Patent application number | Description | Published |
20090300090 | APPARATUS AND METHOD FOR DETERMINING RESOLVER ANGLE - The invention concerns a method and apparatus ( | 12-03-2009 |
20090322273 | METHOD AND APPARATUS FOR CONTROLLING A MOTOR - The invention concerns a method and an apparatus for controlling a three-or-more-phase motor driven by a frequency converter. In the method, a change-over switch of the frequency converter is controlled to a continuously conducting state and at the same time the phase voltages or phase currents of the other phases are controlled by switching the change-over switches in those motor phases at a switching frequency substantially higher than the frequency of the fundamental wave of the phase voltage or phase current. The apparatus comprises in conjunction with the frequency converter a number of change-over switches, at least one change-over switch for each motor phase. The change-over switches comprise controllable change-over contacts. The apparatus further comprises in conjunction with the frequency converter means for determining the motor phase currents and means for controlling the change-over contacts. | 12-31-2009 |
20100187046 | RESTRICTION OF OUTPUT OF ELECTRICAL DRIVE AND PROTECTION OF AN ELEVATOR - The invention discloses a method for restricting the output of an electrical drive, and also a protection of an elevator. The electrical drive comprises a motor as well as a power supply appliance of the motor. In the method for restricting the output of an electrical drive the stator voltage vector is restricted to its limit value restricting only the component of the stator voltage in the direction of the q axis. In the protection of an elevator, the elevator comprises a machinery brake, a safety brake of the elevator car, and also an electrical drive. The protection of an elevator comprises a determination of at least one limit value, a restriction of the output of the electrical drive on the basis of at least one determined limit value, and also a restriction of the movement of the elevator car on the basis of at least one determined limit value. | 07-29-2010 |
20100300815 | MOVEMENT CONTROL OF AN ELEVATOR SYSTEM - A determination of the loading state of an elevator system and also a method for determining the loading state of an elevator system is described. The elevator system includes an elevator car and also a motor drive for moving the elevator car. The loading state of the elevator system is determined on the basis of the position deviation of the elevator motor that occurs during the determination of the loading state. | 12-02-2010 |
20110037421 | DETERMINATION OF THE POSITION OF THE ROTOR OF AN ELECTRIC MACHINE - The invention relates to a frequency converter, and also to a method for determining the position of the rotor of an electric machine. The frequency converter comprises a load bridge and also a control of the load bridge, for supplying electricity between the load bridge and an electric machine connected to the load bridge. The frequency converter comprises a determination for at least one electrical parameter of the aforementioned electric machine, and the frequency converter comprises a determination for the position of the rotor of the aforementioned electric machine. The load bridge is fitted to supply a first alternating electricity excitation signal, which is formed in relation to the electrical angle of the electric machine, to the aforementioned electric machine. The frequency converter is further fitted to determine the first alternating electricity response signal corresponding to the aforementioned first alternating electricity excitation signal, and the position of the rotor is determined on the basis of the first alternating electricity response signal. | 02-17-2011 |
20110108369 | DETERMINATION OF THE MOVEMENT OF A SYNCHRONOUS MACHINE - The invention relates to a method and an apparatus for determining the movement of a synchronous machine. The apparatus for determining the movement of a synchronous machine comprises a determination for at least one electrical magnitude of the synchronous machine; a determination of the position error of the rotor of the synchronous machine, which is fitted to determine the position error of the rotor on the basis of the aforementioned at least one electrical magnitude of the synchronous machine; and also a correction of the movement signal of the incremental sensor, which is fitted to correct the read movement signal of the incremental sensor on the basis of the aforementioned determination of the position error of the rotor of the synchronous machine. | 05-12-2011 |
20110198167 | ARRANGEMENT AND METHOD FOR SUPERVISING THE OPERATION OF A BRAKE - An arrangement and a method for supervising the operation of a brake includes a controllable electromechanical brake, including a magnetic circuit with at least two ferromagnetic parts fitted to move in relation to each other. A thrusting force is exerted between the ferromagnetic parts via a spring. The brake includes a magnetizing coil fitted into the magnetic circuit, for forming magnetic attraction between the parts of the brake. The arrangement includes a control of the brake, which includes at least one controllable switch, for adjusting the electricity supply of the magnetizing coil. The control of the brake comprises a supervision of the movement of the magnetic circuit of the brake. | 08-18-2011 |
20110290593 | TRANSPORTATION SYSTEM - A transportation system and a method are provided for backing up the operational state of a transportation system. The transportation system includes a control apparatus for controlling the operation of the transportation system. The control apparatus further includes capacitive energy storage and a power supply backup circuit adapted to maintain power supply from the said energy storage to a storage circuit for a given length of time in connection with an operational anomaly in power supply to the control apparatus. | 12-01-2011 |
20120286713 | DETERMINATION OF THE POSITION OF THE ROTOR OF AN ELECTRIC MACHINE - A frequency converter and a method for determining the position of the rotor of an electric machine are provided. The frequency converter includes a load bridge and a control of the load bridge, for supplying electricity between the load bridge and an electric machine connected to the load bridge. The frequency converter includes a determination for at least one electrical parameter of the electric machine, and includes a determination for the position of the rotor of the electric machine. The load bridge is fitted to supply a first alternating electricity excitation signal, which is formed in relation to the electrical angle of the electric machine, to the electric machine. The frequency converter is further fitted to determine the first alternating electricity response signal corresponding to the first alternating electricity excitation signal, and the position of the rotor is determined on the basis of the first alternating electricity response signal. | 11-15-2012 |