Active rotor with trailing-edge flaps is an effective methodology for helicopter rotor vibration control. Continuous-time higher harmonic control (CTHHC) algorithm is widely used both in simulation and experiment to alleviate rotor vibratory loads. The vibration control performance and stability of the active rotor system are mainly dependent on the parameters of CTHHC controller. A parametric model of active rotor for active vibration control, including the plant model in the form of transfer function which is obtained based on data of hover test, is established, and the simulation is conducted using this model. Nichols chart is employed to analyze the stability and stability margin of the active rotor system. The time constant and phase characteristics of the system are tuned to extend the stability margin of the system without remarkable attenuation of the vibration control performance. The effect of parameter adjustment on system performance and stability is studied through this simulation analysis, and it will be instructive for tuning controller parameters in active rotor experiments.