“Novel Controls of PV Solar Farms in Night and Day for Benefit to Utilities”

Rajiv K. Varma, PhD, Senior Member IEEE

Professor

The University of Western Ontario

London, ON, Canada

Abstract:

PV solar farms are idle in the nights with their entire inverter capacity remaining unutilized. This seminar will present a set of novel patent-protected technologies for both nighttime and daytime control of PV solar farms as a dynamic reactive power compensator STATCOM, termed PV-STATCOM, for providing several benefits to both power transmission and distribution systems. These novel technologies on solar farms are 50-100 times lower in cost compared to conventional devices such as Flexible AC Transmission System (FACTS) used by electric utilities for providing the same functionalities in power systems.

The following night and day applications of the PV-STATCOM technology will be described:

1) Power Transfer Improvement in Transmission lines Through Increased Transient Stability and Enhanced Power Oscillation Damping

2) Mitigation of Subsynchronous Resonance in Synchronous Generators Connected to Series Compensated Lines

3) Increasing the Connectivity of Neighboring Wind Farms

4) Stabilizing Critical Induction Motor Loads

5) Decreasing Line Losses in Distribution Lines

6) Increasing the connectivity of PV Solar Farms

This PV-STATCOM technology leads to better network performance for utilities through 100% utilization of PV solar farms. It further opens up new revenue making opportunities for solar farms for providing various grid support functions during night and day.

This seminar will also present the nature and causes of series and parallel resonances in distribution/transmission networks. Harmonic amplification caused by these resonances can potentially result in maloperation or failures of utility/ customer owned equipment. Actual case studies will be presented of network and harmonic resonances, and their potential adverse impacts. It will be illustrated that harmonic resonances can constitute one of the major challenges in restricting the connectivity of inverter based renewable sources such as wind plants, PV solar plants and Plug-in Electric Vehicles.

Biosketch:

Dr. Rajiv Varma is currently a Professor and past Hydro One Research Chair in Power Systems Engineering in the Electrical and Computer Engineering Department at The University of Western Ontario (UWO), London, Ontario, Canada. Before joining Western in 2002, he was a Faculty Member at Indian Institute of Technology Kanpur (IITK), India, for 11 years. He is also an Adjunct Professor at University of Waterloo.

Dr. Varma has received thirteen teaching excellence awards at the University and Faculty levels at UWO. He is the principal co-author of the book “Thyristor-Based FACTS Controllers for Electrical Transmission Systems” published by IEEE Press and John Wiley & Sons in 2002. His research interests include Flexible AC Transmission Systems (FACTS), power systems stability, and grid integration of PV solar and wind power systems. He has led multi-university research projects funded by Ontario Centres of Excellence and several utilities totaling $8.2 Million in the development of pioneering technologies aimed at low-cost PV control strategies to improve grid voltages and stability. Dr. Varma has developed a new technology for “Nighttime Utilization of PV Solar Farms as STATCOM” for which six patents have been issued in US, Canada and China, and several other international patents are pending. For this research, he received the Prize Paper Award from IEEE Power and Energy Society (PES) in 2012 and the First Place Poster Award in 7^th International IRED Conference in 2016.

He led the first IEEE Tutorial on “Smart Inverters for Distributed Generators”; and co-delivered several Tutorials on “Static Var Compensator (SVC)” conducted by the IEEE Substations Committee. He is a Senior Member of IEEE. He is the Secretary of the IEEE PES “HVDC and FACTS Subcommittee”, and the Chair of IEEE Working Group on “HVDC and FACTS Bibliography“. He is also a Member of the IEEE P1547 Revision Working Group and Standard Technical Panel UL 1741. Dr. Varma obtained B.Tech. and Ph.D. degrees in Electrical Engineering from IIT Kanpur, India, in 1980 and 1988, respectively.