Patent application number | Description | Published |
20090237015 | Motor Control Device - To prevent a step-out of a permanent magnet synchronous type motor ( | 09-24-2009 |
20100045218 | Motor Control Device - To estimate an initial magnetic pole position in a short time, estimated axes for control that correspond to the d-axis and the q-axis are set as the γ-axis and the d-axis, and a high frequency rotation voltage or alternating voltage on the γδ coordinate system is applied to the motor. A high frequency current i | 02-25-2010 |
20100060211 | Inverter Control Apparatus And Motor Drive System - An inverter control apparatus that controls a three-phase inverter which transforms a direct-current voltage into an alternating three-phase voltage, the inverter control apparatus includes: a voltage command vector generation portion that generates a first voltage command vector for specifying a vector of a voltage to be applied to a three-phase load that is connected to the inverter; a voltage command vector correction portion that in performing overmodulation with the inverter, corrects the first voltage command vector by setting a limit onto a coordinate-axis component of the first voltage command vector on an ab coordinate system to generate a second voltage command vector, wherein the inverter is so controlled that a voltage depending on the second voltage command vector is applied to the load, and the ab coordinate system is a coordinated system that depending on a phase of the first voltage command vector with respect to a predetermined fixed axis on a two-dimensional fixed coordinate system, rotates in stepwise fashion for every 60 degrees in electrical angle with respect to the fixed coordinate system. | 03-11-2010 |
20100072929 | Motor Control Device - A motor control device that includes a first speed estimator estimating the rotation speed of the rotor of a permanent-magnet synchronous motor and that controls the motor so that a first estimated rotation speed estimated by the first speed estimator follows the specified speed value further includes a second speed estimator that estimates the rotation speed of the rotor by an estimation method different from that used by the first speed estimator. The motor control device detects synchronization failure based on a comparison between a second estimated rotation speed estimated by the second speed estimator and the first estimated rotation speed or the specified speed value. | 03-25-2010 |
20110012461 | Permanent Magnet Synchronization Motor | 01-20-2011 |
20150068208 | AIR COOLING UNIT - An air cooling unit is an air cooling unit used in a Rankine cycle system and includes an expander and a condenser. The expander recovers energy from a working fluid by expanding the working fluid. The condenser cools the working fluid using air. The air cooling unit includes a heat-transfer reducer that reduces heat transfer between the expander and an air path. | 03-12-2015 |
20150084346 | POWER GENERATION CONTROL SYSTEM, POWER GENERATION APPARATUS, AND CONTROL METHOD FOR RANKINE CYCLE SYSTEM - A power generation control system includes a converter and a controller. The converter controls a generator of a Rankine cycle system, the Rankine cycle system including an expander, the generator, which is interconnected to the expander, a pump which feeds a working fluid, and an evaporator which evaporates a working fluid. The controller causes the converter to execute, in at least one of a startup operation and a shutdown operation of the Rankine cycle system, first control in at least one of a startup operation and a shutdown operation of the Rankine cycle system such that the expander is prevented from expanding a working fluid if the working fluid at an outlet of the evaporator contains a liquid component while the pump is operating. | 03-26-2015 |
Patent application number | Description | Published |
20080197799 | MOTOR CONTROL DEVICE - The motor control device includes a current detecting portion for detecting a phase current that flows in an armature winding of a stator of a three-phase motor based on current that flows between an inverter for driving the motor and a DC power supply. The motor control device performs a position sensorless vector control for the motor based on a control current that is obtained by a three-phase to two-phase conversion of the phase current based on an estimated rotor position of the motor. The motor control device farther includes a superposing portion for superposing a superposed voltage having a predetermined frequency on a drive voltage for driving the motor and an estimating portion for deriving the estimated rotor position based on the superposed current that is extracted from the control current and flows in the motor in accordance with the superposed voltage. A voltage vector locus of the superposed voltage from the superposing portion presents an ellipse. | 08-21-2008 |
20090021195 | MOTOR CONTROL DEVICE AND MOTOR DRIVE SYSTEM - Let an axis parallel to a magnetic flux produced by a permanent magnet provided on a rotor of a motor be called a d-axis, let an axis leading the d-axis by an electrical angle of 90 degrees be called a q-axis, and let control axes corresponding to the d-axis and the q-axis be called a γ-axis and a δ-axis, respectively. Then, a motor control device performs vector control of the motor with the γ-axis and the δ-axis made different from the d-axis and the q-axis, respectively, and with a motor current passing through the motor broken down into a γ-axis current on the γ-axis and a δ-axis current on the δ-axis. The motor control device has an estimator that estimates, as an estimated magnetic flux, a flux linkage of an armature winding of the motor, or estimates, as an estimated induction voltage, an induction voltage generated by the flux linkage and the rotation of the motor; and a specified current value deriving portion that derives, by using the estimated magnetic flux or the estimated induction voltage, a specified γ-axis current value to be followed by the γ-axis current. | 01-22-2009 |
20090026988 | Motor Control Device - A motor control device includes a motor current detector for detecting motor current flowing in a three-phase motor based on current flowing between an inverter driving the motor and a DC power supply, a specified voltage vector generating portion for generating a specified voltage vector indicating a voltage vector to which an applied voltage to the motor should follow based on a magnetic flux linkage of an armature winding of the motor, a specified voltage vector correcting portion for correcting the generated specified voltage vector, and a magnetic flux estimating portion for estimating the magnetic flux linkage based on the motor current and the specified voltage vector after the correction. The motor control device controls the motor via the inverter in accordance with the specified voltage vector after the correction. | 01-29-2009 |
20090267550 | Motor Control Device And Generator Control Device - To estimate a fluctuation component of the torque generated at the motor accurately, a motor control device ( | 10-29-2009 |
20110133678 | MOTOR CONTROL DEVICE, MOTOR DRIVE SYSTEM AND INVERTER CONTROL DEVICE - An inverter control device includes a phase current detection unit which is connected to a current sensor. The current sensor detects current flowing between a three-phase inverter which converts a DC voltage into AC three-phase voltages and a DC power supply which outputs the DC voltage, and the phase current detection unit detects phase current flowing in each phase of the inverter from a result of detection by the current sensor, so as to control the inverter on the basis of a result of detection by the phase current detection unit. The phase current detection unit includes an estimation block which estimates phase current of an intermediate voltage phase or current corresponding to the phase current of the intermediate voltage phase as a first estimated current, and estimates phase current of a maximum voltage phase or phase current of a minimum voltage phase using the first estimated current so that each phase current can be detected. | 06-09-2011 |
20110309781 | Motor Control Device And Motor Drive System - Provided is a motor control device including a voltage specifying unit which generates a specified voltage signal indicating a target value of an applied voltage to a motor on the basis of a specified current signal indicating a target value of supplied current to the motor, so as to control the motor in accordance with the specified voltage signal. An update unit is further provided, which sequentially updates a specified field current signal that is a field current component of the specified current signal to be given to the voltage specifying unit on the basis of difference information between a value of the specified voltage signal and a limit voltage value defined as an upper limit value of the applied voltage. The update unit includes a low pass filter. The specified field current signal after the update is generated on the basis of a signal obtained by passing the specified field current signal before the update through the low pass filter and the difference information. Otherwise, the specified field current signal after the update is generated on the basis of a signal obtained by passing an intermediate signal derived from the specified field current signal before the update and the difference information through the low pass filter. | 12-22-2011 |