摘要:
A service controller for crowded elevator cars includes an illuminating apparatus (4) furnished in a top part of a car (1) that is configured to illuminate the car (1) interior, at least one elongated light sensor unit (8) constituted by multiple light sensors (10) on a base member (9) and installed along corner regions (7a, 7b) formed between a vertical wall surface (5) of the car and the car's floor surface (6), and a judgment device (11) that is configured to determine whether there is passenger boarding space in the car (1) based on the output of the light sensors (10).
摘要:
A controller for controlling a reactive series compensator serially inserted at compensator terminals into a power transmission line for controlling the line current. The controller includes a current control loop and a voltage control loop. A current controller outputs a control voltage (ccout) indicating a desired compensator terminal output voltage (uc). A control method selector means generates, in a low output voltage region, a constant reference voltage (uDCref) for the voltage control loop and a variable modulation index mq of a modulation signal m=md cos (&ohgr;t) −mq sin (&ohgr;t). In a high output voltage range, the control method selector outputs a constant modulation index mq and a variable reference voltage (uDCref). The voltage controller outputs the modulation index md of the modulation signal m. Furthermore, the control method selector can include a rate limiter for limiting the change rate of the reference voltage (uDCref). In connection with the control method selection and/or the rate limiter, a decoupling control for making the voltage and current control loops independent from each other can be used. The controllers find particular application in transformerless reactive series compensators for single-phase or three-phase control.
摘要:
A power conversion apparatus has a voltage type power convertor, a power control circuit for outputting a first active power reference signal for the voltage type power convertor based on a power reference value Pref and a detection value P of a power detector, a DC voltage detector for outputting a second active power reference signal for the voltage type power convertor based on a DC voltage reference value Vdref and a detection value Vd of the DC voltage detector, and a gate control circuit for firing switching elements in the voltage type power convertor based on both first and second active power reference signals.
摘要:
An apparatus for detecting the amplitude and phase of an a.c. signal. The apparatus includes a signal detection circuit for detecting the a.c. signal, a signal splitting circuit for splitting the detected a.c. signal into first and second a.c. signals out of phase with each other by 90.degree.. The signal splitting circuit includes a low-pass filter, and a differentiation circuit. The apparatus also includes a phase compensation circuit coupled to the signal splitting circuit for receiving the first and second a.c. signals from the signal splitting circuit and for advancing the phase of an output signal of the apparatus by the phase lag of the low-pass filter. The phase compensation circuit also includes an amplitude and phased detection circuit for detecting the amplitude and phase of the detected a.c. signal by implementing a polar coordinate transformation of the first and second a.c. signals received from the signal splitting circuit.
摘要:
A suspended load swaying and vibration preventing apparatus for simultaneously controlling prevention of swaying of a suspended load and suppression of vibration of a structural body is provided in a container crane or the like. A trolley position and a trolley velocity are detected by a trolley position detector and a trolley detector. A swaying shift and a swaying velocity of the suspended load is detected by an image sensor. Furthermore, a shift and a velocity of a structural body is detected by a structural body vibration detector. A controller receives the detection signals from these sections, calculates the optimum trolley velocity based upon a control theory and outputs a trolley velocity command. Then, a trolley drive device is driven in accordance with the trolley velocity command from the controller. The suspended load is delivered to a desired position in a stable manner under the condition that swaying of the suspended load and the vibration of the structural body are suppressed.
摘要:
A power converting apparatus is configured with single-phase sub-converters (4) connected to AC input lines of individual phases of a three-phase main converter (3) in series therewith. In a control device (12) for performing output control of the power converting apparatus, a current command value calculating circuit (20) which adjusts a DC voltage command given to the main converter (3) so that DC voltages of the sub-converters (4) follow a command and generates AC current commands so that a DC voltage of the main converter (3) follows the DC voltage command is configured with a CPU, and AC currents are controlled by switching output voltage levels of the sub-converters (4) at an AC side thereof so that deviations of instantaneous AC current values from the AC current commands become smaller.
摘要:
A power converter includes a steady-state controller for outputting a first voltage command such that a detected power value matches a power command, a transient controller for outputting a second voltage command such that a voltage detected before the occurrence of a fault is maintained when the fault occurs, and a voltage command selector for switching the voltage command in such a way that the first voltage command is output when no power fault is detected and the sum of the first and second voltage commands is output when any power fault is detected.
摘要:
A reactive power compensator continues operation even when a higher harmonic wave component of an alternating-current power system increases. For an alternating current electric amount indicating one of an alternating voltage and an alternating electric current in an alternating-current power system, the reactive power compensator outputs a changing amount showing a change of the alternating current electric amount. An electric current command limits an electric current command signal based on the changing amount. For example, the changing amount is changed in accordance with the higher harmonic wave component included in the alternating current electric amount.
摘要:
A reactive power compensator continues operation even when a higher harmonic wave component of an alternating-current power system increases. For an alternating current electric amount indicating one of an alternating voltage and an alternating electric current in an alternating-current power system, the reactive power compensator outputs a changing amount showing a change of the alternating current electric amount. An electric current command limits an electric current command signal based on the changing amount. For example, the changing amount is changed in accordance with the higher harmonic wave component included in the alternating current electric amount.
摘要:
An apparatus for detecting the amplitude and phase of an a.c. signal detects the a.c. signal with signal detection means (4), calculates an a.c. signal that is phase-shifted by the amount of the phase characteristic .phi. of the calculation circuit (14) at the frequency of the detected a.c. signal, multiplies the detected a.c. signal by cos .phi., and multiplies by 1/sin .phi. the multiplication result subtracted by the phase-shifted a.c. signal.