Development of DC Power Standard Source Based on Programmable Josephson Voltage Standard

To meet the growing demand for high-precision DC power measurement and calibration, this paper presents a quantum-based DC power standard developed with a “standard source” architecture. This system integrates a compact heliumfree dual-channel programmable Josephson voltage standard, a three-stage cascaded high-voltage amplifier with low common-mode rejection ratio error, a large-current transconductance amplifier based on DC current transformer, voltage/current ratio self-calibration device, and other essential components. The design principles and key performance metrics of these core components are thoroughly described. Test results indicate that the system achieves a combined uncertainty of 1.5 × 10<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">−6</sup> (<italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">k</i>=1) at DC 1000V and 120 A. When used with a time pulse counter, the system can also serves as a direct calibration reference for DC energy meters. Finally, this paper discusses potential future advancements in quantum-based standards for DC power calibration technology.