Abstract:In the new power system, the rapid development of DC power distribution technology such as electric vehicle charging, photovoltaic, energy storage, etc., it put forward higher requirements for the accuracy of DC energy measurement. Aiming at the random time-varying dynamic characteristics of ripple components in DC signals, a new DC dynamic energy measurement method based on frequency adaptive multi-order quasi-synchronization algorithm was proposed. On the basis of finite impulse response filtering and differential zero crossing frequency monitoring, DC signals and ripple signals were tracked and separated, and then DC voltage, DC current, DC power, ripple voltage, ripple current, ripple power and other electrical parameters were calculated respectively to achieve precise measurement for DC energy with dynamic characteristics. In order to verify the accuracy and reliability of the algorithm, a DC dynamic energy measurement system was built. The test results showed that the accuracy of the algorithm was better than 0.01%, and it could be applied to the electric energy measurement under DC dynamic conditions.