POWER SYSTEM LOSS MINIMISATION

1. POWER SYSTEM LOSS MINIMISATION GUIDED BY PROF.B.K.RANA Presented By:- Arun Kumar Samal 7th Semester Electrical Engineering Roll-No:0401101174

2. INTRODUCTION • Importance Of Electricity • Facts about Electricity • Electricity Losses • Problems In Loss Reduction • Useful Solutions • Conclusion • Queries

3. SOURCES OF LOSSES • Ignorance • Uncertainty • Upgradation of Human Resources • Poor Tarrif Structure • Indiscipline:ABT • Technical :Joints ,Neutral Conductor Size ,Length Of the Line • Energy Audit • Energy Management • Energy Forecast

4. FACTS ABOUT ELECTRICITY • Electrical Power cannot be stored to a large extent. • The demand of power varies throughout the day and cannot be predicted accurately. • Electrical Power is the optimal choice of energy as it can be transmitted efficiently and can be converted into other forms as required. • Electricity follows the path of least resistance.

5. Technical Losses Transformer and Transmission line losses due to poor maintainance. Unbalance loading Losses due to overloading and low voltage. Losses due to poor standard of equipments. Low power factor at off-peak hours. Harmonic distortion. Improper Earthing at consumer end. Long transmission lines. ELECTRICITY LOSSES

6. Major Transmission losses • Losses due to the phenomena of corona. • Copper losses in conductors. • Skin effect. • Proximity effect.

7. CORONA • The phenomenon of violet glow,hissing noise and production of ozone gas in an overhead transmission line is known as corona. • Factors affecting corona :- atmosphere :- conductor size :- spacing between conductors :- line voltage

8. CORONA… • Methods of reducing corona :-Increasing size of the conductor i.e by increasing the size of the conductor the voltage at which corona occurs is raised and hence corona effects are considerably reduced.This is one of the reasons why ACSR conductors are used. :-By increasing conductor spacing i.e by increasing the spacing between the conductors the voltage at which corona occurs is raised and hence corona effects are eliminated.

9. COPPER LOSSES • What is it.. :-Copper loss is the term reffered to the energy which is dissipated by the resistance in the wire used to wind a coil in an electrical devices such as transformer,motors,generators and in transmission lines.copper losses occur due to the flow of currents in the conductors.Copper loss increases both due to the increase in current and the resistance of the conductor. • Reduction of copper loss :- Copper loss can be minimised by using conductors of large diametresinorder to reduce the resistance per unit length of the condutors. :- The conductivity of a transmission line can be enhanced by using multiple insulated conductors.Hollow conductors can also help reduce he cost of transmission.

10. SKIN EFFECT • An alternating current flowing through a conductor doesnot distribute uniformly but tends to concentrate near the surface of the conductor i.e in ac system no current flows through the core and entire current is concentrated at the surface region causing an increase in its ac resistance.This phenomenon is called skin effect. • It depends upon :- type of material :- frequency :- diameter of the conductor :- shape of the conductor • Skin effect increases with cross section,permiability and supply frequency • In practice stranded conducters are used for T&D lines and hollow conductors for solid busbars.

11. PROXIMITY EFFECT • The inductance and, therefore, the current distribution in a conductor is also affected by the presence of other conductors its vicnity.This effect is known as proximity effect. • It affects the current distribution and results in the resistance of the conductor and decrease of the self reactance. • It is more pronounced for large conductors,high proximity and close proximity. • Stranded conductors are used for reducing proximityeffect.

12. Losses… Commercial Losses • Tapping(Hooking) in LT lines. • Faulty energy metres\ unmetred supply. • Errors and delay in meter reading and billing. • Uneven revenue collection.

13. Problems in Loss Reduction • No energy audit. • No segregation of losses into technical and commercial losses. • Political issues. • Lack of regular patrolling for checking the theft and tempering of metering. • No transparency in metereading and billing. • Lack of adequate investment for system modernisation.

14. Useful Solutions • Renewable energy sources. • Distributed local generation. • Availablity Based Tariff. • Improved Power Quality. • Demand side management. • IT applications. • Benchmarking. • Employee & Consumer Training.

15. Renewable Energy Sources • The World is blessed with an abundance of renewable energy sources e.g sunlight,water and biomass. • Wind Super power: It can be considered as the largest renewable energy sources. • Eco-Friendly power:solar photovoltaic electricity can contribute significantly to reduction in greenhouse gas emissions from the thermal power plants.

