An electromechanical coupling model (EMCM) is constructed, and a contact-separation mode triboelectric nanogenerator (CS-TENG) is analyzed. In consideration of the contact-impact force between the moving and fixed electrodes, a piecewise linear differential equation of the moving electrode is derived and combined with the equivalent circuit differential equation to establish the EMCM of a CS-TENG with nonlinear variation of electrode distance. By using the harmonic balance method and arc length continuation technique, the dynamic output characteristics of the CS-TENG are obtained, and the stability of the results is determined. Both numerical integration and dynamic tests are employed to verify the accuracy of the present EMCM. The necessity of considering the nonlinear variation of the electrode distance in the EMCM is fully demonstrated through comparisons with the results of the existing model. Based on these results, the effects of the vibration excitation amplitude, contact stiffness, and structural damping on the output characteristics of the system are discussed. The present EMCM and output characteristics analysis can serve as a reference for the structural optimization of CS-TENGs and further promote their practical engineering applications.

构建了机电耦合模型（EMCM），并分析了接触分离模式摩擦纳米发电机（CS-TENG）。考虑到动电极和定电极之间的接触冲击力，推导了动电极的分段线性微分方程，并结合等效电路微分方程建立了电极距离非线性变化的CS-TENG的EMCM。利用谐波平衡法和弧长延续技术，获得了CS-TENG的动态输出特性，并确定了结果的稳定性。数值积分和动态测试都被用来验证当前 EMCM 的准确性。通过与现有模型的结果进行比较，充分证明了考虑 EMCM 中电极距离非线性变化的必要性。基于这些结果，讨论了振动激励幅度、接触刚度和结构阻尼对系统输出特性的影响。目前的EMCM和输出特性分析可为CS-TENG的结构优化提供参考，进一步促进其实际工程应用。