Abstract: The invention relates to an elevator drive unit for managing a regenerative power of an elevator system. The elevator drive unit comprises: first terminals for connecting the elevator drive unit to the mains; second terminals for connecting the elevator drive unit to an elevator hoisting motor; a frequency converter for enabling a bidirectional transfer of power between the mains and the elevator hoisting motor; and a control unit. The control unit is configured to: obtain an indication representing a detection of a special operational situation of the elevator system, introduce a non-zero power limit specific to the detected special operational situation of the elevator system, and control the frequency converter to limit supply of the regenerative power from the elevator hoisting motor to the mains to the power limit. The invention relates also to an elevator system and a method for managing a regenerative power of an elevator system.

Abstract: A method for dynamic braking of a permanent magnet motor, and an elevator utilizing thereof, are presented. The arrangement includes a corresponding number of phase legs and input connectors relative to a number of the plurality of motor windings, wherein each one of the input connectors is coupled to a respective one of the phase legs. At least some of the phase legs comprise at least two semiconductor devices. Second terminals of the phase legs are connected to each other, wherein the arrangement includes a number of semiconductor switches configured for forming a short-circuit between each of the plurality of motor windings.

Abstract: A method for performing a software update of a people conveyor component in a conveyor system includes downloading a software update from a remote update system based on a request from one or more of the remote update system, at least one conveyor component or the conveyor system such that the software update is downloaded as a background download without affecting an operation of the conveyor system.

Abstract: A drive system for driving an electric motor includes a drive control unit and a frequency converter including a speed controller. The drive control unit is configured to: define a speed reference of the electric motor; preset operating parameters of the speed controller to provide a first response time of the speed controller, before a drive of the electric motor is initiated; adjust at least one operating parameter of the speed controller to provide a second response time of the speed controller, after the speed of the electric motor reaches a constant speed, wherein the second response time is slower than the first response time; and readjust the at least one operating parameter of the speed controller to provide the first response time, before a deceleration from the constant speed is initiated. A method is disclosed for controlling the drive system for driving the electric motor.

Abstract: An electrical converter unit and a method for reducing thermal stress of a power semiconductor switch, such as an IGBT, of an electrical converter unit, the electrical converter unit comprising at least a gate control circuit wherein the electrical converter unit controls an electrical motor. The method comprises determining load and estimating required motor current based on the determined load and/or a predetermined speed profile. The electrical converter unit has at least a first operating state and a second operating state. The second operating state is used if predetermined criteria is fulfilled, the predetermined criteria relating to at least one of the following: estimated required current, measured motor speed, temperature of the power semiconductor switch and/or electrical converter unit, temperature model of the power semiconductor switch and/or electrical converter unit.

Abstract: A method for determining a rotor position of an electric motor, an elevator and an electrical converter unit are presented. The method comprises supplying a first excitation signal to the electric motor, determining a first response signal generated in the motor in response to the first excitation signal, determining, based on the first response signal, an electrical angle of a direct axis of the motor with respect to a stationary reference frame, supplying a second excitation signal to the motor, wherein the second excitation signal is based on the determined electrical angle, determining a second response signal generated in the motor in response to the second excitation signal, and determining the rotor position based on the second response signal.

Abstract: A people conveyor system and a method for software update of a people conveyor component in a people conveyor system, such as an elevator system, an escalator system and/or a moving walkway system. The conveyor system comprises a plurality of conveyor components, each said conveyor component comprising a memory and a processor running an application software, an updating means for updating conveyor component software, the updating means being communicatively connected to the conveyor components, wherein the updating means comprises or is connected to a processor and a memory, and at least one communication channel, arranged between the updating means and a remote update system.

Abstract: A people conveyor system and a method for software update of a people conveyor component in a people conveyor system, such as an elevator system, an escalator system and/or a moving walkway system. The conveyor system comprises a plurality of conveyor components, each said conveyor component comprising a memory and a processor running an application software, an updating means for updating conveyor component software, the updating means being communicatively connected to the conveyor components, wherein the updating means comprises or is connected to a processor and a memory, and at least one communication channel, arranged between the updating means and a remote update system.

Abstract: A safety system of an elevator provided herein may comprise a safety controller, a sensor unit configured to generate a first sensor signal indicating a travelling parameter and to provide the first sensor signal to an elevator drive unit of the elevator, and a signal converter connected to the sensor unit and configured to convert the first sensor signal into a second signal in a second format compatible with the safety controller and to provide the second signal in the second format to the safety controller. The safety controller may be configured to receive the second signal in the second format and to determine, based on the second signal, if there is an emergency condition.

