Full-time high-precision measurement technology based on new integrated control-and-acquisition equipment: taking inverter performance testing in PV-storage systems as an example

Abstract With the global energy structure undergoes upgrading and transformation, the importance of photovoltaic storage (PV-storage) systems in building new power systems is becoming increasingly prominent. As the core power conversion component in PV-energy storage systems, achieving high-precision, real-time measurement of key parameters including output voltage, current, power, efficiency, and stability has become an urgent issue requiring resolution. This work proposes a novel integrated measurement and control method that combines control-acquisition functions. It designs a testing system that integrates control of the test object, experimental equipment, and high-precision data acquisition, processing, and storage. Using the performance testing of energy storage systems and photovoltaic (PV) inverters at two power stations in Chongming, Shanghai as examples, the testing achieved projects such as active power control for energy storage systems across all time periods, daytime reactive power regulation for PV inverters, and nighttime reactive power compensation. The voltage and current sampling accuracy is 0.0026% and 0.035% respectively, significantly exceeding the Class A accuracy requirements specified in the IEC 61000-4-30 standard: ±0.1% for voltage amplitude and ±1% for current. The integrated control-and-acquisition measurement system designed in this work employs full-time high-precision measurement technology to rapidly and efficiently fulfill customized testing requirements for PV-storage systems. Compared to traditional testing equipment, it reduces testing costs by 90% while weighing only one-fifth as much, offering superior economic efficiency, portability, and scalability. This innovation expands new application scenarios for PV-storage performance testing.