Detect the reference compensation current quickly and accurately is one of the most important elements for improving the compensation performance of distribution static synchronous (DSTATCOM). Traditional compensation current detection under the condition of asymmetric signals and distortion will introduce measurement errors. On the basis of summarizing existing compensation current detection methods, this paper proposed an improved current detection method without phase lock loop (PLL). The method to replace the phase lock loop through the calculation of three-phase positive sequence voltage, solve the problem of phase angle error introduced by PLL, and introduce the mean filter and feedback loop to reduce the delay. The simulation results verify the effectiveness of the improved detection method.