An elevator system drive includes: an electric machine: a first converter electrically connected to an alternating current source and the electric machine: a drive controller controlling the drive: a drive safety circuit unit electrically connected to a safety circuit of the elevator system, to a controller of the elevator system, and to the drive controller; and at least one mechanical brake that is closed by a brake closing command from the elevator system controller. The drive safety circuit unit operates in a first operating state wherein it transmits an emergency stop command coming from the elevator system safety circuit directly and without delay to the first converter, and operates in a second operating state wherein it relays a modified emergency stop command coming from the elevator system safety circuit, with a delay, to the first converter to ensure safe braking of the elevator system even if the mechanical brakes fail.

A semiconductor device of an embodiment includes a first trench extending in a first direction in a silicon carbide layer; a second trench and a third trench adjacent to each other in the first direction; a first silicon carbide region of n type; a second silicon carbide region of p type on the first silicon carbide region; a third silicon carbide region of n type on the second silicon carbide region; a fourth silicon carbide region of p type between the first silicon carbide region and the second trench; a fifth silicon carbide region of p type between the first silicon carbide region and the third trench; a gate electrode in the first trench; a first electrode, part of which is in the second trench, the first electrode contacting the first silicon carbide region between the fourth silicon carbide region and the fifth silicon carbide region; and a second electrode.

A wireless power transfer arrangement for an elevator car of an elevator is presented. The wireless power transfer arrangement comprises primary winding units distantly arranged with respect to each other at first positions of an elevator shaft along which the elevator car is configured to be moved, at least one secondary winding unit arranged to the elevator car. Each one of the primary winding units and the at least one secondary winding unit are arranged so that there is a gap between said winding units for enabling movement of the secondary winding unit with respect to the primary winding units and for establishing an inductive coupling between said winding units whenever said winding units are arranged to face each other at one of the first positions.

A semiconductor device of an embodiment includes a silicon carbide layer having first and second plane, the silicon carbide layer including trench having a first portion and a second portion, the second portion having a width smaller than the first portion, an n-type first silicon carbide region, a p-type second silicon carbide region between the first silicon carbide region and the first plane, a p-type third silicon carbide region between the second silicon carbide region and the first plane and having a p-type impurity concentration lower than the second silicon carbide region, an n-type fourth silicon carbide region between the third silicon carbide region and the first plane, and an n-type fifth silicon carbide region between the second portion and the second silicon carbide region and having an n-type impurity concentration higher than the first silicon carbide region; and a gate electrode in the trench.

A semiconductor device according to an embodiment includes: a silicon carbide layer; a silicon oxide layer; and a region disposed between the silicon carbide layer and the silicon oxide layer and having a nitrogen concentration equal to or more than 1×10.sup.21 cm.sup.−3. A nitrogen concentration distribution in the silicon carbide layer, the silicon oxide layer, and the region have a peak in the region, a nitrogen concentration at a first position 1 nm away from the peak to the side of the silicon oxide layer is equal to or less than 1×10.sup.18 cm.sup.−3 and a carbon concentration at the first position is equal to or less than 1×10.sup.18 cm.sup.3, and a nitrogen concentration at a second position 1 nm away from the peak to the side of the silicon carbide layer is equal to or less than 1×10.sup.18 cm.sup.−3.

The invention relates to an elevator system comprising: an elevator car; at least one motor operable in two modes wherein in the first mode the at least one motor is consuming electrical energy and in the second mode the at least on motor is generating electrical energy; at least one rechargeable battery coupled to the at least one motor; wherein the at least one rechargeable battery is configured to be charged with an energy generated by the at least one motor when the motor is in the second mode.

A power supply circuit of a passenger conveyor converts includes an electrolytic capacitor and a control power supply device configured to supply an electric power to a charging circuit configured to charge the electrolytic capacitor. A storage battery is disposed between a converter and an inverter in parallel with the electrolytic capacitor. When an operation of the passenger conveyor is stopped in response to a key operation, the power supply to the control power supply device is shut off. When the operation of the passenger conveyor is resumed in response to a key operation, a DC electric power charged in the storage battery is supplied to the inverter, to thereby allow the passenger conveyor to resume the operation.

An elevator drive system (40) includes a permanent magnet (PM) synchronous electric motor (34) including a plurality of phases and a plurality of motor drives (55, 58) electrically connected to the PM synchronous electric motor. Each of the plurality of motor drives is operatively connected to a corresponding one of the plurality of phases. The plurality of motor drives is configured and disposed to deliver a torque current divided equally between each of the plurality of phases and independently deliver flux current to the corresponding one of the plurality of phases.

The arrangement comprises a drive driving an electric motor, a contactor and a control circuit connecting a control coil of the contactor to a power supply. The control circuit comprises a manual control part provided with a manually operated first switch, and an electronical control part provided with an electronically operated second switch and a processor controlling the second switch. The first switch and the second switch are connected in series in the control circuit with the power supply and the control coil of the contactor so that de-energization of the control coil of the contactor may be done either by the first switch or by the second switch.

A motor control apparatus includes control circuitry and rotation direction adjusting circuitry. The control circuitry is configured to output, in accordance with a phase sequence with respect to a motor, a drive command signal which is generated based on a motor rotation signal output from a motor rotation detector to control the motor. The rotation direction adjusting circuitry is configured to match the phase sequence with rotation direction information included in the motor rotation signal if a first trouble signal showing excessive motor current or excessive motor speed is input via an operation unit.