10kV Switchgear Structure Optimization Design Based On The Temperature Rise Test

With the promotion of the use of metal-enclosed high voltage switchgear, the switchgear’s heating problem has become increasingly prominent, has led to a series of accidents or malfunctions, resulting in switching equipment manufacturing industry is facing the development of more effective preventive measures to avoid such problems. The basic method to reduce the switchgear’s heating problem is to improve the switchgear’s design, technology or material. Simulation design has improved or explored the various boundary conditions to make a lot of simplifications, and has a large discrepancy of actual operation. Therefore, on the basis of the temperature rise test, this article make a structural optimization design of 10 kV switchgear for which switchgear is now generally run the current of 1250 A and maximum rated current of 3150 A, which provides a good measure to reduce the temperature inside the switch cabinet directly also as far as possible to consider reducing costs.Firstly,analyze the basic structure of the switchgear, find its main heat source: the main loop of electrical contacts and copper busbars. Then carry on the theoretical research from three ways of heat dissipations.Secondly,10 kV switchgear through the current of 1250 A specification from copper, we make improvements from the following aspects: static contact, the contact breaker claw plum number, busbar bending large open air hole, touch the wall breaker different materials. Copper TMY10X80 more secure and more reliable than TMY10X60; Replace conventional static contact oval with non-standard trapezoidal contacts, costs have not changed, the benefits are increased contact area static contact with copper, easing the branch and plum the temperature rise of contact points; in order to reduce the temperature rise of the circuit breaker, will increase the claw plums number from 8 to 12, so that the temperature rise point has eased; Comparing busbar bending large open air hole with standard conditions, this kind of convection experiment achieved the desired effect; the feasibility of circuit breaker copper aluminum touch the wall replaced pure copper touch the wall has been verified, basically meet the temperature requirements, the most important thing is cost saving for the volume production of enterprise.Thirdly,10 kV switchgear through the large current of 3150 A, the cost of switchgear is very high, so the measures of replace material or elements to improve the temperature rise is not feasible in practice. The main consideration of the switchgear structure optimized is the design of ventilation, so we designed seven programs to explore. The core idea is thermal convection and forced ventilation cooling.In this paper, based on the temperature rise test of 10 kV switchgear structure optimized design, now part of the measures have been applied in the actual real switch cabinet, not only saving costs for businesses, but also alleviate the problems caused by accidents and failures of the temperature rise.