16. Distributed Generation • The cost of laying transmission linesin rural areas cannot be recovered due to less return. • Low tariff in agriculture and domestic sector leave few resources to expand or maintain the quality of supply. • Distributed generation is very useful to supply power in rural and remote places where the long distribution lines result in high losses. • It can help to reduce congestion on the power lines and strengthen local area transmission and distribution network. • It reduces the liklihood and impact of large-scale power outages while smoothing output fluctuations from individual power systes. • The benefits of DG over T&D and its customers include risk management,line loss reduction and voltage stability support.

17. Availability Based Tariff(ABT) • It controls the frequency variations by penalty/reward mechanism for any deviations from the schedule. • It helps to reduce gap between supply and demand by scheduling of every 15 minutes block. • It takes care of merit order of dispatch :- Maximisation of generation during peak load hours and load curtailment equal to the deficit of generation. :- Backing down of generation to match the system load reduction during off-peak hours, keeping the merit order of dispatch in view. • It improves grid discipline and thereby reduce transmission losses.

18. Power Quality Problems • The quality of power at distribution level is very bad in India (voltage deviations are more than 25% and frequency deviations >5%). • Voltage stabilizers at consumer’s premises result in incremental losses and require additional capital cost. • Harmonics has not been focused though it also increases the loss and distorts the power factor.

19. Harmonics • In non-linear loads, the current is of complex waveform due to dynamic characteristics of the load. The component of the complex waveform can be described as superposition of waveforms, called harmonics, having frequencies from 0 to infinity. • For distribution systems which must handle a large percentage of non-linear loads, the percentage of harmonic currents can be very high. • switch-mode power supplies, PWM converters, voltage source converters, fluorescent lighting with electronic ballasting, computers are the major sources of harmonics current. • About 58% of all power used can have harmonic currents overloading transformers, capacitors and other components on the distribution system.

20. Harmonics… • The additional current will increase losses in wire, bus bars, transformers and power factor correction capacitors used in the distribution system. • The additional heating caused by each of the harmonic currents of high frequencies. • Harmonic current will cause voltage distortion and low power factor. • Due to harmonic current the use of line filters before a drive will add more losses to the electrical system and could create line ringing and large voltage transients.

21. Reduction of Harmonics • Preventive solutions :- Phase cancellation or harmonic control in power converters by line reactors or isolation transformers. :- Developing procedures and methods to control, reduce of eliminate harmonics in power system equipment • Remedial solutions :- Use of filters(passive & active filters) :- Circuit detuning which involves reconfiguration of feeders or relocation of capacitor banks to overcome resonance

22. Demand Side Management • Systematic utilization of energy • Maximizing efficiency • Balancing supply and demand at consumer level • Improve economic development • Involve environment friendly power and reduce energy bills • Energy conservation • Energy audit

23. DSM by consumer training • Consumer can be trained for :- Shifting of energy use to off-peak hours :- Energy conservation :- Efficient choice and utilization of electric appliances :- Standards, quality and performance evaluation of domestic electric equipments :- Energy audit

24. IT Applications • Integrated inventory and billing system • Customers profiling • Data mining • Load survey data and network analysis of HT systems • Geographical Information System (GIS) and Customer Relationship Management

25. Benchmarking • Benchmarking is a collaborative learning process among a group of companies to :- focus on specific operating practices, :- compare measures and results :- identify improved processes within their organizations • Benefits of Benchmarking :- Promoting competition :- Performance evaluation :- Coordinated tariff :- Improving power quality and productivity :- Maximizing efficiency

26. Employee Training • Employees training should be conducted on a regular basis to upgrade their knowledge • Survey of UP Discoms shows that there is a pressing need for training of employees at all level and in all fields of the electric distribution company. • Employees also have much interest in IT applications in power sector

27. Employee training…. • Employees can be taught for :- Overview of the electric system operations including engineering criticality and quality. :- Awareness of Reforms program- APDRP :- Simulation tools :- Energy audit :- Energy management system :- Management information system :- Finance and Accounts

28. Government Initiatives • Accelerated Power Development and Reform Programme (APDRP) :- Full metering, energy audit and MIS, control of theft. :- Increase in transformation capacity. :- Increase in HT/LT ratio. Systems analysis and reconfiguration. :- Reduction of technical losses

29. Initiatives by Delhi (BSES and NDPL) • Installation of electronic meters at sub-transmission and distribution level. • Replacement of faulty meters • Computing Aggregated technical and commercial (ATC) losses • Consumer indexing • Improving billing and payment mechanism • Introducing an LT less distribution system • Improving quality of power • Customer care centres • Training employees

30. THANK YOU*********

31. ANY QUERIES ???