NERC PRC-029-1 & PRC-024-4 Compliance for Inverter-Based & Synchronous Resources

With over three decades of utility-scale engineering expertise, Keentel Engineering helps Generator Owners (GOs) and Transmission Owners (TOs) stay ahead of the latest NERC Reliability Standards. As part of Project 2020-02, PRC-029-1 (ride-through performance for inverter-based resources) and PRC-024-4 (updated protection settings for synchronous generators and Type 1/2 wind) are now mandatory. These aren’t just regulatory checkboxes—they’re essential for ensuring your assets support grid stability during voltage and frequency disturbances on the Bulk Power System (BPS).

Why These Standards Matter

As inverter-based resources (IBRs)—including solar PV, wind farms, and battery energy storage systems (BESS)—and synchronous generators play an ever-larger role on the Bulk Power System (BPS), maintaining stability during voltage and frequency excursions is critical.

• PRC-029-1 establishes mandatory ride-through performance for IBRs, ensuring they stay connected and support voltage recovery during dips and swells.
• PRC-024-4 refines protection‐relay settings for synchronous machines (Type 1/2 wind, condensers, gas turbines), enhancing fault-clearing selectivity and coordination.
  
  

Meeting these standards goes beyond a regulatory checkbox—it prevents large-scale tripping events, upholds grid reliability, and keeps your generation assets compliant, resilient, and revenue-productive.

Our NERC Compliance Support

PRC-029-1: Ride-Through Performance for Inverter-Based Resources

• Engineering analysis & configuration to satisfy PRC-029-1 voltage and frequency ride-through curves.
• Attachment 1–3 verification for voltage, frequency, and transient-overvoltage requirements.
• Compliance documentation covering:
• Continuous Operating Region behavior
• Mandatory Operating Region performance
• Reactive-current prioritization
• No-trip zone adherence
• Legacy IBR exemption planning per FERC Order 901, including equipment-limitation justification and stakeholder notifications

PRC-024-4: Protection Settings for Synchronous Generators & Wind Resources

• Relay-setting validation & tuning for voltage- and frequency-based trips on synchronous machines (gas turbines, synchronous condensers) and Type 1/2 wind.
• Synchronous condenser integration, ensuring seamless coordination with upstream protection systems.
• Transition planning from PRC-024-3 to PRC-024-4 schemes, minimizing protection-gap risks during standards rollout.

Learn more about our full-spectrum Power System Studies to support your NERC compliance roadmap.

Compliance Deadlines & Keentel Engineering Services

Frequently Asked Questions — PRC-029-1 Ride-Through Requirements

Q1. What is PRC-029-1?

PRC-029-1 is a NERC Reliability Standard establishing mandatory ride-through performance for inverter-based resources (IBRs) during voltage and frequency disturbances on the Bulk Power System (BPS). Its goal is to keep solar, wind, BESS and hybrid plants online and supporting grid stability through fault events.

Q2. Who must comply with PRC-029-1?

• Generator Owners (GOs) of BPS-connected IBRs (solar PV, wind, battery storage, hybrids)
• Transmission Owners (TOs) owning dedicated IBR connections (e.g., VSC-HVDC links)

Q3. What are the defined ride-through voltage zones?

Measured at the high-side transformer:

• Continuous Operating Region: 0.9 – 1.1 pu
• Mandatory Operating Region: > 0.1 – < 0.9 pu and > 1.1 – ≤ 1.2 pu
• Permissive Operating Region: ≤ 0.1 pu
  
  

IBRs must remain connected and inject reactive current per their zone’s time-duration curves.

Q4. How must IBRs behave during disturbances?

• Stay connected unless disconnection prevents equipment damage
• Inject current to support voltage regulation
• Adhere to no-trip zones and restore active power rapidly once voltages normalize

Q5. What evidence is required for compliance?

Owners must retain for 5 years:

• Recorded disturbance/event data
• Ride-through performance validation reports
• Documentation of continuous vs. mandatory region behavior
• Exemption justification if equipment limits exist

Q6. Can legacy IBRs be exempted?

Yes—IBRs commissioned before PRC-029-1’s effective date may qualify for exemptions if documented hardware limitations prevent full compliance. Exemption requests must be communicated to the Planning Coordinator, Transmission Planner, and Reliability Coordinator.

Q7. When does PRC-029-1 take effect?

• Design-based Elements (R1–R3): Due 12 months after adoption for BPS IBRs
• Operation-based Elements: Upon installation of PRC-028-1 disturbance monitoring
• Frequency Performance (R4): Required by January 1, 2027 (or adoption date for non-BPS IBRs)

Q8. How can Keentel Engineering support my PRC-029-1 compliance?

We provide turnkey services:

• IBR modeling and ride-through curve validation
• Disturbance data collection, analysis & reporting
• Exemption planning and FERC-901 documentation
• Field testing, commissioning support, and five-year evidence packages

Partner with Keentel for NYISO TEI success

Partner with Keentel Engineering for a tailored PRC-029-1 and PRC-024-4 compliance roadmap—whether you’re a renewable developer or a utility.