永磁线性涡流制动的性能分析与试验研究

Performance Analysis and Experimental Study of Permanent Magnet Linear Eddy-Current Brake

为弥补电磁涡流制动系统在重量和发热方面的不足,文中设计了一种永磁式线性涡流制动装置样机,基于等效磁路法推导制动力及吸力解析公式,并用于指导设计参数初始值的选取。通过有限元仿真,对比分析了永磁涡流制动与电磁涡流制动的制动力及吸力特性。搭建永磁涡流制动试验装置,测试不同速度、不同气隙的涡流制动特性,并与解析法及有限元法的计算结果进行对比和误差分析。结果表明:在与原电磁涡流制动装置长度相同的前提下,设计的永磁涡流制动装置样机可以达到与其相当的制动力水平,且在200~400 km/h区间永磁涡流制动力更稳定,吸力更低;解析计算和有限元仿真结果均与试验曲线变化趋势一致,有限元仿真精度更高;当气隙达到70 mm时,制动力和吸力均趋于0,此缓解高度与原电磁涡流制动装置的缓解高度一致。从制动力及吸力特性的角度分析,永磁线性涡流制动适合高速列车应用。

In order to make up for the limitations of electromagnetic linear eddy-current brake in terms of high weight and heat generation,a prototype of permanent magnet eddy-current brake is designed in this paper.The formulas of braking force and attractive force are deduced based on the equivalent magnetic circuit method,and they are used to guide the selection of initial values of design parameters.Through FEM simulation,the braking characteristics of permanent magnet and electromagnetic eddy-current brake are compared and analyzed.A test device is built to measure the braking characteristics at different speeds and various air gaps.Test results are compared with the analytical curves and FEM curves,and the error is analyzed.The results show that under the premise of the same length as the electromagnetic eddy-current brake,the braking force generated by permanent magnets is comparable with that of electromagnets.But when the train's speed is at the range of 200 km/h to 400 km/h,the permanent magnet eddy-current brake generates a more stable braking force and a lower attractive force.The test curves are consistent with the analytical results and the FEM results,and the FEM is more accurate than the analytical calculation.When the air gap reaches 70mm,both the braking force and the attractive force tend to be 0,and this release height is consistent with the value of the electromagnetic eddy-current brake.From the perspective of braking force and attractive force,the permanent magnet linear eddy-current brake is suitable for application in high-speed trains.