Abstract: In a controlling device for a permanent magnet synchronous motor, an asynchronous pulse mode is switched to a synchronous pulse mode in a situation where a modulation factor has become equal to or larger than a first set value or in a situation where an inverter output frequency has become equal to or higher than a second set value. The synchronous pulse mode is switched to the asynchronous pulse mode in a situation where the modulation factor has become smaller than the first set value, and also, the inverter output frequency has become lower than the second set value. By setting the second set value so that the number of pulses included in a half cycle of an output voltage fundamental wave of the inverter is equal to or larger than a predetermined value, it is possible to inhibit current oscillations and torque ripples from occurring in the motor.

Abstract: An electric railway system includes an electric car and an electric-power supply device that supplies electric power to the electric car. The electric-power supply device includes a power source, and an overhead conductor portion connected to the power source. The electric car includes: a power collector installed on a roof of the electric car, having a contact conductor portion contactable to the overhead conductor portion, and being capable of raising and lowering the contact conductor portion based on an instruction from outside; a switching unit connected to the power collector, opening and closing a main circuit; an electric-power conversion device connected to the switching unit, performing an electric power conversion; an electric-power storage device connected to the electric-power conversion device; an electric motor driven by the electric-power conversion device, driving the electric car; and a control unit controlling at least the switching unit.

Abstract: An object is to provide a driving controller for an AC motor that can prevent generation of an excessive voltage between lines of a motor and between contacts of a motor cut-off contactor and a continuous arc between contacts of the motor cut-off contactor, regardless of the type of a fault occurred, even when a phase in which a current zero point is not generated and a phase in which a current zero point is generated coexist in a fault current that flows between an inverter and the motor. A control unit is configured to open a motor cut-off contactor not at a time when a state of a detected current is determined to be abnormal but at a time when the state of the current is determined to be normal, even when a basic contactor-close command MKC0 becomes off (L level).

Abstract: A cooling device for cooling a plurality of switching elements included in each of a converter unit and an inverter unit includes a fin base that serves as a switching element attachment plane on which the switching elements are mounted and a plurality of fins arranged on a plane opposite to the switching element attachment plane. When an electric power converting circuit is a single- or multi-phase bridge circuit including a plurality of sets of legs each formed with a positive-side arm and a negative-side arm, the switching elements constituting the legs of different phases are arranged in a row on the fin base in a traveling direction of a railway electric car.

Abstract: Provided is a vector control device for a permanent magnet synchronous motor driven by an inverter. The vector control device includes: a current command generation unit for generating a d-axis current command id* and q-axis current command iq* from a given torque command T*; and a current control unit operating so that the motor current coincides with the current command. The current command generation unit includes: a d-axis basic current command generation unit for generating a first d-axis basic current command id1* by using the torque command; a limiter unit for inputting the current command id1* and outputting a value limited to below zero as a second d-axis basic current command id2*; a d-axis current command compensation unit for outputting the current command id2* corrected in accordance with the d-axis current command compensation value dV as a d-axis current command id*; and a q-axis current command generation unit for generating a q-axis current command iq* from the d-axis current command id*.

Abstract: A control apparatus of an alternating-current motor includes an inverter which is connected to a direct-current source and outputs three-phase alternating currents to the alternating-current motor, a current detector which detects a current of the alternating-current motor, a voltage command/PWM signal generation unit which calculates an output voltage command of the inverter based on a signal from the current detector and generates a pulse width modulation signal to control a switching element arranged in the inverter based on the output voltage command, and a motor current imbalance compensation unit which generates a motor current imbalance compensation amount based on the current detected by the current detector. The pulse width modulation signal is directly or indirectly adjusted at the voltage command/PWM signal generation unit based on the motor current imbalance compensation amount in accordance with a driving state of the inverter.

