An MMC-DVR is a combination of dynamic voltage regulator (DVR) and modular multilevel converter (MMC). It can be used to solve the problem of dynamic voltage compensation for medium and high voltage. At present, linear control methods such as PID are basically used in MMC-DVR, but an MMC-DVR is a nonlinear system, so its control effect is not satisfactory. Therefore, a nonlinear Lyapunov control method for an MMC-DVR system under non ideal conditions is proposed. First, the mathematical model of an MMC-DVR is established. Then, the Lyapunov control systems of positive and negative sequence MMC-DVR under non-ideal conditions are designed. Finally, the correctness and effectiveness of the proposed Lyapunov control method for the MMC-DVR are verified by experiment. Compared with traditional PID control, the proposed Lyapunov control method can obtain good voltage compensation under ideal and non-ideal conditions, and the system has faster dynamic response and is more robust. This work is supported by the National Natural Science Foundation of China (No. 61905139).