A Coordinated Electric System Interconnection Review—the utility’s deep-dive on technical and cost impacts of your project.

The transmission interconnection study included the following analyses:

Load flow analysis for steady-state conditions
Short circuit analysis for equipment stress validation
Transient stability study to evaluate dynamic behavior
Remedial Action Schemes (RAS) review
Fault duty analysis to assess equipment ratings

Industry-standard tools like PSSE and Aspen were used for system modeling. Simulations considered peak load conditions, multiple contingency events, and system-wide impacts of the proposed interconnection.

What is the goal of a System Impact Study (SIS)?
To determine whether a proposed interconnection can occur without negatively affecting the reliability of the bulk electric system.
What software tools were used in the study?
PSSE for dynamic and steady-state simulations; Aspen for protection coordination and fault analysis.
Did the study assess short-circuit impacts?
Yes, short-circuit current levels were analyzed and found within acceptable equipment ratings.
What was the interconnection voltage level?
230 kV, typical for large-scale energy injection projects.
Was transient stability maintained during faults?
Yes, all machines remained synchronized through various fault scenarios.
Did the project cause voltage violations?
No, voltage levels remained within planning criteria across the studied network.
Were any protection upgrades recommended?
Yes, refinements to relay settings and breaker failure logic were advised.
Did the study involve any Remedial Action Schemes?
The need for RAS was evaluated, but no new schemes were mandated.
How much generation capacity was modeled?
Up to 500 MW from the proposed facility.
Was compliance with NERC standards achieved?
Yes, all applicable NERC standards and regional reliability criteria were met.
Were additional lines or transformers needed?
No major network reinforcements were required.
Did the interconnection cause overloads under contingencies?
No, all elements operated within thermal limits for N-1 and N-2 events.
What is the importance of relay coordination in SIS?
To ensure timely fault isolation and prevent cascading outages.
Were voltage support devices required?
Potential installation of line reactors and capacitors was considered but not mandatory.
What were the load conditions modeled?
Summer peak load scenarios were used to simulate worst-case impacts.
Was dynamic response of the facility evaluated?
Yes, reactive power and frequency support capabilitis were verified.
How were SCADA systems addressed in the study?
Upgrades in data acquisition and remote monitoring were recommended for control coordination.
What’s the next step after an SIS?
A Facilities Study, which provides detailed engineering and cost estimation for required upgrades.
What if the SIS shows major impacts?
The interconnection may be delayed or redesigned to mitigate those impacts.
How long does a System Impact Study usually take?
Typically between 6 to 12 months depending on scope, complexity, and queue position.

In 1995, Sonny Patel earned his Electrical Engineering degree from the University of Illinois. But degrees don't build legacies — action does.

Utility. Generator. Regulator. Consultant. Few engineers have seen all four seats. Fewer still have sat in them.His experience spans nuclear, hydro, conventional generation, renewables, oil and gas, mining — and today's data centers, where he is authoring a three-book series on data center design. He is a Licensed Professional Engineer in six states and a Licensed Electrical Contractor in Florida (Unlimited EC) — he doesn't just design the work; he's qualified to stand behind its execution.Today, as Founder and CEO of Keentel Engineering, Sonny leads 51 engineers delivering substation design, power system studies, NERC compliance, and commissioning — done right, coast to coast.Three decades. Every side of the table. One standard: accountable engineering

In 1995, Sonny Patel earned his Electrical Engineering degree from the University of Illinois. But degrees don't build legacies — action does.

For three decades, he has worked the power industry from every side of the table: 16 years as a utility engineer at Exelon/Commonwealth Edison; generation leadership across hydroelectric, industrial steam turbine, and a 9 GW renewable fleet; NERC Regional Entity Senior Compliance Engineer and Audit Team Lead, auditing some of the nation's largest utilities; and testing and commissioning lead on equipment up to 765 kV — the very top of the North American grid.Utility. Generator. Regulator. Consultant. Few engineers have seen all four seats. Fewer still have sat in them.His experience spans nuclear, hydro, conventional generation, renewables, oil and gas, mining — and today's data centers, where he is authoring a three-book series on data center design. He is a Licensed Professional Engineer in six states and a Licensed Electrical Contractor in Florida (Unlimited EC) — he doesn't just design the work; he's qualified to stand behind its execution.Today, as Founder and CEO of Keentel Engineering, Sonny leads 51 engineers delivering substation design, power system studies, NERC compliance, and commissioning — done right, coast to coast.Three decades. Every side of the table. One standard: accountable engineering

12.47 kV pole-mounted distribution transformer assembly designed for U.S. IEEE and NESC utility stan

System Impact Study for Confidential 230 kV Transmission Interconnection﻿

Introduction

Purpose of the Study

Scope and Methodology

Key Technical Findings﻿

1. Steady-State Power Flow

2. Short Circuit Analysis

3. Transient Stability Assessment

4. Reactive Power and Voltage Support

5. Protection Coordination

Required Upgrades

Compliance and Reliability Standards

Conclusion

Frequently Asked Questions

What is the goal of a System Impact Study (SIS)?

What software tools were used in the study?

Did the study assess short-circuit impacts?

What was the interconnection voltage level?

Was transient stability maintained during faults?

Did the project cause voltage violations?

Were any protection upgrades recommended?

Did the study involve any Remedial Action Schemes?

How much generation capacity was modeled?

Was compliance with NERC standards achieved?

Were additional lines or transformers needed?

Did the interconnection cause overloads under contingencies?

What is the importance of relay coordination in SIS?

Were voltage support devices required?

What were the load conditions modeled?

Was dynamic response of the facility evaluated?

How were SCADA systems addressed in the study?

What’s the next step after an SIS?

What if the SIS shows major impacts?

How long does a System Impact Study usually take?

Services

Let's Discuss Your Project

About the Author:

Sandip "Sonny" R. Patel, P.E.

IEEE Senior Member · Founder & CEO, Keentel Engineering

Leave a Comment

Related Posts

Head Office

Austin Office

Sacramento Office

Baltimore Office

Place an image or any other element you want

System Impact Study for Confidential 230 kV Transmission Interconnection

Key Technical Findings