摘要:
The present disclosure is a system for monitoring power that has a unified polyphase distribution transformer monitoring (PDTM) device that interfaces with at least three electrical conductors electrically connected to a transformer. In addition, the PDTM device measures a current and a voltage of each of the three electrical conductors. Additionally, the system has logic that calculates values indicative of power corresponding to the transformer based upon the currents and the voltages measured and transmit data indicative of the calculated values.
摘要:
A multiphase current sensing method wherein the sum of the phase currents is zero including: sensing a.c. and/or d.c. currents in first and second phases; sensing a.c. current in a predetermined a.c. frequency range in a third phase; and combining the current sensed in the first and third phases and the second and third phases and determining a gain correction factor to be applied to the currents sensed in the first and second phases.
摘要:
Provided is an apparatus (24) and method for determining a faulted phase resulting from a fault in a three-phase ungrounded power system (10). The method includes comparing a phase angle of an operating phasor to a phase angle of a fixed reference phasor The operating phasor is derived from a digitized signal sample of a plurality of measured signals of the power system(l?) The method also includes comparing a phase angle difference between the operating phasor and the fixed reference phasor to at least one threshold to determine the faulted phase. The fixed reference phasor may be a phase-to- phase voltage or a positive sequence voltage of the plurality of measured signals of the power system (10) The operating phasor may be a zero sequence current, a zero sequence voltage or a combination of a zero sequence current and a zero sequence voltage of the plurality of measured signals of the power system(l0).
摘要:
El dispositivo de control/protección para redes de distribución eléctrica consiste en un dispositivo numérico y trifásico, capaz de medir valores instantáneos de intensidad y de tensión de cada una de las fases y determinar las intensidades y tensiones homopolares, energías, potencias, etc., así como de desempeñar aplicaciones como seccionamiento automático de líneas en falta, control local, maniobras mediante telemando, automatismos, enclavamientos, etc., disponiendo a su vez, de una función de comunicaciones que junto con las entradas y salidas digitales que dispone el dispositivo, permite realizar el control y la supervisión de cada uno de los equipos eléctricos de la instalación tanto de forma local como remota.
摘要:
영상(zero phase) 성분을 검출하는 방법 및 장치가 제공된다. 영상(zero phase) 성분을 검출하는 장치는, 순차 샘플링 방식의 메터 칩(meter chip), 상기 메터 칩으로부터 복수의 상(phase)에 대한 순차 데이터를 취득하는 데이터 취득부 및 상기 취득된 순차 데이터로부터 상기 각 상(phase)별 순시 전류의 값을 합산하여 고장 검출용 순시 전류 값을 산출하고, 상기 산출된 고장 검출용 순시 전류 값을 이용하여 영상 전류 값을 산출하는 영상 전류 값 산출부를 포함한다.
摘要:
An apparatus and method are provided for monitoring and controlling a power system of an electrical submersible pump assembly. A sensor monitors an alternating current component of a downhole electrical imbalance voltage at a neutral point of a motor of the electrical submersible pump assembly. The sensor measurement is transmitted to a controller at the surface. The controller analyzes the alternating current component of the downhole electrical imbalance voltage and then adjusting an operation of the electrical submersible pump assembly, or scheduling maintenance, accordingly. Also, a model of a power system of an electrical submersible pump assembly is created to predict an alternating current component of a downhole electrical imbalance voltage. The model is modified as necessary responsive to measurements from the sensor. A controller adjusts surface currents according to the model of the power system to match downhole motor drive currents to thereby optimize the power system.
摘要:
Die Erfindung betrifft eine Vorrichtung (10) zur Erkennung einer Lastunsymmetrie in einem Drehstromnetz, wobei der gleichgerichtete zeitliche Verlauf eines dreiphasigen elektrischen Stromes durch eine dreiphasige Drehstromleitung (99) als eine dazu proportionale Eingangsspannungsinformation (35, 45) bereitgestellt ist, dadurch gekennzeichnet, dass die Eingangsspannungsinformation (35, 45) einem Maximalwertmodul (14, 24) zugeführt ist, dass durch das Maximalwertmodul (14, 24) eine erste Hilfsspannungsinformation (36, 46) bereitgestellt ist, welche einem näherungsweise konstant gehaltenen Spitzenwert der Eingangsspannungsinformation (35, 45) in einem vorgebbaren Zeitraum entspricht, dass die erste Hilfsspannungsinformation (36, 46) einem Proportionalmodul (15, 25) zugeführt ist, dass durch das Proportionalmodul (15, 25) eine zu der ersten Hilfsspannungsinformation (36, 46) proportionale zweite Hilfsspannungsinformation (37, 47) ausgegeben / bereitgestellt ist, dass die Eingangsspannungsinformation (35, 45) und die zweite Hilfsspannungsinformation (37, 47) jeweils einem Vergleichsmodul (16, 26) zugeführt sind, durch welches eine Angabe über die Lastunsymmetrie enthaltene Ausgangsspannungsinformation (38, 48) bereitgestellt ist.
摘要:
Provided is an apparatus and method for determining a faulted phase resulting from a fault in a three-phase ungrounded power system. The method includes comparing a phase angle of an operating phasor to a phase angle of a fixed reference phasor. The operating phasor is derived from a digitized signal sample of a plurality of measured signals of the power system. The method also includes comparing a phase angle difference between the operating phasor and the fixed reference phasor to at least one threshold to determine the faulted phase. The fixed reference phasor may be a phase-to- phase voltage or a positive sequence voltage of the plurality of measured signals of the power system. The operating phasor may be a zero sequence current, a zero sequence voltage or a combination of a zero sequence current and a zero sequence voltage of the plurality of measured signals of the power system.
摘要:
The invention relates to a method for compensating for a voltage unbalance in an electrical network, which is fed by using an apparatus based on controlling a flux linkage vector or a voltage vector. Concerning the apparatus based on controlling the flux linkage vector, the method comprises the steps of determining a flux linkage reference vector (ψref) comprising a positive sequence component (ψref,PSS) and a negative sequence component (ψref,NSS), and controlling the feeding apparatus of the network in such a manner that the flux linkage vector (ψ1) thereof follows the reference vector (ψref) with predetermined precision. The negative sequence component (ψref,NSS) of the flux linkage reference vector is arranged to compensate for the amplitude and phase unbalance of the voltage in the electrical network to be fed.