Estimation of abnormal states in shunt capacitor banks using transient disturbance feature extraction Long Zhang1, Ming Ma2, Wen Xiao3*, Yunping Zhong1,BiHu1, Wenwen Zhou1 and Wenhai Zhang3 1Heyuan Power Supply Bureau of Guangdong Electric Power Grid Co., Ltd., Heyuan, Guangdong Province, China, 2Electric Power Research Institute of Guangdong
The capacitors in AC filters, made up of multiple small capacitors in series and parallel, can retain residual charge and voltage if flashovers occur in some capacitors. Moreover, due to the capacitors'' memory effect, rapid re-closing of the AC filter shortly after system operation can result in residual voltage, leading to
Calibration is compulsory before connecting the CVT to the grid, which is called the acceptance test, and is carried out every four years in the operation process, which is called the periodical on-site calibration [9].
Through the analysis and processing of common faults of power capacitors, it is possible to timely understand and master the operation of capacitors, detect capacitor defects in time and take
An abnormal alteration in the measurement error state of CVT is manifested by a discernible deviation in the projection of measurement data within the pivot subspace and residual subspace.
We analyze the waveform characteristics of fault transient processes on the key monitoring points of shunt capacitor banks, derive and analyze the quantitative relationship between the key parameters of the
Then, disturbances are classified as switching, fault, or abnormal operations, according to the cause. The characteristics of various typical disturbance waveform data
Highlights • Capacitor sudden failure detection method based on parameter mutation. • Parameter estimation method of aging model based on Bayesian linear regression.
Signal processing-based detection methods proposed in existing literature fail to eliminate primary side power grid fluctuations [7] [8] [9], risking misjudgments or omissions during prolonged monitoring. swayed by the prolonged operation of the Capacitor Voltage Transformer (CVT) and structural malfunctions, its factual transformation
in research and industrial practice of abnormal event management (AEM) and process safety. Chapter 2 focuses on monitoring and man-aging safety during online process operation hence reporting methodologies for monitoring, detecting and diagnosing abnormal events dur-ing process operation. Chapter 3 takes a step back and focuses on
Octree based visual monitoring method for operation process of power construction site. Author links open overlay panel Chao Zhang, Lihua Zhang, Xu Chen, Once abnormal behavior or events are detected, the system will immediately trigger an alert and display real-time information such as the target''s position and movement trajectory through
capacitor banks are valuable assets that must be available for the daily demands of system operation and must provide reliable operation through abnormal power system scenarios. From the protective relaying perspective, however, capacitor banks are historically considered a relatively low-volume market, and therefore, did not encourage
Therefore, a method of capacitor self-healing failure protection based on active power variation was proposed. 1 Introduction. This test process is basically equivalent to the self-healing failure process that occurs during actual operation. This test method is equivalent to dividing the self-healing failure process into two independent
process of CVT, due to the influence of design level, manufactu ring process, sy stem operation and other factors, the faults of electrical components such as upper and lower capacitors
The proposed monitoring method can effectively identify the abnormal capacitor state and accurately calculate the capacitance value. Moreover, the proposed method does not affect the normal operation of the MMC. Finally, simulation analysis and experimental validation are performed to verify the effectiveness of the proposed method.
For long-term monitoring and observation of the capacitor capacitance value, the fault state and abnormal state of the capacitor are identified based on statistical methods.
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If the operation process, found the capacitor bank protection of unbalanced voltage action, conventional tests check without exception, should first consider checking the voltage ratio between the primary and the secondary of the discharge coil. Fault analysis and treatment method of the case;
The invention discloses a kind of method processing abnormal MIM capacitor dielectric layer, it is characterised in that comprise the following steps: step one, measure and abnormal MIM...
A number of abnormal events can cause unsafe operation, including a high impedance fault (HIF), a partial breakdown to a cable insulation, and a circuit breaker (CB) malfunction due to capacitor
With this method, the measurement error exceeding the limit of capacitor voltage transformer can be detected online without a power outage. The simulations have shown that
Highlights • Detect the CVT with abnormal measurement in real-time without power outages. • The regulation for determining abnormal CVT is its error surpass the limits. •
The application discloses a capacitor bank operation harmonic environment monitoring method, a device and equipment, which are used for monitoring the secondary voltage of a capacitor bus mutual inductor and the secondary current of a capacitor current mutual inductor in real time, correcting the secondary voltage by adopting a transient overvoltage back-calculation method
Due to improper handling methods, the porcelain casing is pulled, causing cracks in the flange weld, or the force of tightening the nut during wiring is too large, causing
The overall objective of this study is to devise a non-invasive, online condition monitoring technique of circuit-switchers for shunt capacitor banks. It aims to detect abnormal operation of these
The results strongly suggest the advantages of CNN method for sensor abnormal signal processing and provide a solid foundation for the reliable use of sensors in such type of problems. NN structure.
