Design of an Intelligent Controller for Armature Controlled DC Motor using Fuzzy Logic Technique

This paper presents a fuzzy control approach to the speed control of DC shunt motor using armature control. This paper presents concept of development of conventional controller and the design of a fuzzy logic controller applicable to DC Motor Speed Control System (MSCS) with high performance of the FL controller. Since armature voltage supply has a major influence in controlling speed, therefore one of the inputs to the proposed FL Controller will be actual armature voltage supply (Va) while another input will be error (e) in speed. The transfer function model of the DC shunt motor has been obtained via experimentation and calculations and simulated and then as per requirement and specification, the proposed fuzzy logic controller has been designed and simulated using Fuzzy Logic and Simulink Toolboxes of MATLAB 7. Results show robustness against changing loading conditions

Electrodeposited nickel composites for high temperature applications

Although widely used because of its excellent physical and mechanical properties at room temperature on the one hand and its chemical and corrosion resistance on the other, nickel does not possess the wear resistance required for high temperature applications in many practical env~ronments.N umerous nickel base alloys have been developed for their strength and resistance at high temperatures. Recently nickel base composites, containing hard inert particles are receiving attention as possible wear resistant coatings for high temperature applications. In this paper, a critical analysis of the available composites are made for their usefulness for different applications as high temperature resistant as well as wear and corrosion resistant material

Studies on post-treatment of gold plated silver

Silver articles like jewellery, silverwares, cosmetic containers, novelties, presentation items etc. are usually plated with gold in very thin deposits to give good appearance and to protect silver from tarnishing. A verythin deposit of gold is often porous, and the silver tarnishes through the pores. This tarnishing will spread laterally over the gold and the whole component will turn black. This is often thought to indicate that the gold has tarnished, but this is not true. Thick layers of gold is useful in preventing tarnish films. However, it is very expensive. Other methods of reducing the tendency of silver to tarnish are to coat the surface with a special lacquer, grease, oil or wax or to apply special oxide or chromate films. Electrolytic treatment of goldplated silver in an electrolyte containing 40 g/l potassium chromate, 40 g/l potassium carbonate at pH 8.8 at a cathodic current density of 2.5 A/dm2'for 1-3 minutes significantly improves the tarnish resistance as revealed by the accelerated stain proofing tes

Chemical polishing of nickel-silver ornaments

A bath composition has been selected for descaling and chemical polishmg of n~ckel-s~lver artcles and the effect of each constituent of the bath on its polishing abllity has been studie

A Modified process for iridium electrodeposition

As a noble metal, Iridium finds many applications in the industry. Electrodeposited iridium, as a thin coating, provides a cheaper method of using the metal wherever possible. Iridium and platinum-iridium alloy are used in industrial water electrolysis as anodes because of their low oxygen overpotential. Of all the baths available for electrodepositing iridium, the bromide electrolyte appears to be the best. Different method of preparing the bromide electrolyte are compared: the one prepared using iridium chloride gives improved performance with respect to stability, current efficiency, higher deposit thickness, and appearance of the deposits, besides its cost effectivenes

Electrochemical preparation of Tin fluoborate for Tin plating

Tin plating is finding increasing importance in electronic, canning and automobile industries. The sulphate and chloride formulations have many limitations. Fluoborate bath is more favourable because of its high solubility, case of deposition etc. However, the preparation of tin fluoborate is still carried out by a time consuming chemical process which yields product containing impurities much higher than the recommended standards. An electrochemical method described in this paper offers a simple, easier and quicker method for the preparation of Sn(BF4)2 with negligible impurity levels, thereby quality electrodeposits can be obtaine