基于轮缸PV特性的电磁阀线性增压控制

电磁阀线性增压控制精度与电磁阀控制特性和轮缸PV特性有关,影响到制动能量回收系统中液压控制的响应精确性。本文提出了基于轮缸PV特性的电磁阀线性增压控制方法。分析了电磁阀的工作机理,并给出了电磁阀控制精度需求。通过对电磁阀控制机理分析,指出电磁阀线性控制具有一定的线性控制范围,且可通过增加线圈电流实现;通过对轮缸PV特性分析,指出轮缸具有低压非线性区和高压近线性区。试验分析不同电流变化率下的轮缸压力变化率特点,分别得到轮缸低压非线性区和高压近线性区内的线性增压控制算法。运用d SPACE平台搭建硬件在环试验台架,进行了不同增压速率下轮缸实际压力跟随目标压力的试验,结果表明本文提出的线性增压控制算法可以满足电磁阀控制精度需求,丰富了线性增压控制理论。

Linear Pressure Control of Solenoid Valve Based on PV Characteristics of Wheel Cylinder

The precision of linear pressure control of solenoid valve, which affects the response precision of hydraulic control in regenerative braking system, is related to the control characteristics of solenoid valve and PV characteristics of wheel cylinder. The control method of linear pressure control of solenoid valve based on PV characteristics of wheel cylinder was proposed. The working principle of the solenoid valve was analyzed, and the demand of control precision of the solenoid valve was given. By analyzing the control mechanism of the solenoid valve, it was pointed out that the linear pressure control of solenoid valve had a linear control range, and it can be also realized by increasing the coil current. By analyzing the PV characteristics of the wheel cylinder, it was pointed out that the wheel cylinder had nonlinear characteristics in low pressure region and approximate linear characteristics in high pressure region. The characteristics of the wheel cylinder pressure changing rate at different current changing rates were analyzed, and the linear pressure control algorithms of the low pressure region and the high pressure region were proposed respectively. dSPACE platform was used to build hardware-in-the-loop test bench, different pressure changing rates of wheel cylinder were tested, which can observe the following results between actual pressure and target pressure. The experimental results showed that the proposed linear pressure control algorithm can satisfy the requirement of the control precision of the solenoid valve, and enrich the linear pressure control theory.