Ready for Transfer

Matrix Completion for Low-Observability Voltage Estimation

Dept. of Energy

Laboratory: National Renewable Energy Laboratory

Technology: Matrix Completion for Low-Observability Voltage Estimation

Opportunity: This technology is available as a prototype.

Details: Researchers at the National Renewable Energy Laboratory (NREL) have developed an innovation for estimating voltage phasors in power systems under low observability conditions. Traditional state estimation techniques require full observability (meaning the number of measurement points is not less than the number of buses); however, this is no longer realistic in today’s growing distribution systems. To estimate voltage phasors within a network, NREL’s system takes a matrix completion approach, which estimates unknown values in low rank matrices. The basic matrix completion technique is further augmented with power-flow constraints that provide an additional link between parameter values, thus improving the accuracy of estimation while requiring less data.


• Allowance for voltage estimation from whichever measurements are available
• An inclusion of power-flow constraints that allow for smaller amounts of required data for accurate estimation
• Both voltage magnitude and phase angle in systems can be determined with few voltage phasor measurements.

Applications: Potential commercial applications and industries for this technology include: grid voltage estimation, network optimization, and distributed generation.

Contact: For more information about this technology, contact Erin Beaumont at

To view the original technology listing on the Department of Energy’s Energy Innovation Portal, visit