Error Analysis for Metering Current Transformer with DC Bias

2013 ◽  
Vol 773 ◽  
pp. 58-61
Author(s):  
Shi Hai Yang ◽  
Ke Qi Zhang ◽  
Zhong Zhuang ◽  
Min Rui Xu ◽  
Min Jian Cao ◽  
...  
Keyword(s):  
Error Analysis ◽  
Power System ◽  
Simulation Model ◽  
Digital Simulation ◽  
Current Transformer ◽  
Angle Error ◽  
Ratio Error ◽  
Dc Bias ◽  
Simulation Results ◽  
Different Levels

DC bias widely exists in power system. In order to analyze its influence on metering current transformer (MCT), a new digital simulation model based on Preisach theory is constructed firstly. Using this digital model, the ratio error and angle error of a running MCT are calculated under different levels of DC bias. Simulation results show that the current DC bias in power system has only little influence on the error of MCT.

scholarly journals The Research on Anti-DC current Transformer of Dual Iron Core Structure with Air Gap

2021 ◽  
Vol 2133 (1) ◽  
pp. 012030
Author(s):  
Zhongai Lin ◽  
Xingyi Zhang ◽  
Biao Tang ◽  
Feng Shen
Keyword(s):  
Electrical Measurement ◽  
Current Transformer ◽  
Air Gap ◽  
System Stability ◽  
Iron Core ◽  
Saturation Current ◽  
Angle Error ◽  
Ratio Error ◽  
Dc Bias ◽  
Dc Current

Abstract Current transformer (CT) is wildly used in electrical measurement and relay protection. In order to improve the power system stability in DC bias, the CT performance of anti-DC is necessarily to be enhanced. Based on the Jiles-Atherton theory, the magnetization characteristics of iron core with different air gap was analyzed in this paper. A simulation model was established using the Simulink toolbox, and the ratio error and angle error were investigated in different air gap length. Simulation result shows that the maximum magnetic density of iron core almost stays uncharged with the addition of air gap. Furthermore the slope of magnetization curve decreased, which leads to the increase of iron core saturation current. Current transformer with closed and air gap iron core possesses a stable measurement error in condition of severe DC bias.

Study of an accurate electronic power measurement technique using modified current transformer and potential transformer

2019 ◽  
Vol 41 (13) ◽  
pp. 3666-3678
Author(s):  
Sirshendu Saha ◽  
Saikat Kumar Bera ◽  
Hiranmoy Mandal ◽  
Pradip Kumar Sadhu ◽  
Satish Chandra Bera
Keyword(s):  
Phase Angle ◽  
Measurement Errors ◽  
Light Emitting Diode ◽  
Current Transformer ◽  
Power Measurement ◽  
Measurement Unit ◽  
Measurement Circuit ◽  
Angle Error ◽  
Ratio Error ◽  
High Tension

In high tension power measurement, potential transformer (PT) and current transformer (CT) are used in order to reduce high tension voltage and current, respectively. But both PT and CT suffer from ratio error and phase angle error, which may produce severe error in power measurement. In the present paper, modified designs of PT and CT are combined to develop an electronic power measurement circuit in order to reduce the measurement errors. The modified PT and CT have reduced phase angle error and ratio error. In the power measurement circuit, the instantaneous product of the outputs of these PT and CT is determined by using a simple light emitting diode (LED)-light dependent register (LDR) or LED-LDR-based product circuit. The operation of the proto type power measurement unit designed in the present work has been experimentally tested and the measured outputs are compared with the readings of laboratory standard wattmeter. The experimental results are reported in the paper. Very good linear characteristics are observed.

Simulation and Analysis for Current Transformers with DC Bias and Remnant Flux

2013 ◽  
Vol 765-767 ◽  
pp. 2430-2434
Author(s):  
Xiao Qian Tian ◽  
Bao Shu Li ◽  
Lu Shen
Keyword(s):  
Error Compensation ◽  
Current Transformer ◽  
Scientific Basis ◽  
Current Transformers ◽  
Ratio Error ◽  
Full Wave ◽  
Accuracy Of Measurement ◽  
Dc Bias ◽  
Power Metering ◽  
Fourier Algorithm

