Papers by Keyword: Electrical Contact

Abstract: The paper describes the method and results of laboratory tests with several types of demountable contact joints and operation tests at functional power industry facilities. The contacts without protective coating are compared with contacts with the protective light-alloy-based coating applied according to the authors’ technology. It is demonstrated that the technology is applicable in real electric equipment operation conditions.

Abstract: The paper analyzes a technology allowing the improvement of such performance characteristics of contact joints as reliability and operating economy, with demountable contact joints taken as an example. The performance characteristics are improved through applying protective metal coatings based on low-melting alloys on the contact members working surfaces. The paper describes the process of alloys selection as well as the development in the technology of the material application onto the contact members.

Abstract: Contact resistance is one of the key parameters of main bus bar. The bus performance is decided by the value of Contact resistance. By test of the typical rectangular copper bus-bar, it is analyzed that the effects of force on DC contact resistance. The results show that metal surface contact resistance decreases with the increment of pressure. The resistance is mental nature property, which is determined by material’s performance. At the same time the effect of contact distance is studied in detail.

Abstract: Study on contact resistance is a fundamental content of electrical contact field. The causes of contact resistance are complex, and a reasonable theoretical model poses significant impacts on the study and practical application of contact resistance. This paper describes the generating mechanism and components of contact resistance, highlights the summary on the development of the model, and gives the calculation method of contact resistance in practical engineering application.

Abstract: In the paper the actual state and prospects of applicability of a high power electron beam technology for manufacturing metallic as well as nonmetallic composite materials mostly for electric contacts and electrodes are presented and discussed

Abstract: Keywords: electrical contact lubricant contact resistance sliding wear Abstract. The contacts must be reliable in the required life time under practical application. Reliability means that the contact resistance can maintain low and stable. Au-plated contact pairs have been used widely for weak current connectors due to its well electrical and anti-corrosion performance. The high price of gold forces manufacturers to reduce the thickness of Au-plated while maintaining well performance. Increasing thin of Au plating causes the microporosity to increase rapidly, which has harmful effect on the performance of connectors. Appropriate lubricant coated on contact pair is a solution to improve the contact property. This paper focuses on sliding contact performance of gold plated contact pairs coupon with 0.25 m thickness and lubricated with water based lubricant named lub-E under damp heat and corrosion environment respectively. The contact pairs are also exposed in damp heat, corrosion environment respectively to evaluate the anti contamination property. The sliding experiment is conducted at frequency of 1Hz, amplitude of 1cm, and load of 0.5N, 1.0N and 1.5N. Contact resistance data is gotten in every sliding cycle at the condition of DC current 100mA and limited voltage 1.0V. Scanning electron microscopy (SEM) is used to observe the sliding track morphology and X-ray energy dispersive spectroscopy (EDS) is used to analyze the element.

Abstract: Comfort, safety, communication, control with assistance (antilock brake system, seat heating, multi-media, etc...) and safeguarding the environment are many factors which are included in the new generation of vehicles. The increase in the number of electronic and electric system leads to a high level of vehicle control. To answer this high electric power demand, it will be necessary to triple the voltage of the batteries (from 14 to 42 Volts). The objective of this work is to study the arc phenomenon which can occur in an accidental way during the use of a high electric power and particularly during the extraction phase of the male part from the female part of the automotive connector. It was observed that this can be characterized by both its energy and by its temperature. The amplification of the contact current from 14 to 42 VDC considerably increases arc damage.

Abstract: In this paper are presented the experimental results regarding the elaboration of electrical contacts using W-Cu composite powders obtained by mechanical alloying (MA) process. For the research commercial powders with a particle size between [10-80] µm were used. Three types of mixtures with different concentrations as follow: 90W-10Cu; 80W-20Cu; 70W-30Cu were mechanically alloyed for 2 up to 6 hours using a planetary ball mill. The mixtures obtained after MA process were pressed in a cylindrical die at 400 respective 600 MPa. The evolution of green densities function the compaction pressure and Cu content was studied. The green billets were sintered in an electrical furnace at 1180 oC and maintained 60 minutes at the sintering temperature in argon atmosphere. The evolution of densities, microstructures and electrical properties of the sintered samples function the Cu content and compaction pressure were studied.

Abstract: Electrical contractor affects reliability and working life of switches and electrical equipment directly, which is the key component of high-voltage and low-voltage apparatus. Nowadays, all fields of mid-voltage and above are occupied by vacuum switch. The invention of contactor material CuCr promotes the development of electrical contractor material and vacuum switch though the weakness can not be ignored. This paper makes a study and analysis about the performance of traditional electrical contractor material WCu. Its believed that alloy WCu has the high conductivity and high thermal conductivity of W, and the ability to improve applying condition and reduce electrical corrosion of Cu. So the experiment is made to test electrical characteristics of material WCu which is doping with different element. The performance of a new electrical contractor material, named Ti₃SiC₂, which is better than alloy WCu is put forward. This material meets the requirement, including high voltage, huge capacity, small scale, for switching equipment to develop grid, as the new material has advantage of low density, high modulus, high melting point, and antioxidant and so on. The successful application improves its superiority in the field of electrical contractor material.

Abstract: This paper takes metal-insulator-metal system as example and investigates the main types of electrical contact through the view of energy band structure, to analyze the whole process of the transition from ohm contact to barrier contact. Ohm contact, which promotes charges injection from electrode (metal) to insulator, can be used as storage of charge carrier, which is body limited; it can also be regarded as a type of contact that forms an accumulation layer extending from the interface to the interior of the insulator. Whereas, barrier contact is a type of contact which forms a depletion region extending from the interface to the interior of insulator. As for this type of contact, electron injection from metal tends to the state of saturation. The characteristic of neutral contact is that there is no space charge in the insulator, nor band bending, which means the boundary of conduction band and valence band up to the interface is flat.