The Road to an IEEE-Certified Phasor Measurement Unit

By Robert J. Sawyer and Ravi Subramaniam

Phasor Measurement Units (PMUs) are seeing increased usage globally as a means to enhance the reliability of the power system. As the use of PMUs are expanding from a post-event forensics tool to more real-time wide area measurement and control, having a tested and certified PMU is becoming more critical. This article will provide more details to achieve IEEE certification.

In 2007 the Department of Energy (DOE), with support from the electric power industry and academia, formed the North American Synchrophasor Initiative (NASPI). The mission of the NASPI is to improve power system reliability and visibility through wide area measurement and control, by fostering the use and capabilities of synchrophasor technology.

A phasor is a complex number that represents the amplitude and phase angle of AC current and voltage; a synchrophasor is a UTC (Universal Coordinated Time) time-stamped phasor.

Through history we have learned that a reliable electric grid enhances our way of life and is critical for economic growth and national security. Many nations face issues with aging power infrastructure and other challenges with managing distributed energy resources (DER) and energy storage systems (ESS) with conventional power systems. Moreover, with rising concerns of cybersecurity and climate change, we urgently need a grid that is able to combat these new challenges.

Supervisory control and data acquisition (SCADA) systems are presently used to monitor and control the grid. Phasor Measurement units are 100 times faster than SCADA systems which allow operators to record and analyze grid conditions quicker with improved accuracy to maintain the reliability of the grid. These devices are time-synchronized which allow real- time operating conditions to improve grid reliability and efficiency.

In support of NASPI and various stakeholders, the IEEE Conformity Assessment Program (ICAP) developed a Synchrophasor Certification program to address an industry need that enables Phasor Measurement Unit (PMU) manufacturers to demonstrate conformance to IEEE C37.118-2005.

ICAP formed the Synchrophasor Conformity Assessment Steering Committee (SCASC) in 2012. The SCASC, made up of subject matter experts (SME) in the power industry with one of their common goals to accelerate the adoption of Synchrophasor technology through conformity assessment. This steering committee developed a conformity assessment program to demonstrate conformance to IEEE C37.118.1-2011 and IEEE C37.118.1a-2014 that specifies the essential procedures that can be used by test laboratories. These test procedures were developed by the SCASC members and are defined in the Synchrophasor Measurement Test Suite Specification (TSS). The TSS was developed and supported by SMEs representing national laboratories, utilities, equipment manufacturers and regional transmission organizations (RTOs).

Consumers Energy Laboratory Services (CELS)

CELS provides internal utility and commercial services in the areas of Calibration Services, Conformity Assessment, Metallurgical Services, Materials Testing, Regulatory Compliance Testing, Analytical Chemistry, Equipment Performance Testing and Nondestructive Testing. The laboratories quality assurance program meets the requirements of 10CFR50 Appendix B and ISO/IEC 17025 -2005 “General Requirements for the Competence of Testing and Calibrations Laboratories.


The IEEE Standards Association (IEEE-SA) is a global standardization body within the IEEE comprised of individual and corporate members and other contributing technologists, who develop consensus-based electro-technical, electronic, information and communication technology standards affecting a broad market base. The IEEE-SA provides a standards program that serves the global requirements of industry, government, and the public. The IEEE-SA is the only body that can speak for IEEE in the area of standardization.

In August of 2014 IEEE-SA and CELS signed a memorandum of understanding (MOU) with a common objective to perform and promote, directly or indirectly, regional and international standardization and conformity assessment initiatives. Subsequently, National Institute of Standards and Technology (NIST) successfully calibrated the PMU test system. IEEE-SA assessors successfully audited CELS for compliance to ISO 17025-2005 and the Test Suite Specification: IEEE Synchrophasor Measurement Test Suite Specification--Version 2. After the assessment CELS became the authorized test lab for PMU testing in April of 2015.

Since the development of the Synchrophasor Certification program, 2 PMUs have been successfully tested by CELS and certified by IEEE in accordance with IEEE Conformity Assessment Program policies. Manufacturers of PMU’s that meet the ICAP program policies are authorized to use the IEEE certified logo.

ICAP formed a Certification Registry and is the only authoritative listing of products certified in accordance with IEEE-SA Conformity Assessment Program policies and tested by the ICAP authorized test laboratory, in accordance with the related Test Suite Specifications. Products listed in this registry may utilize the IEEE certification mark which is globally recognized and accepted.


The certification program was developed to ensure PMUs are tested for compliance with IEEE C37.118.1-2011 and IEEE C37.118.1a™-2014. Utilities and end-users should require certified devices in their procurement process to ensure a high level of confidence that the procured PMU is compatible and will work in a large grid system. The certification program also provides manufacturers the opportunity to demonstrate continued compliance to the standard.

We hope you found this article beneficial and you can learn more about the IEEE Synchrophasor Certification program here.

For a downloadable copy of  November 2016 eNewsletter which includes this article, please visit the IEEE Smart Grid Resource Center.



r sawyer

Bob Sawyer is the department head of Calibration & Instrument Services, a division of Laboratory Services within Consumers Energy, one of the nation’s largest combination utilities. Bob started out as a calibration technician and has 35 years of experience in metrology with Consumers Energy. He is a voting member of the IEEE-SA Synchrophasor Conformity Assessment Steering Committee and an alternate voting member of the 174 standards writing group. He is a member of the 153 Utilities and 171 calibration system resources committees. His previous positions within NCSL International was the VP of the 1300 Central Division and the archive chair, leading a team developing plans for the 2011 NCSLI 50 year anniversary conference. He is currently leading a team to promote an Energy track for the annual NCSLI conference. His hobbies are traveling, golf, and touring the back roads of Michigan in his mustang convertible.


r subramaniam

Ravi Subramaniam is Technical Director of the IEEE-SA Conformity Assessment Program. In this role Ravi works closely with working groups on post standards implementation, which encompasses test plans, certification program development, and interoperability. Currently, he is focused on developing programs in interconnection of distributed energy resources, timing & synchronization in power systems, imaging and sensor technologies. He is secretary for the IEEE Synchrophasor Conformity Assessment Steering Committee (SCASC). Prior to taking on this role, Ravi has served in various technology management roles across the globe. He has previously worked for MET Laboratories, Inc., Honeywell and Ericsson. Ravi studied electrical engineering at Arizona State University and Johns Hopkins University.

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