Loading presentation...

Present Remotely

Send the link below via email or IM


Present to your audience

Start remote presentation

  • Invited audience members will follow you as you navigate and present
  • People invited to a presentation do not need a Prezi account
  • This link expires 10 minutes after you close the presentation
  • A maximum of 30 users can follow your presentation
  • Learn more about this feature in our knowledge base article

Do you really want to delete this prezi?

Neither you, nor the coeditors you shared it with will be able to recover it again.


Dispersed Generation in Distribution Networks

Expert Talk at a 2-day National Workshop on Renewable Energy in LE College Morbi on June 4-5, 2015

Kalpesh Joshi

on 6 April 2018

Comments (0)

Please log in to add your comment.

Report abuse

Transcript of Dispersed Generation in Distribution Networks

Dispersed Generation
Distribution Networks
Image curtsy: Forbes India, September 2012 Issue
Data source: S P Sukhatme, "Can India’s future needs of electricity be met by renewable energy sources? A revised assessment", Current Science, 103 (10), Nov. 2012
Research on Renewables at IIT GN
Forecasting of Generation - PV & Wind

Impact Investigation of small and large DGs on distribution network operations

Active and reactive power management in active distribution networks

Use of Battery Energy Storage System (BESS)

Energy management system for individual customers and at community level

Use Real Time Digital Simulation tools to model and simulate transient response of inverter based DGs during abnormal operating conditions
Active research areas
Generalized Model for PV Array
Single Diode Equivalent Model for PV Cell
Facilities for Photovoltaic Research
Continuously monitored PV Plants
10 kWp PV plant with Polycrystalline Modules
10 kWp PV plant with Thin-Film Modules
Cumulative capacity of 3 PV plants - 120kWp
Real Time Digital Simulator from Opal

FPGA based Quad-core system for studies related to transient stability, protection and control of distribution systems with DGs, electromagnetic transients and FACTS controllers

Interface with real world systems by 256 digital and 128 analog I/O ports
Source: J R Aguero, Smart Distribution Solutions for DER Integration, ISGT North America, Feb. 2015
Battery Energy Storage System
BESS - Improving Efficiency
Thanks for your attention!
Kalpesh Joshi
Proposing and Validating a Hypothesis
Generic solutions to case-specific issues may not yield best results
Some Generic Solutions proposed
Distribution Voltage Control Considering the Impact of PV Generation on Tap Changers and Autonomous Regulators - Y. P. Agalgaonkar, B. C. Pal, and R. A. Jabr
The Hypothesis
Influence of Distributed Generators (DGs) on steady state operations of unbalance distribution networks is highly case-specific
What is missed with SLE representation of
distribution networks?
Phase-wise unbalancing in loads - diurnal variations based on type of load (profiles)

Phase-wise geo-electric spread of the network - inherent unbalance in the network topology

Effect of unbalance on:
Voltage profile & TCOs of VR
Reactive support from shunt capacitors
Energy losses, power factor & maximum demand
Interaction of reactive support, real power injectione of DGs and VRs
What is already explored?
What is our contribution?
Size, Type & Location of DGs

Variability of demand & generation

Strategies for Voltage profile improvement

Strategies for energy loss minimization
The Test Networks
Feeder Voltage Profiles
Energy Losses & Energy Drawn
Results: IEEE 13 Node Test Feeder
Interaction of Capacitor and Voltage Regulator
Daily Load Profiles
Sequential Time Simulations (STS) Approach
Improved Low Voltage Grid-Integration of Photovoltaic Systems in Germany - T. Stetz, F. Marten, and M. Braun
Minimizing Energy Losses: Optimal Accommodation and Smart Operation of Renewable Distributed Generation - L. F. Ochoa, G. P. Harrison
Geo-electric spread & size of the network

Phase-wise reach to the load centres

Interactions between shunt capacitors & VRs

Power factor, maximum demand
IEEE 13 Node Test Feeder
Small area network, Dense load,
unbalance network topology
IEEE 34 Node Test Feeder
Big area network, Sparse loads,
Network topology - fairly balanced
Small Spot network, Fairly dense, cable-fed
It is the phase B which shows the opposite trend and its effect is dominant among the three phases leading to overall rise of TCOs due to inclusion of capacitors.

Additional capacitor in phase-B changes the overall response of VR

A single line equivalent network analysis will erroneously lead to a conclusion that capacitors may increase the number of TCOs and that the situation may become worse with increasing PV penetration.
Remarks on Capacitor - VR Interplay
Energy loss reduces noticeably with capacitors

A reverse trend observed in annual energy drawn in the presence of capacitors

A marginal increase in annual energy drawn is consistently observable with capacitors.

The ratio of energy loss to energy drawn remains almost constant at around 0.023 despite the fact that losses reduce with increasing PV penetration.
Results: IEEE 34 Node Network
Interaction of Capacitors & Voltage Regulators
VR-1 & VR-2 has predictable rise in number of TCOs in each phase with increasing PV penetration

Phase B and C in VR-1 respond with more TCOs in the presence of capacitors – collectively dominant over the reduction in phase-A’s TCOs

Exactly opposite trend – as compared to phase-wise trends in VR-1 – is exhibited by each phase in VR-2
Energy Loss & Energy Drawn
With increasing PV penetration, reduction in energy loss is expected.

Contradiction in this trend is observed in the energy loss results
Results: IITGN-VGEC Network
Effect on Power factor at source node
Effect on Daily Maximum Demand
Final Inferences
Aggregate energy losses exhibit opposing trends with increasing PV penetration in IEEE test feeders - due to network topology and load density

Size, phase and placement of capacitors need to be reconsidered - With DGs

Effect of capacitors vary widely with factors such as inherent phase-unbalancing in the network, load density and daily load profile

Single-phase equivalent analysis of unbalance networks for control of capacitors and VR switching may not succeed in equal measure with actual unbalance scenarios
Interaction of Capacitors & Voltage Regulators
Overall Appraoch for BESS Dispatch
To be presented at IEEE PES GM 2015, Denver, CO, USA, July 26-30.
Hypothetical BESS with 1 MW, 4 MWh rating considered in IEEE 37 node network for above exercise
BESS Project
Project objective: Analyze and improve BESS Performance
BESS rating: 1 MW, 3.2 MWh, Commissioned on April 2, 2015
Utility: Avista Corporation, WA, USA
Laboratories: Pacific Northwest National Lab. (PNNL, USA)
Schweitzer Engineering Lab., (Pullman, WA, USA)
University: Washington State University, Pullman, USA
Impact of PV Generation in Distribution Networks
Day-Ahead dispatch stratagy with Time-Series analysis

Exploiting phase-unbalancing as advantage in peak load shaving and load leveling

Improving reliability of supply
Full transcript