Sanyo Electric Co., Ltd.

Panasonic Intellectual Property Management Co., Ltd.

Panasonic Corporation

Advanced Software Technology & Mechatronics Research Institute of Kyoto

Iii Holdings 1, LLC

Yoshio Tomigashi

Takumi Hikichi

Atsuo Okaichi

Osao Kido

Noriyoshi Nishiyama

Masaaki Konoto

Osamu Kosuda

Tetsuya Matsuyama

Subaru Matsumoto

Akira Sakaguchi

Eiichiro Hashimoto

Hajime Hida

Michio Kunimitsu

Masahiko Hashimoto

Yoshitoshi Morita

Hiroshi Takao

Mamoru Kubo

Masaki Harada

Hideaki Aoki

Kazushige Kakutani

Keiji Kishimoto

Kenji Nojima

Kenji Ueyama

Kazuhisa Otagaki

Hideo Kawakami

Akira Okonogi

Shinya Yamamoto

Akihiro Hirao

Tomomi Yamaguchi

Tetsuya Mutsuyama

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.

Air cooling unit

Specific operation is executable in a Rankine-cycle power-generating apparatus. In the Rankine-cycle power-generating apparatus, a) in the specific operation, the control device adjusts the degree of opening of the opening/closing device so that the direct-current electric power absorbed by the electric power absorber approaches first electric power, or b) in the specific operation, the degree of opening of the opening/closing device is increased to the predetermined intermediate degree of opening so that the direct-current electric power absorbed by the electric power absorber falls within a predetermined range.

Rankine-cycle power-generating apparatus

A combined heat and power system according the present disclosure includes a Rankine cycle apparatus including an evaporator that heats a working fluid by heat exchange between the working fluid and a heat source medium, an expansion machine that converts expansion power of the working fluid into rotational power, and a condenser that cools the working fluid by heat exchange between the working fluid and a heat medium, and a thermal circuit for using the heat medium heated by the condenser. An expansion volume ratio of the expansion machine is equal to or less than an expansion ratio in a theoretical Rankine cycle determined based on a state of a temperature and a pressure of the working fluid at a discharge port of the expansion machine and a state of a temperature and a pressure of the working fluid at a suction port of the expansion machine.

Combined heat and power system including expander having expansion volume ratio equal to or less than that of theoretical rankine cycle

A thermal power generation apparatus includes a control circuit that selects a single operation mode from among a plurality of modes including a normal mode and a specific mode on the basis of a voltage in a commercial system. The normal mode is an operation mode in which alternating-current power output from an inverter is adjusted so that a direct-current voltage in a direct-current power line follows a target voltage. The specific mode is an operation mode in which direct-current power absorbed by an electric power absorber and/or the amount of heat per unit time supplied to a heat engine are/is adjusted so that the direct-current voltage follows the target voltage.

Thermal power generation apparatus and thermal power generation system

A liquid pump includes: a casing; a feed pipe bringing liquid from outside the casing to inside the casing; a pump mechanism provided in the casing and including a suction hole for sucking in the liquid and a discharge hole for discharging the liquid sucked in via the suction hole; a suction space positioned in the casing on a suction-hole inlet side and making a flow path formed by the feed pipe and the suction hole communicate with each other; and a discharge space positioned on a discharge-hole outlet side in the casing and communicating with the discharge hole. The suction space includes a gas accumulation area that is positioned above a center of an opening at casing-side end of the feed pipe, when viewed vertically and that accumulates gas brought into the casing through the feed pipe together with the liquid to separate the gas from the liquid.

Liquid pump including a gas accumulation area and rankine cycle device including a liquid pump

A permanent magnet synchronous machine includes a rotor including a core body and an overhang protruding further in an axial direction than a core of a stator. An end surface of the core body includes an N-region disposed on a north pole and an S-region disposed on a south pole. The overhang includes first permanent magnets arranged along an outer edge of the end surface with distances therebetween and a plurality of second permanent magnets disposed on the end surface and adjacent to the first permanent magnets. The first permanent magnets include at least one of a permanent magnet comprising a north pole facing the N-region and a permanent magnet comprising a south pole facing the S-region. The second permanent magnets are provided in the configuration which causes the second permanent magnets to generate a magnetic flux extending from the S-region toward the N-region.

Permanent magnet synchronous machine

A Rankine cycle device in the present disclosure includes an evaporator as a heater, an expander, a cooler, a first temperature sensor, a second temperature sensor, and a control device. The first temperature sensor detects a temperature of the working fluid flowing from an outlet of the heater to an inlet of the expander in the circuit of the working fluid. The second temperature sensor detects a temperature of the working fluid flowing from an outlet of the expander to an inlet of the cooler. The controller controls a number of rotation of the expander based on a difference between a detected temperature of the first temperature sensor and a detected temperature of the second temperature sensor.

Rankine cycle device

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.

Power generation control system, power generation apparatus, and control method for rankine cycle 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.

Motor control device and motor drive system

To prevent a step-out of a permanent magnet synchronous type motor (), a motor control device () is provided to include a flux control unit () for deriving an excitation current command value (i&#x3b3;*) according to the rotation speed (&#x3c9;) of the motor, and a voltage shortage determination unit () for determining whether or not the supply voltage to the motor is running short based on the excitation current command value (i&#x3b3;*). When a negative excitation current command value (i&#x3b3;*) is smaller than a negative determination threshold value, the motor control device determines that the supply voltage is running short and prohibits an increase of the rotation speed or decreases the rotation speed.

Motor control device

To estimate a fluctuation component of the torque generated at the motor accurately, a motor control device () which controls a motor with a stator having armature winding and a rotor having a permanent magnet is provided to include a torque fluctuation component estimation unit for estimating a torque fluctuation component generated at the motor based on flux-linkage of the armature winding and an armature current that flows the armature winding. The torque fluctuation component estimation unit estimates the torque fluctuation component (T) based on an inner product (F&#xb7;i+F&#xb7;i) of a flux-linkage vector which is a vectorial representation of the flux-linkage and a current vector which is a vectorial representation of the armature current.

Motor control device and generator control device

To estimate an initial magnetic pole position, estimated control axes corresponding to the d-axis and q-axis are set as the &#x3b3;-axis and &#x3b4;-axis, and a with high frequency rotation voltage or alternating voltage on the &#x3b3;&#x3b4; coordinate system applied to the motor. A high frequency current iflowing in the motor is then extracted from a detected motor current (armature current) and a direct current component (i&#x3b3;&#xd7;i&#x3b4;)of a product of the &#x3b3;-axis and &#x3b4;-axis components of the high frequency current iis derived. Alternatively, the &#x3b3;'-axis component i&#x3b3; and the &#x3b4;&#x2032;-axis componentof the high frequency current ithat are shifted by &#x3c0;/4 in electric angle from the &#x3b3;-axis and the &#x3b4;-axis are used to obtain a direct current component of their product (i&#x3b3;&#xd7;i&#x3b4;). The magnetic pole position is then estimated by computing the axial error &#x394;&#x3b8; between the &#x3b3;-d axes utilizing the direct current components.

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.

Inverter control apparatus and motor drive system

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.

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Hirakata, Japan

Yoshio Tomigashi