Abstract: A power conversion device includes: an inverter that drives an alternating-current motor by converting a direct-current voltage into an alternating-current voltage of an arbitrary frequency; an alternating current disconnecting switching unit connected between the inverter and the alternating-current motor; a current detector that detects an output current of the inverter; and a controller that performs on/off-control of the plural switching elements in the inverter and switching control with respect to the switching unit, based on at least a current detected by the current detector. The controller has a configuration to be able to interrupt a fault current by setting the fault current to a state of generating a current zero point, when the fault current containing a direct-current component is generated between the inverter and the alternating-current motor.

Abstract: To propose a control apparatus for an electric train, in which the regenerative energy of a DC power feed circuit can be consumed without disposing the brake chopper or electric-double-layer capacitor of the DC power feed circuit. A control apparatus for an electric train according to this invention includes an AC electric motor which drives the electric train, and a variable-voltage variable-frequency inverter which controls the AC electric motor, and further includes an auxiliary power source device connected to a DC power feed circuit, and load control means for controlling a load connected to the auxiliary power source device, wherein the load control means receives an inverter state signal representative of an operation state of the variable-voltage variable-frequency inverter from the it, and the load control means controls the load in accordance with the inverter state signal.

Abstract: There is provided a vector control device for an alternating-current electric motor having a damping controller which automatically calculates an optimum damping operation amount and does not require any gain setting itself, whereby an adjustment work of a control system can be simplified. The vector control device is equipped with a vector controller 30 for executing vector control on the alternating-current electric motor 6 in accordance with a current command or a torque command, and a damping controller 40 for calculating a damping operation amount for suppressing variation of a capacitor voltage Efc.

Abstract: A power storage system regulates DC power from a DC power supply into prescribed voltage and current using a DC-DC converter unit for storage in a storage unit. On the DC power supply side of the DC-DC converter, the system includes a primary side current detecting unit, a primary side voltage detecting unit, a primary side switch unit, and a primary side filter unit. On the storage unit side of the DC-DC converter, the system includes a secondary side filter unit, a secondary side switch unit, a secondary side voltage detecting unit, and a secondary side current detecting unit. The on/off states of the primary and secondary side switch units, and the DC-DC converter unit are controlled by a system control unit provided with an externally applied operation command and signals obtained from elements such as the primary side current detecting unit and the primary side voltage detecting unit.

Abstract: A wheel diameter measuring apparatus for measuring a wheel diameter of an electric vehicle of speed sensorless vector control to which a synchronous motor is applied is obtained. A wheel diameter measuring apparatus of an electric vehicle comprising a synchronous motor driven by an electric power converter for converting a DC voltage into an AC voltage comprises a voltage detector for detecting an AC voltage generated by a magnetic field of the synchronous motor during coasting of the electric vehicle in which the electric power converter stops, and a calculation part for calculating a wheel diameter of a wheel driven by the synchronous motor from an AC voltage detected by the voltage detector and speed information about the electric vehicle.

Abstract: Provided is a controlling device for a railway electric car, the controlling device being able to detect a slipping/sliding phenomenon during, in particular, high-speed travel and to exercise slipping/sliding control in an appropriate manner. A slip controlling unit 1 includes a first adhesion level index generating unit and a second adhesion level index generating unit. In a normal slipping state in which an acceleration changes instantaneously, torque control is exercised by using a first adhesion level index generated by the first adhesion level index generating unit based on an acceleration deviation and a speed deviation. In a slipping state during high-speed travel, because the acceleration deviation and the speed deviation are small, torque control is exercised by using a second adhesion level index generated by multiplying the first adhesion level index by a gain equal to or smaller than 1 generated by the second adhesion level index generating unit.

Abstract: A motor controlling apparatus having a controller for controlling a plurality of inverters correspondingly provided to each of a plurality of alternating-current motors is reduced in size, mass, and cost by effectively grouping operations performed by each calculation unit included in the controller. This controller for controlling the inverters includes: a first common calculation unit and a second common calculation unit that calculate and output control signals that are common to each of the inverters; individual calculation units that individually calculate and output a control signal related to each of the inverters; and a common logic calculation unit 60 that outputs a gate signal for controlling switching of each of the inverters based on the signals received from the first common calculation unit, the second common calculation unit, and the individual calculation units.