et al. [12] extracted features from the historical operation data of EVs and described battery degradation. However, few studies have focused on the abnormal capacity change fault diagnosis and parameter calibration. Despite the existence of several charging protection measures, the abnormal charging capacity of the power battery leads to
TVUR correlation curve: (a) single-phase voltage deviation curve, (b) timing correlation of phase A voltage deviation.
By comparing Table 2 with Table 1, it is evident that the performance of waveform identification methods without PAA processing generally decreased compared to those that utilized PAA processing, thus confirming the effectiveness of the PAA method. Additionally, under conditions without PAA processing, the performance decline was more pronounced for SVM, KNN, and
A Prediction Method for Abnormal Condition of Scheduling Plan with Operation Time Delay in Steelmaking and Continuous Casting Production Process Shengping YU* State Key Laboratory of Synthetical Automation for Process Indu stries, Northeastern University, Shenyang, Liaoning Province, 110819 P. R. China.
The overall objective of this study is to devise a non-invasive, online condition monitoring technique of circuit-switchers for shunt capacitor banks. It aims to detect abnormal operation of these
According to the high-voltage and small-current characteristics for unbalanced current of high-voltage capacitors, a novel fiber optical filter unbalanced current transformer (FU-FOCT) is...
calculate the power losses as also an iteration process to estimate the capacitor temperature. 2.2. Lifetime model and Damage accumulation Failures in e-caps may occur due to external and/or random factors such as manufacturing defect, improper design, environmental overstress, abnormal operation condition, among others. These, however,
Common Faults and Treatment Methods of Power Capacitor . Li Guangda. 1, Zhao Qiang. 2, Xu Mei. 2, Jin Jing. 2, Zhang Fuliang. 2 operation, if the capacitor is found to be "beep", it is a precursor to the internal insulation When an abnormal noise occurs in the capacitor during operation, partial it indicates that
The capacitor unit structure is shown in Figure 1, where each capacitor unit consists of several elements in series and parallel. Each capacitor element is series-connected to the internal fuse. When a single capacitor
dielectric layer of a capacitor near the edges or seams. In all cases the capacitor on the voltage control line of the VCO failed. In addition, destructive and nondestructive capacitor stress testing methods were studied. Keywords—capacitor, subtractive thermal IR, FIB, stress testing I. INTRODUCTION An externally purchased VCO has had an
Various implementations described herein relate to systems and methods for determining abnormal leakage current of a capacitor by determining a number of recent leakage current values for the capacitor and determining a maximum upper limit, minimum upper limit, maximum lower limit, and minimum lower limit based on leakage current values different from the recent
The split link capacitor topology requires six switches and two capacitors. However, the split link capacitor topology suffers from poor voltage balancing between the two
Capacitor defects significantly contribute to infant and latent failures in integrated circuits. This paper will address methods of locating capacitor defects and root cause determi-nation. Keysight Technologies’ failure analysis team investigated tens of failures in an externally purchased voltage controlled oscillator (VCO).
Advancements in failure analysis have been made in root cause determination and stress testing methods of capacitors with extremely small (approximately 200 nm) defects. Subtrac-tive imaging has enabled a non-destructive means of locating a capacitor short site, reducing the FIB resources needed to analyze a defect.
Keysight Technologies’ failure analysis team determined the root cause of these failures to be voids in the capacitor dielectric layer. The voids allowed the propagation of metal into the dielec-tric layer. This metal migration led to latent failures in the field.
The root cause was found to be voiding in the dielectric layer of a capacitor near the edges or seams. In all cases the capacitor on the voltage control line of the VCO failed. In addition, destructive and nondestructive capacitor stress testing methods were studied.
Subject The assessment of the measurement error status of online Capacitor Voltage Transformers \(CVT\) within the power grid is of profound significance to the equitable trade of electric energy and the secure operation of the power grid.
This paper posits an online Capacitor Voltage Transformer (CVT) error state evaluation methodology predicated on the inphase relationship and the ident- i- fication of aberrant points.
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