自由活塞内燃发电机稳态压缩比控制  

Stable Compression Ratio Control for Free-Piston Engine Generator

作　　者：许大涛[1] 左正兴[1] 冯慧华[1] 田春来[1] 

机构地区：[1]北京理工大学机械与车辆学院,北京100081

出　　处：《西安交通大学学报》2014年第5期56-60,88,共6页Journal of Xi'an Jiaotong University

基　　金：国家自然科学基金资助项目(51006010);高等学校学科创新引智计划资助项目(B12022)

摘　　要：为解决自由活塞内燃发电机的稳定控制问题,根据能量守恒定律建立了连续运行过程周期能量转化与传递模型。通过数值仿真分析,获得了满足稳定运行的基本能量平衡条件,包括压缩能和系统能量余值方程,从而实现了周期能量余值和压缩能的稳定变化。以压缩比为目标建立了连续周期能量动态平衡的控制系统及策略,即以喷油量和压缩比为控制输出变量,采用比例-积分-微分控制器进行控制,进而实现了可控压缩比的连续稳定运转。研究结果表明:采用所建控制系统及策略后,自由活塞内燃发电机运行可靠、稳定;压缩比在负载变化后出现短暂振荡,但经多个周期后恢复稳定,缸内峰值压力和运行频率具有相似的变化趋势,各参数变化均在可接受的范围内。To stably control free-piston engine generator, a model of energy conversation and transfer in continuous cycles was established. The essential energy balance conditions satisfying stable operation were constructed via numerical simulation, including the equation of the compression energy and system energy residual value, then the stability of cyclic energy residual value and compression energy were sequentially achieved. The control system and strategy for dynamic energy balance in continuous cycle were proposed, where the injection quantity and the compression ratio were taken as the control output variables, the proportion-integral-derivative controller was employed to drive the operation, and the continuously stable operation under the controllable compression ratio thus was realized. The results show that the free-piston engine generator operates reliably and stably under the control system and strategy. The compression ratio shortly oscillates once changing load, then gets back to the set value after undergoing several cycles. The peak pressure in-cylinder and operation frequency tend similarly and the parameters vary within the acceptable range.

关 键 词：自由活塞内燃发电机 控制策略 压缩比 数值仿真 

分 类 号：TK441[动力工程及工程热物理—动力机械及工程]