摘要:
An inverter controller comprising an AC motor as a load. A rectifying circuit converts AC power from an AC power source into DC power. A smoothing capacitor smoothens a DC voltage from the rectifying circuit. An inverter circuit converts DC power supplied via the smoothing capacitor into a desired frequency. A current detection circuit detects a output current of the inverter circuit. A voltage detection circuit detects a terminal voltage (Vpn) of the smoothing capacitor. A voltage command calculation circuit calculates a voltage command to the AC motor. A speed command calculation circuit calculates a speed command to be used when it is determined that the AC power source is in a power failure state or when the terminal voltage (Vpn) reaches a certain value.
摘要:
The present invention provides an inverter controller and a method for operating the inverter controller, enabling continuous operation without requiring difficult adjustments and without causing a trip or unnecessary torque ripple at overvoltage or undervoltage during an instantaneous power failure or during regenerative operation.An inverter controller (20) equipped with a voltage detection circuit (5) for detecting the terminal voltage of the smoothing capacitor (2) and a speed command selection circuit (6) for detecting an instantaneous power failure in an AC power source has a power calculation circuit (36) for calculating the power output thereof and a speed command calculation circuit (7) for calculating a power output target value and a speed command value during the instantaneous power failure.
摘要:
It is the objective of the present invention to provide a sensorless vector control method and a control apparatus, for an alternating-current motor, that can smoothly restart an alternating-current motor in the free running state.According to the present invention, when a current that flows in an alternating-current motor (2) at a restart time 7 the alternating-current motor (2) continuously flows at a designated current level or higher for a designated period of time, it is determined that the rotational direction or the velocity of the alternating-current motor (2) is incorrectly estimated, and a direct current or a direct-current voltage is again applied to again estimate the rotational direction and the velocity.
摘要:
It is the objective of the present invention to provide a sensorless vector control method and a control apparatus, for an alternating-current motor, that can smoothly restart an alternating-current motor in the free running state. According to the present invention, when a current that flows in an alternating-current motor (2) at a restart time 7 the alternating-current motor (2) continuously flows at a designated current level or higher for a designated period of time, it is determined that the rotational direction or the velocity of the alternating-current motor (2) is incorrectly estimated, and a direct current or a direct-current voltage is again applied to again estimate the rotational direction and the velocity.
摘要:
A control device includes a slip calculator that calculates a first slip frequency of an induction motor, a current detector that detects motor current that passes through the induction motor, an adder that calculates a primary frequency by adding a speed command and a second slip frequency that are given, a command voltage generation unit that generates first command voltage from the primary frequency, a voltage error observer unit that estimates a command voltage error from the first command voltage and the motor current, a slip correction unit that calculates a slip correction amount from the command voltage error, an adder that calculates the second slip frequency by adding the first slip frequency and the slip correction amount, and a voltage error correction unit that corrects the first command voltage using the command voltage error and outputs second command voltage.
摘要:
A simple and accurate dead time dispersion measurement method and a voltage source inverter control method that can prevent the occurrence of an unstable phenomenon are provided.The control method controls a voltage source inverter of a PWM system, which includes a power semiconductor device controlling a level of a voltage, a frequency and a phase. According to the control method, before operation, voltage error information for each polarity of respective phase currents of the inverter is stored. And during the operation, the voltage error information is read to compensate for a voltage instruction value or a pulse width of a PWM instruction signal, so that a voltage error can be corrected.
摘要:
An apparatus for opening and closing a door of a container apparatus of a vehicle can include a single knob, a shaft, a fixed member, a shaft biasing spring, an arm, and a cam. The shaft is movable in an axial direction of the shaft and rotatable about an axis of the shaft. The shaft has a radially extending portion. The shaft has first, second, and third rotational positions. The third rotational position is offset by 180 degrees from the first rotational position. The arm has an opening side arm corresponding to the first rotational position and a closing side arm corresponding to the third rotational position. A cam driving protrusion for rotating the cam is provided to at least one of the opening side arm and the closing side arm. A support member may be coupled to the arm. The support member includes an opening side support member and a closing side support member. Each of the opening side support member and the closing side support member has a recess formed therein for preventing the radially extending portion from interfering with the opening side support member or the closing side support member when the shaft rotates from the second rotational position to the third rotational position.
摘要:
In an image display device, how R, G, and B light is emitted to display an image on a display panel is measured with a sensor, and, according to the measurement value obtained from the sensor, the power with which to drive a light source that supplies light needed for the display operation of the display panel is varied so that the brightness or chromaticity of the display panel is corrected.
摘要:
5-Amino-7-((3S,4S)-3-amino-4-methyl (or ethyl)-1-pyrrolidinyl)-1-cyclopropyl-6-fluoro-1,4-dihydro-8-methyl-4-oxoquinoline-3-carboxylic acid or a pharmacologically acceptable salt thereof represented by the following formula wherein asymmetric carbon atoms marked with asterisks are in the S-configurations and R.sup.1 represents methyl group or ethyl group; and an antibacterial agent comprising said compound as an active ingredient. ##STR1##
摘要:
A 5-amino-8-methyl-7-pyrrolidinylquinoline-3-carboxylic acid derivative represented by the general formula: ##STR1## wherein R.sup.1 is a hydrogen atom or a lower alkyl group; R.sup.2 is a hydrogen atom, a lower alkyl group, a lower alkanoyl group, a halogenated lower alkanoyl group or a residue of carboxylic acid ester; R.sup.3 is a hydrogen atom or a lower alkyl group; R.sup.4, R.sup.5 or R.sup.6 are each independently a hydrogen atom or a lower alkyl group; or two of R.sup.4, R.sup.5 and R.sup.6 may be taken together to form a --(CH.sub.2).sub.n -group wherein n is 1 or 2, a stereoisomer thereof, or a pharmacologically acceptable salt thereof, the process for preparing these compounds, a pharmaceutical composition comprising an effective amount of these compounds and methods for the treatment of infectious diseases through the administration to patients of an effective amount of these compounds, and intermediates of these compounds are disclosed. These compounds are effective as antibacterial agents.