Jia Jun Si

The Feasibility Research on the New Material Used in Electrical Fittings

Based on the requirements of The Twelfth Five Years development planning of State Grid and the development of electrical fitting, State Grid will enlarge the change of rural power network and power distribution market, which will make the coverage of rural power network and power distribution to be larger so that reducing the loss of the power transmission line will become an important task research. To reduce or replace the high energy consumption steel fittings and the high price aluminum fittings, this article make feasibility analyses for a new material used in electrical fittings to protect the environment and economy energy source, by analyzing the performance and test property of the new material.

Economic Analysis on Application of Large Section Conductor in Ultra-High Voltage DC Engineering

At present, large section conductors applied in domestic ±800kV ultra-high DC power transmission line consist of 6×720mm2, 6×900mm2 and 6×1000mm2 conductors. This paper analyzes initial engineering investment and mechanical performance of 6×JL1/G2A-720/50, 6×JL1/G3A-900/40, 6×JL1/G3A-1000/45, 6×JL1/G2A-1250/70 and 6×JL1/G2A-1520/125 conductor plans, carry out economic comparison of the whole life period of these 5 conductor plans, demonstrate economic of 6×JL1/G2A-1250/70, and 6×JL1/G2A-1520/125 conductor plans in ±800kV ultra-high DC power transmission line is more advantageous when annual loss hours is too high, and the 6×JL1/G2A-1250/70 plan can save initial investment of engineering compared to the 6×JL1/G2A-1520/125 plan.

Parametric Study on Simulation Modeling of Diameter-Expanded Conductor

So as to decrease the cost and time of the development, it is significance to solve the section instability problem of diameter-expanded conductor during the design stage. The solution is developing a finite-element simulation program for the study of section stability; however, a proper modeling method is not necessary. In this paper, the parametric study on simulation modeling of diameter-expanded conductor is carried out and through the investigation, analysis and verification; a kind of test method has been designed for the study. After a series of test under different tensions, the numbers of sheave, the position of strand jumping, the section states and the indentation states have been gotten. At last, a parametric finite-element program for strand jumping prediction has been simulated and the result shows that the code developed is reliable based on the comparison of the calculated results and the measured ones.

Vacuum Zincification Technical Study of Fitting Material in Power Transmission Line

Fittings of the power transmission line are requested to have good anti-corrosion performance when they are use at atmosphere environment. The fittings of the power line have certain mutual movement during application process, which mutually produce friction. In particular to the fittings of the power line which are applied in the area and environment with strong wind sand such as western area, wind sand will produce corrosion wear of the fittings in the line. Therefore the fittings of the power line are requested to have good anti-abrasion and corrosion resistant comprehensive performance. In combination with application environment of the power fittings and characteristics of vacuum zincification technology, carry out analysis on possibility of application of vacuum zincification in the fittings in the power line from performance requirements, fitting materials, geometrical features of the fittings, economy of vacuum zincification etc several aspects.

Simulation Research on Cross-Sectional Stability of Expanded Diameter Conductors Based on ANSYS

The expanded diameter conductors are widely used for high voltage electricity power transmission due to its superior ability to prevent electronic corona phenomenon. However an undesired stability problem of wire distribution configuration within the cross-section of the conductor often occurs during the power line stringing processes, especially for the not-well-designed conductor structures. This phenomenon is typically characterized by the appearance of outer wire/wires jumping out of the layer; therefore it is also referred as wire jump-out problem. Finite element model which can predict the wire jump-out phenomenon has been successfully developed in this research project. Series of stimulations have been carried out to investigate the key factors to cause the wire jump-out problem. The reduction of radial distances between the adjacent aluminum wire layers due to the obvious indentation deformation at the trellis contact points were identified to be one of the most significant factors to lead to the wire jump-out problem. Numerical results show that keeping sufficient initial gap between the adjacent outer layer wires in the initial design can be a simple effective way to relieve/avoid the wire jump-out problem.

Dynamic Analysis on Steel Tower of Vertical Axis Wind Turbine

The dynamic analysis has been adopted for the calculation of the low-order natural frequency and harmonic response data of the steel tower of vertical axis wind turbine, as well as the dynamic relation between the wind turbine and the tower. When the wheel rotates at 160rpm, the harmonic load has a very serious destructive damage to the tower. In order to avoid the system failure caused by the system resonance in the engineering design, some optimizations have been taken on satisfying the security and reliability of the tower. This study provides the scientific basis for the dynamic design and the optimization. The conclusion shows that the most effective method of raising the natural frequency is to reduce the weight of the structure when the material and the structural style are determined. As a result, the difference between harmonic response and resonance frequency of the structure rises to 21.3％ from 0.3％ after reducing the weight of the tower by 21.3％.