Abstract This study analyzes electromagnetic power density Eā‹…j $\mathbf{E}\cdot \mathbf{j}$ in the ring current region using MMS data and multi‐point analysis method. For the first time, we statistically examine the large‐scale distribution characteristics of Eā‹…j $\left\langle \mathbf{E}\cdot \mathbf{j}\right\rangle $ (怈怉 $\langle \rangle $represents statistical results) within the magnetic equatorial plane, revealing a stably particles acceleration region Eā‹…j>0 $\left\langle \mathbf{E}\cdot \mathbf{j}\right\rangle > 0$ on the dawn side and a dynamo region Eā‹…j<0 $\left\langle \mathbf{E}\cdot \mathbf{j}\right\rangle < 0$ on the dusk side. Meanwhile, the corresponding distribution of current density and net charge density are also calculated. In the predawn sector near the acceleration region, a significant accumulation of net negative charges was observed. The dusk‐side dynamo region coincides with the net positive charge accumulation. The statistical analysis of electromagnetic power and net charge accumulation implies that the electrostatic field may play an important role in the energy variation of drifting particles, providing new insights into the evolution and dynamics of the ring current.

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