Abstract: A method for identifying parameters, such as a magnetization-axis and torque-axis inductances, of a permanent magnet motor of an elevator includes applying, such as by a brake controller, at least one hoisting machinery brake to prevent rotation of a rotor of the permanent magnet motor, determining, by a first method, a mean value of motor inductance, as well as the magnetization-axis inductance and the torque-axis inductance as relative inductance values based on the mean value, determining, by a second method, being different than the first method, a mean value of motor main inductances, and determining absolute values of the magnetization-axis and the torque axis inductances based on the motor main inductance obtained by the second method and the relative inductance values obtained by the first method.

Abstract: A method for determining a rotor position of an electric motor, an elevator and an electrical converter unit are presented. The method comprises supplying a first excitation signal to the electric motor, determining a first response signal generated in the motor in response to the first excitation signal, determining, based on the first response signal, an electrical angle of a direct axis of the motor with respect to a stationary reference frame, supplying a second excitation signal to the motor, wherein the second excitation signal is based on the determined electrical angle, determining a second response signal generated in the motor in response to the second excitation signal, and determining the rotor position based on the second response signal.

Abstract: A method for dynamic braking of a permanent magnet motor, and an elevator utilizing thereof, are presented. The arrangement includes a corresponding number of phase legs and input connectors relative to a number of the plurality of motor windings, wherein each one of the input connectors is coupled to a respective one of the phase legs. At least some of the phase legs comprise at least two semiconductor devices. Second terminals of the phase legs are connected to each other, wherein the arrangement includes a number of semiconductor switches configured for forming a short-circuit between each of the plurality of motor windings.

Abstract: A method is disclosed for controlling single-phase DC/AC converters, along with a converter arrangement having at least two single-phase DC/AC converters. A controller is provided which can control the at least two single-phase DC/AC converters, and an isolation transformer, wherein outputs of the at least two single-phase DC/AC converters are cascade-connected with each other and an input of the isolation transformer. The controller is configured to control the at least two single-phase DC/AC converters to deliver power from their inputs to their outputs by turns.

Abstract: An inverter assembly having a DC circuit, inverter, and controller (CTRL) configured to control the inverter, the inverter being, for example, a multilevel inverter having a first half bridge (HB1) and a second half bridge (HB2). The controller (CTRL) can be adapted to provide a first operating state in which the controller (CTRL) operates the inverter as a full-bridge inverter. The controller (CTRL) is further adapted to provide at least one further operating state in which the controller (CTRL) operates the inverter as a half-bridge inverter, the controller (CTRL) being adapted to select an operating state based on predetermined conditions.

Abstract: A method of controlling the grid-side current of a single-phase grid-connected converter having an LCL filter connected between the output of the converter and the grid includes measuring a grid voltage and at least one signal in a group of signals consisting of a grid-side current, a converter-side current and a capacitor voltage, estimating the fundamental component of the grid voltage, forming a grid-side current reference, a converter-side current reference and a capacitor voltage reference for the grid-side current of the LCL filter, forming estimates for the non-measured signals in the group of signals, forming a grid-side current difference term, a converter-side current difference term and a capacitor voltage difference term, and controlling the output voltage of the converter based on the grid voltage, a formed injection term and a formed estimate of the harmonic distortion term to produce a grid side current corresponding to the current reference.

Abstract: Exemplary embodiments are directed to an inverter and a method for controlling an inverter. The inverter includes a DC link having two capacitor units in series and a neutral point between the capacitor units, and a first and a second inverter leg. Both inverter legs are connected between the poles of the DC link and include four switching devices connected in series. Both inverter legs include an upper connection point between the two topmost switching devices, a lower connection point between the two bottommost switching devices, and an output between the two middle switching devices. Both inverter legs further include a first rectifier device connected between the DC link neutral point and the leg upper connection point, and a second rectifier device connected between the DC link neutral point and the leg lower connection point.

Abstract: A method of controlling the grid-side current of a single-phase grid-connected converter having an LCL filter connected between the output of the converter and the grid. The method includes measuring a grid voltage (vS) and at least one signal in a group of signals consisting of a grid-side current (i0), a converter-side current (i1) and a capacitor voltage (vC0).

Abstract: A non-isolated DC-DC converter assembly includes a boost converter and a ?uk converter connected together in a specific way. The non-isolated DC-DC converter assembly allows for grounding of a source and load at the same time, and provides a complete adjustability of the output voltage of the non-isolated DC-DC converter.