Effect of Photovoltaic Penetration on Radial Distribution Network.pptx

Solar photovoltaic penetration to a local distribution network is one of the best ways to improve voltage profile
and meet the power demand of consumers without the requirement of building a new transmission network.
However, the penetration level should not be exceeded in order to prevent from serious power issues like
power outage, reverse power flow, voltage fluctuations and voltage unbalance. This paper presents a simple
method to obtain best location for PV penetration to improve voltage profile and reduce system loss without
affecting the power factor of the supply grid. The maximum value of product sum of probability density function
and voltage ratio of the distribution system with and without solar PV gives the best location for PV penetration.
The effect of PV penetration on the ETAP modelled IEEE-10 Bus system is initially studied and later on again
applied on 11kV Rajgadh Feeder of Anarmani distribution system, Jhapa, Nepal is analysed. The result shows,
at 20% and 40% penetration, voltage at minimum voltage bus can be improved from 0.74 pu to 0.86 pu and
0.9 pu with 52% and 76.4% loss saving respectively. According to finding, 40% PV penetration at bus number
30 gives best result for Rajgadh feeder. The use of inverter that offer both active and reactive power can solve
the problem of low power factor in the supply grid, also capacitor bank can aid in the improvement of reactive
power.

1. Effect of Photovoltaic Penetration o n Radial Distribution Network: A C ase Study of Rajgadh Feeder, Anarmani Distribution System, Jhapa, Nepal Tribhuvan University Institute of Engineering, Pulchowk campus 1 By: Sudarshan Pandey 075MSESP018 MSc. Engineering in Energy System Planning and Management A Presentation on

2. O utlines Needs of research Problem statement Objectives Literature Review Methodology Simulation module Calculations and result Conclusion 2

3. Need of Research Distributed Generation – DG (e.g.. PV) has been growing rapidly in power system due to their capacity for solving energy issues like deregulation in power system, to meet the power demand and shortage of transmission capacities . In Nepal there are lots of distribution system which suffer from large power loss, voltage variation and instability, and reliability issues. This type of problem can be solve by different techniques and method(Using DG) This type of research helps the electrical utility in distribution service improvement, distribution planning and distribution line expansion purpose. It helps the consumer for reliable power supply 3

4. Problem Statement Voltage sag and line loss is the serious problem in distribution system .The loss and voltage variation in distribution system are the main problem found in radial distribution system of Nepal Rajgadh 11 kV feeder in Jhapa is suffering from low voltage at its end, the end user of different bus are facing low voltage problem up to 170-180V for single phase DCS receives complain ,Load like electric motor don’t operate at low voltage 4

5. O bjectives The main aim of this research to study about the effect of PV penetration in radial distribution system with voltage and loss assessment for Rajgadh feeder, Jhapa, some of the specific objectives are 1. Voltage profile assessment in radial distribution network before and after PV penetration. 2 . Loss assessment in radial distribution network before and after PV penetration. 5

6. Literature Review 6

7. Literature Review 7

8. Literature Review 8

9. Methodology 9 Literature review and finding the research gap . Select IEEE 10 bus radial distribution system as test bus system. Collection of load and line data of Rajgadh feeder of Ghailadubba substation. Load flow analysis of both IEEE 10 and 37bus Rajgadh feeer using Electrical Transient Analyzer Programmer software. Study of voltage profile of system with and without PV system at different penetration level . Study of system loss and power factor of supply grid at different penetration level of solar photovoltaic. Finding the optimal placement of solar PV in Rajgadh feeder . Based on product sum of probability density function and voltage ratio . Result and discussion of each finding Figure 1: Methodology flowchart

10. Rajgadh feeder This is the 11KV feeder with 6/8MVA, 33/11KV power transformer at Ghailadubba distribution substation. All the thirty seven 11/0.4 KV distribution transformer are taken as load bus. The total load of the system is 2769.75KW and 1340.44KVAR. The line conductor used in this radial distribution network are rabbit and weasel. 10 Figure 2: single line diagram of Rajgadh feeder

