A Low-Cost Modular Optical Voltage Sensor for Power Transmission Applications

Because investment in the United States power-grid infrastructure has not kept pace with increased energy demands, existing power lines must operate close to conservative safety limits. Advanced instrumentation can simultaneously improve efficiency and maintain reliability by enabling true dynamic rating, identifying grid operational instability, and improving operator response to contingencies. Next generation voltage sensors must be low-cost to allow widespread deployment while providing critical power-line measurements to utility operators in real-time. This project will develop a modular, low cost optical voltage sensor that can be readily scaled for deployment on power lines over the full range of distribution and transmission voltages. The structure is comprised of modular sections surrounding an optical sensor core. The modular sections will have high-volume-production capability by taking advantage of advanced manufacturing techniques, which will dramatically reduce cost compared to conventional equipment. Phase I will address the design of the optical sensor structure, optical-to-electronic interface, and mechanical and dielectric form of the modular impedance block. The dielectric and mechanical designs for the sensor structure will be optimized using finite element modeling. Standard analog and digital interfaces for other substation equipment will be selected. A bench-top, proof-of-concept, optical voltage sensor will be fabricated for verification testing. Commercial Applications and Other Benefits as described by the awardee: The low-cost, optical voltage sensor should have a wide range of possible applications for the electric utility industry. The sensor should provide high bandwidth and highly accurate measurements in an environmentally friendly, reliable package. The sensor¿s modular structure should provide affordable voltage monitoring at all transmission line voltages. The integrated, self-powered capability should allow a wide variety of optical or conventional current sensors to be supported by the voltage sensor structure, with minimal additional cost or engineering. The high-dielectric-constant composite material could be used to improve the performance of conventional equipment, including surge arrestors, power transformers, and suspension or post insulators.