Articles

Found 6 Documents
Search

Ventilation Structure Improvement of Induction Motor Using Multiphysics Simulations Zhang, Yujiao; Huang, Xiongfeng; Huang, Tao; Ruan, Jiangjun; Wu, Xiaowen
TELKOMNIKA Indonesian Journal of Electrical Engineering Vol 10, No 3: July 2012
Publisher : Institute of Advanced Engineering and Science

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.11591/telkomnika.v10i3.605

Abstract

Temperature rise analysis has significant impact in the design of air-cooled asynchronous induction motor. However, the affection cannot be accurately evaluated by using traditional empirical curves method due to the complexity of the inductor architecture. Considering Joule’s losses in stator windings and the induced eddy current in squirrel cages, and heat dissipation by air convection and solid conduction, in this paper a 3-D coupled-field finite-element method (FEM) is investigated to demonstrate the temperature distribution. The Joule’s losses calculated by 3-D eddy- current field analysis are used as the input for the thermal field analysis, which is deeply dependent on accurate air fluid field analysis. A novel multi-component fluid model is employed to deal with the influence of rotor rotation upon the air convection. The simulation results show the fatal influence of the ventilation structure and the effectiveness of the proposed cooling improvement way.  
Influencing Factors of Breaking Capacity of Double-Break Vacuum Circuit Breakers Shu, Shengwen; Ruan, Jiangjun; Huang, Daochun; Wu, Gaobo
TELKOMNIKA Indonesian Journal of Electrical Engineering Vol 11, No 6: June 2013
Publisher : Institute of Advanced Engineering and Science

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.11591/telkomnika.v11i6.2140

Abstract

Using a series arrangement of two vacuum interrupters (VIs) has been proved to be an effective way of developing higher voltage vacuum circuit breakers (VCBs), which are known as double-break VCBs. The uniform distribution of the transient recovery voltage (TRV) across each VI is very critical for the breaking capacity of double-break VCBs. In this paper, the TRV distribution characteristics of double-break VCBs was studied by the synthetic test and the PSCAD/EMTDC simulation based on a vacuum arc interruption model. The results show that the bias of the TRV distribution ratio is caused by the stray capacitance and the imbalanced post arc plasma characteristic in each VI, which is consistent with the theoretical analysis. Moreover, the negative effect of grading capacitors was discussed. The results show that it is advisable to limit the value of grading capacitors to those ranges which can guarantee sufficiently improve the voltage distribution.
Assessment of Intelligent Substation Based on an Improved Fuzzy Sets Method Hu, Yuanchao; Yao, Lina; Ruan, Jiangjun; An, Yunzhu; Chen, Fan
TELKOMNIKA Indonesian Journal of Electrical Engineering Vol 12, No 10: October 2014
Publisher : Institute of Advanced Engineering and Science

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.11591/telkomnika.v12i10.5334

Abstract

In the construction process of smart grid, an assessment on primary equipments intelligent transformation is an urgent content in the first batch of intelligent substation pilot project. Wide investigation of intelligent substation pilot projects was conducted seriously in several regional power grids in China. An mathematical model was established to assess the substation primary equipments intelligent transformation firstly; then, the Vague sets multi-objective decision theory was applied to the assessment model and the consistency inspection and weight solving method of Vague set theory was improved in this paper. Finally, a practical example was given to show the rationality and accuracy of the above improved method. The method can provide practical guidance to assess primary equipments intelligent transformation.
Study of Economical-Technical Impacts of Distributed Generation on Medium-Voltage Grid Nguyen, Thi Dieu Thuy; Ruan, Jiangjun; Nhu Nguyen, Quan; Giang Le, Ngoc; Tan, Dan; Hu, Longfei
TELKOMNIKA Indonesian Journal of Electrical Engineering Vol 12, No 2: February 2014
Publisher : Institute of Advanced Engineering and Science

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.11591/telkomnika.v12i2.3796

Abstract

The development of Science and Technology has spurred the development of distributed generation, as well as the application of new renewable energy sources. DG connected to the grid can alter the power flow on the grid, reduce voltage loss and grid capacity loss; and also enhance the incident and reliability of grid power supply. When the number of DG connected to the grid increases, capacity direction varies depending on the distribution and consumption at specific time. Consequently, capacity losses in the grid can be reduced. Besides, DG connected to the grid is closely linked to the matters of environmental pollution and degradation, economic growth and living standard. This paper will discuss the impacts of grid-distributed generation on economic and technical indicators, which mainly focus on the relationship between degree of penetration and location of DG connection to the grid, regarding voltage and capacity losses in the line. The proposed model is calculated and tested via a 56-bus radial distribution system in the DELPHI7 programming language.
Simplification Study of FE Model for 1000kV AC Transmission Line Insulator String Voltage and Grading Ring Surface Electric Field Distribution Calculation Wang, Guoli; Zheng, Zheng; Huang, Daochun; Huang, Zhengfang; Ruan, Jiangjun; Liao, Yifan
TELKOMNIKA Indonesian Journal of Electrical Engineering Vol 12, No 2: February 2014
Publisher : Institute of Advanced Engineering and Science

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.11591/telkomnika.v12i2.3833

Abstract

The finite element model of the 1000kV Ultra High Voltage (UHV) AC transmission line porcelain insulator string voltage distribution and grading ring surface electric field distribution calculation has the characteristics of large size, complicated structure and various mediums. To insure the accuracy, related influencing factors should be considered to simplify the model reasonably for improving computational efficiency. A whole model and a simplified 3D finite element model of UHV AC transmission line porcelain insulator string were built. The influencing factors including tower, phase conductors, hardware fittings, yoke plate and phase interaction were considered in the analysis. And finally, the rationality of the simplified model was validated. The results comparison show that building a simplified model of three-phase bundled conductors within a certain length, simplifying the tower reasonably, omitting the hardware fittings and yoke plate and containing only single-phase insulator string model is feasible. The simplified model could replace the whole model to analyze the voltage distribution along the porcelain insulator string and the electric field distribution on the grading ring surface, and it can reduce the calculation scale, improve optimization efficiency of insulators string and grading ring parameters.
Ventilation Structure Improvement of Induction Motor Using Multiphysics Simulations Zhang, Yujiao; Huang, Xiongfeng; Huang, Tao; Ruan, Jiangjun; Wu, Xiaowen
TELKOMNIKA Telecommunication, Computing, Electronics and Control Vol 10, No 3: September 2012
Publisher : Universitas Ahmad Dahlan

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (51.295 KB)

Abstract

Temperature rise analysis has significant impact in the design of air-cooled asynchronous induction motor. However, the affection cannot be accurately evaluated by using traditional empirical curves method due to the complexity of the inductor architecture. Considering Joules losses in stator windings and the induced eddy current in squirrel cages, and heat dissipation by air convection and solid conduction, in this paper a 3-D coupled-field finite-element method (FEM) is investigated to demonstrate the temperature distribution. The Joules losses calculated by 3-D eddy- current field analysis are used as the input for the thermal field analysis, which is deeply dependent on accurate air fluid field analysis. A novel multi-component fluid model is employed to deal with the influence of rotor rotation upon the air convection. The simulation results show the fatal influence of the ventilation structure and the effectiveness of the proposed cooling improvement way.