This disclosure describes a control circuit to manage the energy flow for an integrated motor generator (IMG), such as an integrated starter generator (ISG) system. The circuit regulates the output voltage of the IMG when the IMG operates in generator mode. The circuit includes an additional switch for each phase connected in anti-series with the half-bridge circuit for the phase, e.g., the drain of the additional switch connects to the drain of the high-side switch. When the ISG is in generator mode, the additional switches are controlled, e.g., to charge the battery at a constant voltage and current throughout the speed range of the ISG (i.e. high rpm and low rpm). In generator mode, the high-side switches may be turned off, which configures the high-side switches to act as a diode and block battery discharge for low rpm operation when the phase voltages are lower.

A motor drive includes a rectifier bridge, which rectifier bridge is connected to an DC link, which is connected to an inverter bridge having phase outputs configured to be connected to an elevator motor, as well as a drive control controlling the semiconductor switches of the inverter bridge. The inverter bridge has upper semiconductor switches of the upper side connected to plus of the DC link and lower semiconductor switches of the lower side connected to minus of the DC link, the upper semiconductor switches are semiconductor switches without desaturation- and/or over-current protection whereas the lower semiconductor switches comprise a desaturation- and/or over-current protection, or vice versa. The drive control includes an earth fault control circuit which is configured to establish an earth fault test, in which each single semiconductor switch comprising a desaturation- and/or over-current protection is switched through, only one at a time, over a test time period, whereby the earth fault control circuit is configured to enable start of the motor drive only if the earth fault test has not lead to a tripping of the desaturation- and/or over-current protection of one of the semiconductor switches.

It is an object to provide a power conversion device and a ground fault location diagnosis method for determining ground fault locations on a motor and a cable and notifying a user or an external device or system of a determination result even when ground faults of a plurality of phases occur at locations close to each other. In order to achieve the above object, the power conversion device includes a ground fault current measurement unit, an interphase short-circuit current measurement unit, and a ground fault location determination unit. The ground fault current measurement unit turns on all the switches of either upper arms or lower arms of three half- bridge circuits, and measures output current values of a plurality of phases generated during the ON period. The interphase short-circuit current measurement unit turns on a switch of an upper arm of one phase of the three half-bridge circuits and a switch of a lower arm of a phase different from the one phase, and measures output current values of a plurality of phases generated during a period of time for which both the switches are ON. The ground fault location determination unit determines a ground fault location based on the output current values measured by the ground fault current measurement unit and the output current values measured by the interphase short-circuit current measurement unit.

A circuit for ground disconnection protection is provided herein. In an embodiment, the circuit includes power transistor elements in a common-source arrangement coupled between a first ground and a second ground. The power transistor elements are configured to turn on during a ground disconnection event in an electric motor system. This allows a current to pass between the first ground and the second ground, bypassing a control circuit.

A fault-tolerant power system architecture for aircraft electric propulsion. The fault-tolerant systems continue to operate in the event of the failure of (or one or more faults within) some component. The fault-tolerant design enables the system to continue its intended operation, possibly at a reduced level, rather than failing completely, when some part of the system fails. When a turn-to-turn fault in an AC motor is detected, a motor controller will short three top or three bottom switches in the inverter together (effectively shorting the associated stator windings) to divert fault current from the motor windings to the motor controller, where cooling is available. Also, when a fault in or at the input to a motor controller is detected, the motor controller cuts off power to the motor by issuing a command that causes an upstream contactor with high-voltage DC bus input to open.

Methods and apparatuses for detecting an open load condition for a load. The load is coupled to a power source at a high side and to a ground at a low side through at least one switch, the load has a first end and a second end, a first voltage at the first end is kept constant. A switch is controlled by a PWM signal. After the switch is turned off by the PWM signal, the voltage associated with the second end of the load is measured. In one embodiment, a change of the second voltage during a predefined delay is compared with a predefined voltage threshold. In another embodiment, the time it takes for the change of the second voltage to reach a predefined voltage threshold is compared with a predefined time threshold.

An electrical current flowing in a selected one of a plurality of electric motors (51, 52, 53) connected to and supplied from a power supply, wherein a current measuring device (46) is arranged in a connection between the power supply and the plurality of electric motors, is determined. Non-selected electric motors are controlled to be temporarily disconnected from the power supply, and then a current measurement is performed by the current measuring device, while the non-selected electric motors are temporarily disconnected from the power supply. Thus, this current measurement is indicative of the electrical current flowing in the selected electric motor. When the current measurement has been performed, the non-selected electric motors are again controlled to be reconnected to the power supply. In this way, the current drawn by individual motors can be determined with the use of only one current measuring device, so that additional costs can be avoided.

The present disclosure provides an image device. The image device may include a camera lens, one or more stepper motors to drive the camera lens, one or more H-bridge circuits configured to control at least one of the one or more stepper motors, and a lens-identification circuit connected with the one or more H-bridge circuits, wherein the lens-identification circuit includes an impedance network of which an impedance value corresponds to a type of the camera lens.

A protection device provided between a synchronous motor having a plurality of windings and a motor driving device for driving the synchronous motor includes: a switching unit for making and breaking the connection between the motor driving device and the synchronous motor; a dynamic brake circuit including resistors and switches, to short-circuit the plurality of windings between the switching unit and the synchronous motor via the resistors; and a control device for controlling the switching unit and the dynamic brake circuit. The control device controls the switches in the dynamic brake circuit to short-circuit the plurality of windings, and then controls the switching unit to cut off the connection between the motor driving device and the synchronous motor.

A power converter includes a first inverter, a second inverter, and a switching circuit including first and second switching elements. In a state in which, in the first inverter, potentials at a first node in a high side and a second node in a low side are equal to each other, and potentials at first ends of two-phase windings of n-phase windings with n being an integer of 2 or more are equal to each other, two-phase windings are energized using two legs connected to second ends of the two-phase windings of n legs of the second inverter while performing switching operations on the first and second switching elements of the switching circuit at a predetermined duty ratio.