power systems loss

CAPACITOR FUSING APPLICATION GUIDE RULES Basic points to consider in fusing a capacitor in electric system network 1) Purpose of fusing:                 a. to isolate faulted bank from system                 b. to protect against bursting                 c. to give indication                 d. to allow manual switching (fuse control)                 e. to isolate faulted capacitor from bank 2) Recommended rating:                                a. The continuous-current capability of the fuse should be at least 165 percent of the normal capacitor-bank (for delta and floating wye banks the factor may be reduced to 150 percent if necessary).                 b. The total clearing characteristics of the fuse link must be coordinated with the capacitor "case bursting" curves. 3)  Tests have shown that expulsion fuse links will not satisfactorily protect  against violent rupture where the fault current through the capacitor is greater than 5000 amperes. 4)  The c

FUSE APPLICATION GUIDE RULES Basic points to consider in installing fuses in electrical system network 1)  Cold load pickup -  after 15 minute outage,  200% for.5 seconds                                                                          140% for 5 seconds                                        after 4 hrs, all electric  300% for 5 minutes 2)  "Damage" curve - 75% of minimum melt 3)  Two expulsion fuses cannot be coordinated if the available fault current is great enough to indicate an interruption of less than .8 cycles. 4)  "T" - SLOW and "K" - FAST 5)  Current limiting fuses can be coordinated in the sub-cycle region. 6)  Capacitor protection: The fuse should be rated for 165% of the normal capacitor current.  The fuse should also clear within 300 seconds for the minimum short circuit current. If current exceeds the maximum case rupture point, a current limiting fuse must be used. Current limiting fuses should be used if a s

Authored by: Alicia Valero Masa, Jean-Claude Maun, Stefan Werben ABSTRACT High Impedance Fault (HIF) detection is increasingly a concern of distribution network protection engineers. Practical methods to deal with HIFs are in great demand in the USA, where HIFs are not detected by conventional protection devices. The lack of a globally accepted description of HIFs is a difficulty for HIF detection. In the effort to understand and explain HIFs, we have carried out a theoretical study, simulations, laboratory tests, and studied field recordings. To study the influence of factors affecting HIFs, we have developed an Alternative Transients Program (ATP) simulation model and designed laboratory tests. HIF field recordings provided by Iberdrola Distribución Eléctrica S.A.U. validate the findings. In this paper, we present a  HIF characterization to improve HIF detection. This accurate characterization of HIFs allows us to develop a pattern recognition method to detect HIFs.

ELECTRIC MOTOR BRAKING METHODS TUTORIALS What are the methods in stoppng/braking an electric motor? MECHANICAL BRAKING Mechanical braking with magnetic lifting is the technique most widely used for the braking of electric motors . At standstill brakes of this type provide a holding torque, and are therefore used where loss of braking in the event of power failure could be dangerous. However, in certain cases it may be necessary to lift the brake without starting the motor. This can be done by supplying the brake coil from a separate power source, or with a manual release device. The mechanical brakes used for electric motors are shoe, multiple-plate or disc brakes. ABB Motors brakes are disc brakes with asbestos-free brake pads or linings. During braking , the braking torque is constant with mechanical braking . At standstill the brake has a holding torque. On some brakes the braking torque can be reduced for softer deceleration. When the motor is started again, the holdin

PRODUCT REVIEW: RM-18 WATTHOUR PORTABLE METER TEST SYSTEM Review on RM-18: Product for ensuring kilowatt-hour meter accuracy Non-technical loss in an electric utility in the form of pilferage can be in many forms. Many ways of stealing electric power can be done in the current technology today. Direct tapping, installation of jumpers, and meter tampering are just a few of those methods used to pilfer energy. Among the methods mentioned, the most rampant method would be through tampering of meter. Likewise, meter tampering can also have number of methods in doing so; the most common would be adjusting the accuracy of the meter . As we all know, meter accuracy is very important not only to the utility but also to the consumer since this is the one responsible for reflecting the actual consumption of the user. Unfortunately, criminal minds use this knowledge for their own benefit by opening the meter and adjusting its accuracy . Reports are usually given to the utility regarding a

Authored by: Ms.Priya S.Kamble and Ms.Sonali T.Bodkhe ABSTRACT This paper elucidates a current measurement method for wide range residual current measurement. The paper discusses Automated Meter Reading , a technology used to automate the task of reading consumption records of subscribers. The problem is first defined in terms of Utilities, critical infrastructure needs, revenue protection and operational efficiencies. Various drivers as well as impediments within such scopes are the defined. Moreover, different technologies proposed and implemented are discussed. The paper concludes by capturing the conclusions obtained and suggestions for further improvements of such technologies for future applications.

Authored by: S K DASSSR.MANAGER ENFORCEMENT NDPL. INTRODUCTION NDPL is the first one in India to implement AMR on such a large scale. We are having all HT CT meters and all LT CT meters being read with AMR . This technology is used by NDPL to streamline billing process and theft detection.