Although the three-cylinder energy recovery device (TC-ERD) can simultaneously achieve the continuous flow of high and low pressure fluids, the change in resistance loss of the fluid channel during the stroke alternating will still cause flow fluctuation, which can be improved by optimizing overlap function. In this paper, the overlap function is optimized by adjusting the forward execution time (t₁) of switcher, and the high-pressure overlap can achieve “optimal-overlap” at t₁ = 0.5 s. Moreover, the flow fluctuations of high and low pressure fluids decrease as t₁ reduces. When t₁ decreases from 3 s to 0.5 s, the flow fluctuation rate of high-pressure fluid at design capacity (30 m³/h) is reduced from 9.17% to 3.43%, and that of low-pressure fluid decreases from 5.2% to 1.83%. Additionally, when the three hydraulic cylinders are alternately pressurized (depressurized), the difference in resistance loss of three high-pressure (low-pressure) fluid channels will also cause the flow fluctuation of high-pressure (low-pressure) fluid. After improving the resistance loss uniformity, the flow fluctuation rates of high and low pressure fluids are further reduced to 0.53% and 0.89%, and the flow fluctuation amplitudes of high and low pressure fluids are hardly affected by capacity within the range of 50.0%–133.0% of design capacity.

三缸能量回收装置（TC-ERD）虽然可以同时实现高低压流体的连续流动，但冲程交替过程中流体通道阻力损失的变化仍会引起流量波动，可通过优化重叠功能。本文通过调整切换器的前向执行时间（t ₁）优化重叠函数，高压重叠可以在t ₁  = 0.5 s时实现“最优重叠” 。而且，随着t _{1 的}减小，高低压流体的流量波动也减小。当 t ₁从 3 s 减小到 0.5 s 时，高压流体在设计容量（30 m ³/h)由9.17%降低至3.43%，低压流体由5.2%降低至1.83%。另外，当三个液压缸交替加压（降压）时，三个高压（低压）流体通道的阻力损失差异也会引起高压（低压）流体的流量波动。提高阻力损失均匀度后，高低压流体流量波动率进一步降低到0.53%和0.89%，高低压流体流量波动幅度在50.0%-50.0%范围内几乎不受容量影响。设计容量的 133.0%。