A lot of mechanical energy is lost in the braking process of automobiles, and it is feasible to harvest the energy and power electronic devices by using the technology of a triboelectric nanogenerator (TENG). In this study, we propose a pulsed freestanding TENG (PF-TENG) with a grid structure to harvest mechanical energy in the braking process, and use electric brushes to achieve a unidirectional pulsed output. We also design a passive power management circuit (P-PMC) to process and store the energy output. First, the general analytical solutions of the open-circuit voltage, short-circuit charge and output capacitance are derived from the theoretical model. According to the simulation results by using the finite element method, it is proved that the output energy of PF-TENG is independent of the grid number and proportional to the rotation speed. Second, the circuit simulation results demonstrate that P-PMC achieves impedance matching with the PF-TENG. The output power can maintain the maximum value under a wide load range and the optimal conversion efficiency is 94%. It is also found that the charging speed increases when the inductance value or the capacitance value decreases. In addition, a large pulse width makes the PF-TENG discharge completely. Finally, it is demonstrated that the PF-TENG can be used as a sensor to detect the wear depth of the brake pad with the open-circuit voltage.

在汽车的制动过程中损失了很多机械能，利用摩擦电纳米发电机（TENG）的技术来收集能源和电力电子设备是可行的。在这项研究中，我们提出了一种具有网格结构的脉冲独立式TENG（PF-TENG），以在制动过程中收集机械能，并使用电刷来实现单向脉冲输出。我们还设计了一个无源电源管理电路（P-PMC）来处理和存储能量输出。首先，从理论模型推导了开路电压，短路电荷和输出电容的一般解析解。根据有限元方法的仿真结果，证明了PF-TENG的输出能量与电网数无关，与转速成正比。其次，电路仿真结果表明，P-PMC与PF-TENG实现了阻抗匹配。在较宽的负载范围内，输出功率可保持最大值，最佳转换效率为94％。还发现，当电感值或电容值减小时，充电速度增加。另外，大的脉冲宽度使PF-TENG完全放电。最后，证明了PF-TENG可以用作传感器，以在开路电压下检测制动衬块的磨损深度。还发现，当电感值或电容值减小时，充电速度增加。另外，大的脉冲宽度使PF-TENG完全放电。最后，证明了PF-TENG可以用作传感器，以在开路电压下检测制动衬块的磨损深度。还发现，当电感值或电容值减小时，充电速度增加。另外，大的脉冲宽度使PF-TENG完全放电。最后，证明了PF-TENG可以用作传感器，以在开路电压下检测制动衬块的磨损深度。