11. Simulink Module : Rajgadh Feeder 11

12. Load and line data for Rajgadh feeder 12 This is the 11KV feeder with 6/8MVA, 33/11KV power transformer at Ghailadubba distribution substation. All the thirty seven 11/0.4 KV distribution transformer are taken as load bus. The total load of the system is 2769.75KW and 1340.44KVAR. The line conductor used in this radial distribution network are rabbit and weasel. Rajgadh feeder

13. Calculation and Results 13 maximum value of ΣVnPr represent best position for PV penetration at given penetration level probability density function Load is varied from 60% to 110 % Voltage ratio ∑VnPr  fro n=1 to 37 Where μ and σ are the calculated mean and standard deviation of assumed loads respectively. X is rated load for which probability density function is calculated Loss   Loss saving= ((loss with PV-Loss without PV)/Loss without PV ) *100% Vn = bus voltage with DG on/ Bus voltge with DG off

14. Effect of distance from substation for PV penetration Comparative study of voltage profile and loss saving at different distance from substation (near to substation bus 4, mid of network-bus 20, end of network bus 37) better voltage profile and maximum saving around 28%occur for pv placement at end of network for 10% penetration . 14

15. Effect of distance from substation 15

16. Effect of penetration level Comparative study of voltage profile at different penetration level-10%, 20% and 30% at end of the network. on increasing the penetration level, the lowest voltage at bus no 37 is improved from o.74pu to 0.9 PU (21% improvement). 16

17. Effect on power factor of grid when PV is inject at different penetration at unity pf Most grid connected PV inverters are only set up to inject power at unity power factor, meaning they only produce active power. In effect this reduces the power factor, as the grid is then supplying less active power, but the same amount of reactive power . From 10% to 50% penetration grid power factor reduces from 0.88 to 0.75 lag. 17

18. Effect of PV penetration at different reactive power Penetration level 20% As the supply of reactive power is increased from 0 KVAR to 252.7 KVAR the power factor of the grid is increased from 0.86to 0.8932 lag. Power factor is increased by around 3.48 percent. On increasing KVAR from 0 to 252.7 KVAR. 18

19. Contd. There is slight improvement in voltage profile of network for increment of KVAR supply o to 252.7 KVAR There is KW loss saving of around 52% 19

20. Optimal placement for 20% penetration For 20% penetration better voltage profile with maximum loss saving occur when PV is inject at bus no. 35 Product sum also suggest bus no 35 for PV injection. With maximum loss saving of 46.1% The voltage of lowest voltage bus improved by 16.215% from 0.74Pu to .86Pu 20

21. Optimal placement for 40% penetration At 40% penetration bus no30 is found to be a best location for PV penetration with maximum loss saving of 76.4% with better voltage profile improvement . The voltage of bus no 37 ( lowest voltage bus) is improved from 0.744pu to 0.9pu. Optimal load sharing when PV is placed at bus 30. 21

22. Contd.. At 40% penetration with KVAR . We can make 76.4% saving in the system. 22

23. Result Validation Comparing the result with research done in thadi feeder of Lahan distribution network : the voltage of lowest voltage bus is improved from 0.55pu to o.91pu ( with DG sized varied from 1 to 40%). In Rajgadh feeder voltage of lowest votgae bus can be improved from 0.74 to 0.9 pu with 40% penetration of PV. A research done in Dodhara chadani feeder based on analytical approach shows about 83.6% loss saving can be made with installation of 787Kwp solar PV, which is 50% of peak load. Comparing the finding of research on Rajgah Feeder (76.4% loss saving at 40% penetration based) with, finding on research of dodhara chadani . It shows the finding obtained in this research work to be valid able 23

24. Conclusion Study shows the problem like voltage sag and line loss in radial distribution network can be solved using distributed generation like solar photovoltaic. Simulation result shows a significant improvement in voltage profile (21.75% for lowest voltage bus) from 0.74pu to 0.9pu with 40% penetration at bus 30. line loss saving of 76.4% can be made on radial distribution network of Rajgadh feeder compare to base case. The problem of low power factor of supply grid can be solved by using inverter that produce both active and reactive power, i.e. by injecting inverter at non- unity power factor. This helps to keep power factor of load and supply grid with in permissible limit. 24

25. References 25

26. Thank You 26