CAJ | 학술논문

车辆制动能量的回收利用有利于改善整车的经济性，而基于传统内燃机的气动-内燃混合动力技术有望实现制动能量的高效、低成本回收利用。以城市路况运行车辆为应用对象，基于传统四冲程发动机提出了3种发动机压缩空气再生制动能量回收方案。通过建立3种方案共同的理想热力学循环，以可回收气体的最大压力、单位排量每循环回收气体质量、循环性能系数(COP)和循环平均指示压力为评价指标，对制动循环进行了分析。结果表明：增大压缩比、减小排气管缓冲腔容积与排量比或者减小排气门开启提前角均可以提高回收气体的最大压力，在机械结构允许的条件下，应尽可能减小排气管缓冲腔的容积；在制动过程中，减小排气门开启提前角可获得较高的循环平均指示压力和气体回收质量；随着气罐背压的增加，控制排气门开启提前角由大变小，可获得最佳的制动循环性能；理论上，二冲程制动循环 COP 与四冲程制动循环相同，但二冲程制动循环气体回收质量流量和制动功率为四冲程制动的2倍。
차량제동능량적회수이용유리우개선정차적경제성，이기우전통내연궤적기동-내연혼합동력기술유망실현제동능량적고효、저성본회수이용。이성시로황운행차량위응용대상，기우전통사충정발동궤제출료3충발동궤압축공기재생제동능량회수방안。통과건립3충방안공동적이상열역학순배，이가회수기체적최대압력、단위배량매순배회수기체질량、순배성능계수(COP)화순배평균지시압력위평개지표，대제동순배진행료분석。결과표명：증대압축비、감소배기관완충강용적여배량비혹자감소배기문개계제전각균가이제고회수기체적최대압력，재궤계결구윤허적조건하，응진가능감소배기관완충강적용적；재제동과정중，감소배기문개계제전각가획득교고적순배평균지시압력화기체회수질량；수착기관배압적증가，공제배기문개계제전각유대변소，가획득최가적제동순배성능；이론상，이충정제동순배 COP 여사충정제동순배상동，단이충정제동순배기체회수질량류량화제동공솔위사충정제동적2배。
Braking energy regeneration is beneficial to the improvement of vehicle fuel economy. Among many re-generative braking approaches,air hybrid engine, which is based on conventional internal combustion engine, could realize braking energy recovery with high efficiency and low cost. Based on the conventional 4-stroke internal combustion engine,three engine compression regenerative braking approaches were proposed for air hybrid engines aiming to be applied to urban driving situations. The common ideal thermodynamic cycle was established,and the maximum regenerated air pressure,indicated mean effective pressure(IMEP),coefficient of performance(COP), and regenerated air mass per displacement were selected to analyze the cycle characteristics. The results show that higher compression ratio,smaller ratio of exhaust chamber to engine displacement or closer exhaust valve open-ing(EVO)angle before TDC(BTDC)could enhance the maximum regenerated air pressure. Considering the limitation of mechanical structure,the exhaust chamber volume should be designed as small as possible. During the process of regenerative braking,reducing the exhaust valve opening angle could obtain higher IMEP and larger compressed air quantity. With the increase of tank pressure,the EVO BTDC should be controlled from a big magnitude to a small one if the optimal COP is considered. 2-stroke regenerative braking has the same COP as 4-stroke case theoretically, while the regenerated air mass flow rate and the indicated power are twice as much as those of 4-stroke case.