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Advanced Inverter Project (AIP)

Agenda

1. Project Overview2. Key Findings3. SRP’s Conclusion

AIP Results & Findings | Rotator Event | May 2019 2

Voltage CharacteristicsVo

ltage

126V

114V

Distance from Substation

• Project began in 2015 in partnership between EPRI and SRP • Enable customers to adopt DER while preserving grid

integrity • Assess integration opportunity & requirements

• Advanced inverter settings • Utility communications & control • Interconnection standards • Understand the role of Distribution Management System (DMS)

Study Overview & Objectives

AIP Project Description and Customer Participation

Component 1 – Autonomous “Set and Forget”• 400 advanced inverters • Deployed throughout SRP service territory

Component 2 – Limited/Seasonal Communication• 254 advanced inverters • Deployed throughout SRP service territory

Component 3 – Full Communication and Control• 121 advanced inverters • 1 Commercial PV system• Traditional voltage equipment

mini-DMS

New Equipment for Component 3

DMS

Line Capacitor Control

4g LTE modem

4g LTE modem

Communication box

Advance inverter

Capacitor Controller

Residential Installation

Component 3 Feeder - Quail 125

• Feeder extended to 8 miles• SRP Pinal Customer Center

- 180kW commercial site

• Encanterra ~100% solar• Communication

- SRP telecom network (fiber, FAN) - Verizon

9AIP Results & Findings | Rotator Event | May 2019

Component 3 Scenarios

AIP Results & Findings | Rotator Event | May 2019 8

• Recruit and install 750 new inverters• Install 380 communication systems • Challenging installations • Multiple home visits – customer inconvenience

Recruitments and Installations Challenges

© 2019 Electric Power Research Institute, Inc. All rights reserved.w w w . e p r i . c o m11

Advanced Inverters in Autonomous Mode

Advanced inverters followed settings accurately

Improved voltage control and increased hosting capacity on certain feeders

Greatest benefit from unique feeder and location specific settings

No observed impact on PV generation due to reactive power functions

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DMS Control Improved Voltage Management

Value of controlling advanced inverters increases as inverter size increases

LTCs and capacitor banks offer most value for controlling voltage today

ANSI A Range

Optimal voltage management observed from control of grid assets & large inverters

The DMS improved coordination and reduced customer voltage violations

Test Day: May 20th, Baseline Day: May 27th

© 2019 Electric Power Research Institute, Inc. All rights reserved.w w w . e p r i . c o m13

DMS Control Improved Voltage Management

Optimal voltage management observed from control of grid assets & large inverters

Value of controlling advanced inverters increases as inverter size increases

LTCs and capacitor banks offer most value for controlling voltage today

The DMS improved coordination and reduced customer voltage violations

ANSI A Range

Controlling commercial inverters and traditional assets

Test Day: May 20th, Baseline Day: May 27th

© 2019 Electric Power Research Institute, Inc. All rights reserved.w w w . e p r i . c o m14

Water-damaged monitoring box

Leading Practices & Industry Maturity

Advanced control architectures are needed to efficiently control hundreds of devices

Feeder model precision and reliable communications are key to DMS operation

Interoperability and reduced customization are needed

Effective customer engagement, system commissioning, training and lab testing 

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Pinal Customer Center - Commercial PV Array

• Distribution hosting capacity provides time • DMS control of larger inverters & traditional voltage control

assets is optimal • Today: DMS control of residential PV provides minimal value • Our models and GIS (geographical information system) are

not prepared for a DMS

SRP’s Conclusions

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Pinal Customer Center - Commercial PV Array

• Update interconnection process and standards• Prepare foundational systems:

• System models• GIS

• Refine near-term voltage strategy• Establishing 2-way control• Substation & line capacitor coordination

• Pilot solar/storage on distribution system

SRP’s Path Forward