motor control device performs driving control of a motor via a drive circuit that converts a power supply voltage of a direct current power supply into a drive voltage of the motor. The motor control device includes a voltage measurement circuit that measures the power supply voltage. The motor control device acquires a detection signal correlated with a current value that is output from a current detection circuit.

A motor control apparatus for controlling a power supply to an electrical motor (M) connected to an output terminal (3) of the motor control apparatus (1) comprising: an overcurrent protection circuit (1A) having a power switch (5) through which the electrical motor (M) receives an electrical load current (I.sub.L) and having a sensor component (4) connected in series with the power switch (5) and adapted to generate directly a voltage drop (ΔU.sub.4) corresponding to the current rise speed of the electrical load current (I.sub.L) flowing from an input terminal (2) of the motor control apparatus (1) via the sensor component (4) and the power switch (5) to the output terminal (3) and having a driver circuit (6) adapted to detect an occurring overcurrent depending on the voltage drop (ΔU.sub.4) generated by the sensor component (4) and/or depending on a voltage drop (ΔU.sub.5) along the power switch (5) and adapted to switch off said power switch (5) upon detection of an overcurrent within a switch-off period of less than one millisecond; and/or comprising a power supply control circuit (10) having a sensor component (9) adapted to measure at the input terminal (2) a supply voltage notified to a control unit (8) of the motor control apparatus (1) adapted to control an electrical power supplied to the electrical motor (M) depending on an operation mode of the electrical motor (M).

A compressor assembly includes a compressor motor having a main winding coupled with a line terminal to receive power from a line voltage source, and an auxiliary winding. The assembly includes first and second capacitors each coupled between the line terminal and the auxiliary winding, a first relay to selectively couple the first capacitor and the second capacitor in parallel, a second relay coupled to selectively inhibit the supply of power from the line voltage source to the auxiliary winding via the first capacitor, and a control circuit configured to close the first relay in response detection of excess load condition criteria, and to subsequently open the first relay in response to detection of normal load condition criteria. The excess load condition criteria and the normal load condition criteria each include at least one of a voltage of the main winding and a voltage of the auxiliary winding.

The internal temperate of a transistor is determined by detecting a voltage though a terminal of an integrated circuit that is also used by an overcurrent detection circuit of the integrated circuit for detecting an overcurrent condition of the system. The overcurrent detection circuit is coupled to a current electrode of the transistor through the terminal of the integrated circuit. A determination of internal temperature is based on a voltage measurement taken from the terminal during an on phase of the transistor. The voltage measurement is converted to a digital value and is used to determine an internal temperature of the transistor.

A motor drive device includes an inverter circuit to drive a motor, an inverter control device to control the inverter circuit, a gate-driving power supply to supply power to be used for driving the inverter circuit, a circuit pattern configured to connect the inverter circuit and the gate-driving power supply, a control power supply connected to the circuit pattern to supply power to be used for driving the inverter control device, and a thermal switch connected to the circuit pattern to interrupt power supply from the gate-driving power supply to the inverter circuit when a temperature of a winding of the motor exceeds a predetermined temperature.

An electric power conversion device includes: a first electric power conversion circuit, a current detection circuit, an electric power conversion circuit of field coil excite use, a control circuit, and detector which detects an induced electromotive force generated in the motor generator. In a case where an over current, is detected by the first electric power conversion circuit, the control circuit turns off a switching of a phase of the first electric power conversion circuit from which an over current s detected and a switching of the electric power conversion circuit of field coil excite use. After the value of an induced electromotive force by the motor generator falls below a predetermined value, the control circuit controls to stop a supply of electric power of all phases by the first electric power conversion circuit.

According to some embodiments, AC chopping circuit includes a switching circuit, a synchronizing signal generating circuit, a switch driving circuit and an auxiliary power supplying circuit. In some examples, the switching circuit are coupled to an AC power source and a load. In certain examples, the synchronizing signal generating circuit provides a synchronizing signal which is related to a polarity of the AC power source. In some examples, the switching circuit is controlled based at least in part on the synchronizing signal.

A control system for a hybrid electric powerplant of an aircraft can include a heat engine controller configured to receive one or more power settings and to determine a heat engine setting and an electric motor setting. The heat engine controller can be configured to use the heat engine setting to control a heat engine system as a function of the heat engine setting to control torque output by a heat engine. The heat engine controller can be configured to output the electric motor setting. The system can include an electric motor controller can be operatively connected to the heat engine controller. The electric motor controller configured to receive the electric motor engine setting from the heat engine controller and to control an electric motor system as a function of the electric motor setting to control torque output by an electric motor. The system can include a system protection module that can be part of or connected to the heat engine controller and can be configured to provide one or more protection commands to directly control one or more heat engine protection systems and one or more electric motor protection systems.