Robust Optimization Design For The Transmission System Of Low-Voltage Vacuum Circuit Breaker

A vacuum circuit breaker developed in the early 1960s with the advantages of no fire, zero pollution, high life, no altitude restrictions and excellent breaking performance, etc., has been widely used and become dominant in the medium voltage (10-35kV) power system of China, but not yet got a lot of promotion in the low voltage (< 1140V) field because of many limiting factors.Currently, contact opening distance and pre-vibration during operation are two key issues that constrain the development progress and technical level of low-voltage vacuum circuit breaker. The design quality of entire linkage system including operating mechanism has a close relationship with them. However, the domestic vacuum circuit breakers are still at the stage of introduction and analogy design as well as lack of guidance on reliability design theory and methods. Against this background, according to the characteristics of vacuum circuit breaker such as a small contact opening distance and mutation load, it is very significant both in theory and practice to carry out research and design on the linkage system from the angle of force and movement, which help to further improve product quality and market competitiveness.This subject is based on the development of a certain type of low-voltage vacuum circuit breaker. First, current status on the development and mechanical reliability research of vacuum circuit breaker at home and abroad is investigated, by which the paper points out and analyzes the main problems existing in the present technological innovation and the key to solve. Then, after studying reliability theory and design methods, a reliability design idea of the transmission system based on robust optimization and implementation methods is proposed for low-voltage vacuum circuit breaker. The detailed method is that, firstly according to the desired product key technical parameters, on the basis of a detailed study for both physical mechanism and influence factors including mechanical property of breaking arc, an overall scheme of the transmission system is determined by comparison and synthesis of existing mature technology programs, especially the rear linkage is completed preliminarily to satisfy the requirements of displacement by applying mechanical theory, and its properties of kinematics and mechanics are analyzed by building a mathematical model. Finally, this paper studies and expounds the reliability theory and optimization design method, based on which the above link mechanism is robustly optimized. We focus on selecting a few of important parts that affect product performance for analysis and calculation, and some key parameters is optimized after experimental research, which eventually make the transmission system meet the design requirements of product performance.Mechanical characteristic measurement proved that the breaker got excellent kinematic and dynamic characteristics by means of carrying out robust optimization design and research for the transmission system, which guarantees the ability to making and breaking short circuit current of product.With the development of national economy and the progress of science and technology, the application of low-voltage vacuum circuit breaker will be more to a wide range, which offers higher demands for its performance and robustness. This subject will open up a practical and effective path of combining theory and practice to improve product technology, help to improve the quality and market competitiveness of product, create value for society, and enhance our country’s technological prowess.