为了预测振动发电机的响应规律,采用弹簧-质量-阻尼构建系统模型,并结合电磁感应定律,分析输入振动位移与系统响应的耦合规律。磁场分布和磁力采用有限元法计算,在机电耦合仿真过程中将磁力采用三次多项式拟合,确定系数可达0.9976。正弦振动激励下的计算结果表明,由于磁力的非线性,动子位移和输出电动势出现了明显的谐波。在振幅和频率分别为5 mm和10 Hz的正弦振动激励下对样机进行测试,输出电动势的峰峰值和有效值分别为3 V和0.7 V。实验结果与仿真结果规律一致。
The system model was constructed used the spring-mass-damper structure in order to predict the response regularity of the vibration generator. The coupling rule about the input vibration and system responses can be analyzed based on the system model and faraday's law. Magnetic field distribution and magnetic force were calculated by the finite element method. Magnetic force is fit by cubic polynomial for the electromechanical coupling analysis, and coefficient of determination is up to 0. 9976. Simulation results show that the mover's displacement and output EMF have obvious harmonic due to the nonlinear magnetic force. A prototype was tested under the sinusoidal vibration with amplitude 5 mm and frequency 10 Hz. The peak-to-peak value and the effective value of output EMF are 3 V and 0. 7 V, respectively. The experimental results are consistent with the simulation results.