Abstract: In a control apparatus for an electric vehicle there are provided a first inverter that drives a motor; a second inverter that supplies electric power to a load; a power storage unit that supplies electric power to the first and second inverters; and a load control unit that can control a load amount, in accordance with a power storage amount in the power storage unit, or a condition amount thereof. The load control unit can perform control of an air blower, an air conditioner, and a ventilator, for example, stopping part or all of them.

Abstract: [Problem] To propose a control apparatus for an electric train, in which the regenerative energy of a DC power feed circuit can be consumed without disposing the brake chopper or electric-double-layer capacitor of the DC power feed circuit. [Means] A control apparatus for an electric train according to this invention includes an AC electric motor which drives the electric train, and a variable-voltage variable-frequency inverter which controls the AC electric motor, and further includes an auxiliary power source device connected to a DC power feed circuit, and load control means for controlling a load connected to the auxiliary power source device, wherein the load control means receives an inverter state signal representative of an operation state of the variable-voltage variable-frequency inverter from the it, and the load control means controls the load in accordance with the inverter state signal.

Abstract: A power converter includes: a converter (1) which rectifies an AC power; capacitor series assemblies (2A, 2B) connected to the DC side of the converter; an inverter (3) which assumes that one end of the capacitor series assemblies is at a high potential, the other end is at a low potential, and a series connection point is at an intermediate potential and selects one of the high potential, the intermediate potential, and the low potential for output of a 3-phase AC; an inverter control unit (4) which controls the inverter (3); and a voltage measuring device (8) which measures a capacitor voltage Vdc as a voltage between the both ends of the capacitor series assemblies (2A, 2B). The inverter control unit (4) has a beatless control unit (21) which controls the modulation ratio ? in accordance with a capacitor voltage Vdc and a frequency fixation unit (22) which fixes the frequency of the AC voltage outputted by the inverter (3) to an instruction value.

Abstract: According to the present invention, a bidirectional buck boost DC-DC converter can be obtained, in which power can flow bidirectionally from a primary side to a secondary side and from the secondary side to the primary side, regardless of a magnitude relation between a secondary-side voltage and a primary-side voltage in a state where different DC voltage sources are connected to the primary side and the secondary side in the DC-DC converter. A direction and a magnitude of the power can be automatically controlled to a desired value continuously on instantaneous value basis.

Abstract: The vector control device includes: secondary magnetic flux command computing means (40) for computing a secondary magnetic flux command to an induction motor (6) by taking a maximum voltage that an inverter (4) can generate into account on a basis of a torque command from an external, a DC voltage to be inputted into the inverter, and an inverter angular frequency, which is an angular frequency of an AC voltage to be outputted from the inverter; q-axis/d-axis current command generating means (8 and 9) for generating a q-axis current command and a d-axis current command on a d-q axes rotating coordinate system in reference to a secondary magnetic flux of the induction motor (6) on a basis of the torque command and the secondary magnetic flux command; output voltage computing means (voltage non-interference computation portion 14, adder 17, and adder 18) for computing an output voltage that the inverter (4) is to output on a basis of the q-axis current command, the d-axis current command, and a circuit constan

Abstract: Specific anomalies and details of failures as well as measures thereagainst are described that might possibly occur in electric power converters that drive and control permanent-magnet synchronous motors. An electric power converter capable of stable operation has a protective function of taking proper measures against such failures that might possibly occur.

Abstract: In a power converter a controller determines that an AC motor is in an abnormal state when a voltage of each phase of the AC motor detected by a voltage detector is in an unbalanced state where the voltage exceeds a predetermined value, and turns an opening/closing unit OFF to prevent damage generated in the AC motor from becoming worse. Moreover, the controller determines abnormality of the opening/closing unit based on a current of each phase detected by a current detector, and the controller performs control to reduce the number of revolutions of the AC motor upon determining that at least one of the AC motor and the opening/closing unit is in an abnormal state.