MOD-026-2 Compliance Services: Verification & Validation of Dynamic Models for Grid Reliability

A Complete Guide for Generator Owners, Developers, and Utilities (2026–2030 Compliance Roadmap)

Introduction: Why MOD-026-2 Is a Game-Changer for the Power Industry

The North American power grid is undergoing its most significant transformation in decades. The rapid integration of inverter-based resources (IBRs)—solar, wind, and battery energy storage systems—has exposed critical gaps in traditional power system modeling practices.

In response, NERC, under FERC Order No. 901, has introduced MOD-026-2 – Verification and Validation of Dynamic Models and Data, a new reliability standard that fundamentally changes how dynamic models are developed, validated, and maintained.

Unlike previous standards, MOD-026-2 is not just about submitting models—it is about proving that models accurately represent real-world system behavior under disturbances.



At Keentel Engineering, we provide end-to-end MOD-026-2 compliance services, helping Generator Owners, Transmission Owners, and Developers navigate this complex regulatory shift with confidence.

Key Compliance Timeline You Must Know

 MOD-026-2 introduces a phased compliance approach, but organizations that delay preparation risk major compliance gaps.

What Is MOD-026-2?

MOD-026-2 is a NERC Reliability Standard designed to:

• Ensure dynamic models accurately represent in-service equipment 
• Require verification of model parameters 
• Mandate validation using real-world disturbance data 
• Introduce EMT modeling requirements for IBRs, HVDC, and FACTS devices 

As defined in the standard, its purpose is to ensure models used in planning studies reflect actual system behavior for Bulk Electric System (BES) reliability 

Why MOD-026-2 Was Developed

Real Grid Events Exposed Major Issues

Industry disturbance events revealed that:

• Solar and wind plants were tripping unexpectedly 
• Models failed to capture control interactions and protection behavior 
• Positive sequence models could not simulate fast inverter dynamics 

These issues led to the development of MOD-026-2 as part of a broader initiative to improve grid reliability.

The Biggest Shift: From Model Submission → Model Accuracy

Under previous standards (MOD-026-1 and MOD-027-1):

• Entities submitted models
• Limited validation was required

Under MOD-026-2:

• Models must be verified against actual settings 
• Models must be validated using real disturbance data 
• Models must be continuously maintained 

This transforms compliance into a lifecycle process, not a one-time submission.

Key Requirements Explained (R1–R7 Simplified)

R1 – Model Requirements Definition

• Transmission Planner (TP) + Planning Coordinator (PC) define modeling standards 
• Includes: 

• Model formats 
• Software compatibility 
• Required functions

R2 – Positive Sequence Models

Generator Owners must provide:

• Dynamic models representing actual equipment 
• Parameter verification (settings match field) 
• Validation using:

• Voltage/reactive disturbances 
• Frequency/active power disturbances 

R3 – EMT Models (Critical for IBRs)

Applies to:

• Solar, wind, BESS 
• HVDC systems 
• FACTS devices 

Requires:

• High-fidelity EMT models 
• Validation using large disturbance events 
• Benchmarking vs positive sequence models 

This is one of the most technically demanding requirements.

R4 – Model Updates

• Required within 180 days after system changes 
• Includes: 

• Control changes 
• Firmware updates 
• Equipment modifications 

R5–R6 – Review & Response Cycle

• TP reviews models (within ~120 days) 
• Entities must respond: 

• Updated model OR 
• Technical justification 

R7 – Model Access



• TP must provide current models upon request 
  

EMT vs Positive Sequence Models (Why It Matters)

Positive Sequence Models (RMS)

• Used for planning studies 
• Limited in capturing:

• Fast inverter controls 
• Unbalanced faults 

EMT Models

• Capture: 

• Real control behavior 
• Protection logic 
• Sub-cycle dynamics 

MOD-026-2 requires EMT models because:

• RMS models cannot accurately simulate IBR behavior in weak grids 

EMT models are essential for large disturbance analysis

What Are “Large Signal Disturbances”?

These include:

• Transmission faults 
• Loss of generation 
• Switching events 
• Frequency excursions 

These events trigger:

• Control nonlinearities 
• Protection trips 
• Mode switching 

MOD-026-2 requires models to accurately replicate these events.

Continuous Compliance Lifecycle

MOD-026-2 introduces a long-term compliance cycle:

• Initial model submission 
• Validation using real events 
• Updates after changes 
• Revalidation every 10 years 

This creates ongoing compliance obligations not one-time work.

Who Must Comply?

• Generator Owners 
• Transmission Owners 
• Planning Coordinators 
• Transmission Planners 

Applies to:

• Synchronous generators 
• Solar, wind, BESS (IBRs) 
• HVDC systems 
• FACTS devices 
  

Industry Impact

Renewable Developers

• Must provide EMT models 
• Increased interconnection complexity 

Utilities

• Increased model review workload 
• Need for validation frameworks 

Generator Owners



• Ongoing compliance responsibility 
• Data collection & validation required 
  

How Keentel Engineering Supports MOD-026-2 Compliance

Keentel Engineering provides end-to-end compliance solutions, including:

Model Development

• PSSE / PSLF / PowerFactory models 
• EMT models (PSCAD, RTDS, HYPERSIM) 

Model Verification

• Parameter validation vs field settings 
• Control logic review 

Model Validation

• Disturbance-based validation 
• Event playback analysis 

EMT Benchmarking

• RMS vs EMT comparison 
• Large-signal testing 

Compliance Documentation

• Audit-ready reports 
• NERC evidence packages 

Ongoing Support

• Model updates (R4 compliance) 
• Periodic revalidation 
  

Why Choose Keentel Engineering?

• 30+ years of power system expertise 
• Deep experience with: 

• IBR modeling 
• NERC compliance 
• Grid interconnection studies 

• Expertise in: 

• PSSE + TSAT 
• PSCAD / EMT modeling 
• Dynamic model validation 
  

Get MOD-026-2 Compliance Support Today

MOD-026-2 is one of the most technically demanding NERC standards to date.

Don’t wait until deadlines approach.

Keentel Engineering can help you:

• Achieve compliance 
• Reduce risk 
• Ensure accurate modeling 

Contact us today to discuss your project.

 Frequently Asked Questions (MOD-026-2)