The transfer characteristics of current transformers (CT) change due to DC bias, which directly impacts the accuracy of measurement and power metering. Based on equivalent circuit models and core magnetizing characteristic, qualitatively analysis current transformer saturation increase errors of CT. Transfer errors under DC bias and remnant flux are also obtained based on J-A model of CT in PSCAD/EMTDC and full-wave Fourier algorithm to show that the ratio error and phase displacement increase with the DC bias. Based on FFT spectrum analysis to identify remnant flux and DC bias provides scientific basis for error compensation of CT.

scholarly journals Analysis And Study On Distribution Of Defect Electric Field On Basin-type Insulator In GIS

2018 ◽  
Vol 53 ◽  
pp. 01015
Author(s):  
Qikun Feng ◽  
Nianqin Dai
Keyword(s):  
Electric Field ◽  
Power System ◽  
Simulation Model ◽  
High Voltage ◽  
Electric Network ◽  
Operation And Maintenance ◽  
Field Distortion ◽  
Actual Operation ◽  
Simulation Results ◽  
Gas Insulated Substation

With the increase of electric network voltage in power system, the internal discharge phenomenon of gas insulated substation (GIS) during operation often happens. In this paper, a 3-D simulation model of GIS with metal protrusion on basin-type insulator was utilized to study the effect of metal protrusion on the electric field distortion in GIS. It can be concluded from simulation results that the electric field increases with the height of metal protrusion when the radius is constant, while decrease with the increase of radius of metal protrusion. In addition, the metal protrusion near high voltage conductor lead to more severe electric field distortion than that near grounded enclosure. This work is of significance for the actual operation and maintenance of GISs in the power system.

Nonlinear Model and Digital Simulation Analysis of Valve Controlled Cylinder Base on Power Bond Graph

2011 ◽  
Vol 80-81 ◽  
pp. 841-844
Author(s):  
Ling Yu ◽  
Yan Chun Zhao ◽  
Chun Qiang Jia
Keyword(s):  
Simulation Model ◽  
Nonlinear Model ◽  
Dynamic Characteristics ◽  
Simulation Analysis ◽  
Digital Simulation ◽  
Bond Graph ◽  
Scientific Basis ◽  
Slide Valve ◽  
Power Bond Graph ◽  
Simulation Results

In this paper the nonlinear model of zero open symmetrical cylinder controlled by four-way slide valve system was established base on power bond graph. The flexible simulation model was building up by the use of simulink toolbox in MATLAB. The model’s dynamic characteristics were stimulated. The simulation results showed the nonlinear model could reflect the dynamic characteristics of the valve controlled cylinder accurately. So it provided scientific basis for estimating the characteristics and correct using of the controlled cylinder system.

Design and Simulation of Power System for Hybrid Sweeper Truck

2013 ◽  
Vol 389 ◽  
pp. 435-440
Author(s):  
Bing Li Zhang ◽  
Lun Zhen Wang ◽  
Fu Bin Xiao ◽  
Xin Ying Ou
Keyword(s):  
Power System ◽  
Simulation Model ◽  
Fuel Consumption ◽  
Hybrid System ◽  
Fuel Economy ◽  
Control Strategy ◽  
Hybrid Power System ◽  
Hybrid Power ◽  
Simulation Results ◽  
And Control

A hybrid system scheme was designed for the sweeper truck, to solve the problems of high fuel consumption and poor emission performance of traditional sweeper. The control strategy was determined for the hybrid power system. The simulation model of hybrid sweeper truck was built with Matlab/Simulink, and off-line simulation was completed to verify the power system scheme and control strategy, the simulation results indicate that the hybrid sweep truck can realize functions of sweeper and improve the fuel economy.

Influence of DC Bias and Remnant Flux on Measuring Current Transformers

2013 ◽  
Vol 765-767 ◽  
pp. 2268-2271
Author(s):  
Lu Shen ◽  
Shu Tao Zhao ◽  
Pei Zhang ◽  
Bin Hu ◽  
Xiao Qian Tian
Keyword(s):  
Power Systems ◽  
Electric Energy ◽  
Current Transformer ◽  
Simulation Software ◽  
Ratio Error ◽  
Phase Displacement ◽  
Limit Value ◽  
Exciting Current ◽  
Energy Metering ◽  
Dc Bias

Current transformer (CT) is an important transmission equipment in power systems. DC bias and remnant flux can change the working point of CT in the core magnetization curve and has a direct impact on the accuracy of electric energy metering and measurement. The simulation circuit model is built by using the simulation software PSCAD and the change of ratio error, phase displacement and exciting current with DC bias and remnant flux are analyzed. The results show that DC bias and remnant flux will both increase the ratio error and phase displacement in opposite directions and the error size will be far more than the limit value when DC bias and remnant flux exist in same direction at the same time. Furthermore, the existence of DC bias and remnant flux will also cause the raise of exciting current size, asymmetry of exciting current waveform and appearance of even harmonics. This will seriously affect the transmission accuracy of measuring CT.

