Zero-Flux Current Sensors: The Ideal Solution for Precision Measurement in AC/DC and DC/AC Energy Conversion Systems

Zero-flux current sensors, renowned for their ultra-high accuracy, wide bandwidth, low temperature drift, and exceptional linearity, are the perfect choice for precise current measurement in AC/DC and DC/AC energy conversion systems. These sensors provide critical data for system control, ensuring efficient energy transfer and reliability—particularly in grid-tied applications where they effectively suppress DC offset injection, reduce demands on isolation transformers, and lower overall system costs.

This case study involves a photovoltaic inverter grid-connected testing system, primarily designed to verify the performance of photovoltaic inverters when connected to the grid, encompassing aspects such as power quality, efficiency, response speed, and protection functions. Within this system, the accuracy of current measurement stands as one of the pivotal indicators for evaluating inverter performance. The system employs three zero-flux current sensors and three high-precision voltage sensors. The zero-flux current sensors boast an accuracy of 10ppm and a linearity of 2ppm, while the high-precision voltage sensors exhibit an accuracy of 0.05% and a linearity of 0.02%. This setup simultaneously facilitates precise measurement of high currents under rated operating conditions in photovoltaic grid-connected tests, as well as accurate measurement of low currents during islanding test conditions.