摘要:
System and methods for coordinating the control system of a switched power capacitor with an integrated resonance protection function. The coordination system coordinates the function of a switched power capacitor's primary control system and resonance protection system to avoid duplication of tasks and on/off operation deadlock. The coordination system adjusting calculations made by the primary control system in response to a determination of a harmonic resonance condition by the resonance protection system.
摘要:
An electrical power system includes a transmission line for transmitting electrical power, series capacitance compensation series-coupled to the transmission line adjacent one end thereof, where the series compensation includes a capacitance having a value (−j XCAP), and a protective relay at the one end of the transmission line for monitoring line voltages and line currents on the transmission line. Upon sensing a fault, an impedance Z of the line is calculated based on the monitored line voltages and line currents. The calculated impedance Z is adjusted according to the value of the capacitance of the series compensation (−j XCAP) to result in a modified impedance ZMOD, and the phasor angle Of ZMOD is examined to determine the direction of the sensed fault. The fault is in a first direction if the phasor angle is between X and X+180 degrees and is in a second direction opposite the first direction if the phasor angle is between X+180 and X+360 degrees.
摘要:
A reach-measurement method is used in connection with a series-compensated line of a power system. The series-compensated line includes an installed series capacitance having a bus side and a line side, and a non-linear protection device parallel to the installed series capacitance. The series-compensated line has a line current, a bus side voltage, and a line side voltage. The series capacitance and the non-linear protection device have a capacitance voltage thereacross equal to the bus side voltage minus the line side voltage. In the method, a number (n) of line current samples are measured, where such samples are representative of values of a line current waveform at successive instants of time on the series-compensated line. Capacitance voltage values are computed based on the measured line current samples in accordance with an equation which takes into account the non-linear protection device parallel to the installed series capacitance. A prescribed power system function is then performed based on the computed capacitance voltage values.
摘要:
A method and system for detecting the peak of respective half-cycles of a sinusoidal waveform. The sinusoidal waveform is rectified and only sample points above a first threshold are analyzed. The peaks of each half-cycle are only accepted if they are above a second, greater threshold. Peaks below the second threshold are not accepted. The peaks themselves are detected by starting a counter at the first sample in the rectified waveform which is above the first threshold value. Once the rectified waveform descends below the first threshold, the counter is stopped and the maximum value of the previous k samples is the peak value, where k is the counter value for the successive samples above the first threshold. The peak value so determined is rejected if it is less than the second threshold value. On the other hand, when the peak value is above the second threshold, it is averaged with the last valid peak value (above the second threshold). Thus, the V/Hz value remains the same until a new, valid peak is determined. A preferred embodiment implements such a digital peak detector in a digital relay system for detecting overexcitation of a power system.
摘要:
An accurate impedance measurement method for a power system transmission line is disclosed for improving various protection functions, i.e., distance protection and/or fault location estimation. The method is less sensitive to harmonics and other transient problems introduced to power systems by series capacitance and the like, and is easily incorporated into existing protective relays. In the method, a number (n) of current and voltage samples (Ik, Vk) representative of values of current and voltage waveforms are measured, respectively, at successive instants of time on a conductor in a power system. The number n is an integer greater than I and the index k takes on values of 1 to n. Resistance (R) and inductance (L) values are computed in accordance with an equation in which R and L are related to sums of differences in values of successive current and voltage samples. A prescribed power system function is then performed based on the computed R and L values.
摘要:
Provided is an image analyzing apparatus for efficiently performing detection of an object and tracking of a specified object, including a feature value recording section that records a plurality of reference feature values different in type from each other; a feature value extracting section that extracts a plurality of feature values different in type from each other, from each of a plurality of moving image constituent images included in a moving image; an object extracting section that extracts an object from the moving image constituent images, based on a degree of matching of the plurality of extracted feature values with respect to the plurality of reference feature values recorded in the feature value recording section; a reference feature value calculating section that calculates, from the plurality of reference feature values recorded in the feature value recording section, a plurality of reference feature values adjusted to the feature values of the extracted object, to a predetermined degree corresponding to the type; and a feature value updating section that updates the plurality of reference feature values recorded in the feature value recording section, with the plurality of reference feature values calculated by the reference feature value calculating section.
摘要:
Hanging type energy saving window film consists of a clear or tinted plastic film that hangs down from the wall to cover the window and serves to control the transfer of heat and light for energy saving purposes. Hanging type energy saving window film includes a film, a hanging system, a weight, and a sealing system. The hanging type energy saving window film covers the entire window on the inside of a room to insulate and control light and heat transfer. A clear window film allows light to enter the room and also reduces the amount of heat that escapes through the window pane during winter. A colored window film blocks sunlight and insulates the window to save energy. Hanging type energy saving window film may comprise a hook system, a roller curtain system, or a motorized roller curtain system.
摘要:
Dipeptidyl peptidase IV (DPP-IV)-inhibiting compounds are provided that have formula I: wherein n is 1 to 3; X is CH2; S; O; CF2 or C(CH3)2; Z is H; halogen; hydroxyl; (C1-6)alkoxy; (C1-12)alkyl; (C3-12)cycloalkyl; phenyl; or heteroaryl; where the phenyl and heteroaryl groups are optionally mono- or independently plurisubstituted with R7; optionally, X together with an adjacent ring carbon and Z form a fused cyclopropyl; and optionally, one of the bonds in the ring containing X is a double bond; and CRiRii, R1, R2, R3, R4 and R5 are as described herein.
摘要:
Various embodiments of decoding systems and methods are disclosed. One system embodiment, among others, comprises a macroblock decode module configured to decode a plurality of context adaptive binary arithmetic coding (CABAC) encoded symbols corresponding to a slice without processor intervention.