Research on Automatic Controlling Method of TSC+TCR Typed Dynamic Reactive Power Compensation

2015 ◽  
Vol 1092-1093 ◽  
pp. 321-324 ◽  
Author(s):  
Ming Zhao ◽  
Shi Fu Zhang ◽  
Bin Yi ◽  
Xiao Qin Zhang ◽  
Dong Mei Zhang
Keyword(s):  
Control System ◽  
Power System ◽  
Simulation Model ◽  
Real Time ◽  
Power Factor ◽  
Reactive Power ◽  
Reactive Power Compensation ◽  
Primary System ◽  
Compensation Control ◽  
Simulation Results

A simulation model of 230kV substation primary system and TSC+TCR typed dynamic reactive power compensation control system was constituted with RTDS, and the feasibility of control system with a case was validated. The control system was to monitor the variation of power system equivalent susceptance with sampling the power system voltage, established the relationships between power system susceptance and the firing angle of TCR, adjusted TSC switch and TCR firing angle to dynamically compensate the reactive power of power system. The simulation results demonstrate that the control system can guarantee power system voltage stability and real-time adjust power factor.

Excess Inventories and Stock Out Events Through Advanced Demand Analysis and Emergency Deliveries

2018 ◽  
pp. 176-193
Author(s):  
Rania Tegou
Keyword(s):  
Error Analysis ◽  
Simulation Model ◽  
Daily Basis ◽  
Demand Analysis ◽  
Analysis Model ◽  
Sales Data ◽  
Alternative Approach ◽  
Tangible Product ◽  
Different Levels

Companies have to deter many remarkable problems on a daily basis. The existence of excess inventories and stock out events as well the usage of emergency deliveries are three indicative prominent subjects for discussion. Firms try to comprehend the consumer's desires in order to enhance costumer experience. In the current chapter, sales data of one tangible product from a well-known Greek retailing company are used. These data are analyzed in order to forecast the behavior of the demand. The author adapts an alternative approach for managing inventory during cycles with different levels of demand in order to develop a system that minimizes both excessive inventories and stock out events. Additional experiments take place regarding the parameterization of emergency deliveries in order to configure whether their usage is beneficial. Both an error analysis model and a simulation model are developed so as to determine the results of the aforementioned action.

scholarly journals A Digital-Simulation Model for a Full-Polarized Microwave Radiometer System and Its Calibration

2021 ◽  
Vol 13 (23) ◽  
pp. 4888
Author(s):  
Jia Ding ◽  
Zhenzhan Wang ◽  
Yongqiang Duan ◽  
Xiaolin Tong ◽  
Hao Lu
Keyword(s):  
Error Analysis ◽  
Simulation Model ◽  
Input Signal ◽  
Digital Simulation ◽  
Microwave Radiometer ◽  
Surface Wind ◽  
Surface Wind Speed ◽  
Stokes Parameters ◽  
Calibration Matrix ◽  
Signal Models

A digital-correlation full-polarized microwave radiometer is an important passive remote sensor, as it can obtain the amplitude and phase information of an electromagnetic wave at the same time. It is widely used in the measurement of sea surface wind speed and direction. Its configuration is complicated, so the error analysis of the instrument is often difficult. This paper presents a full-polarized radiometer system model that can be used to analyze various errors, which include input signal models and a full-polarized radiometer (receiver) model. The input signal models are generated by WGN (white Gaussian noise), and the full-polarized radiometer model consists of an RF front-end model and digital back-end model. The calibration matrix is obtained by solving the overdetermined equations, and the output voltage is converted into Stokes brightness temperature through the calibration matrix. Then, we use the four Stokes parameters to analyze the sensitivity, linearity, and calibration residuals, from which the simulation model is validated. Finally, two examples of error analysis, including gain imbalance and quantization error, are given through a simulation model. In general, the simulation model proposed in this paper has good accuracy and can play an important role in the error analysis and pre-development of the fully polarized radiometer.

Sign in / Sign up

Export Citation Format

Share Document