【作者】 来晓靓；

【导师】 冯培恩； 管成；

【作者基本信息】 浙江大学 ， 机械设计及理论， 2013， 博士

【摘要】 液压挖掘机作为国家建设发展中的重要工程机械,其节能减排具有重要的经济意义和环保意义。常规的元件技术革新,液压系统改进在挖掘机上已经趋于成熟,而混合动力技术的深入研究为挖掘机上的节能减排提供了新的突破口。目前,汽车上的油电混合动力应用研究较为广泛,并且有了较为成熟的产品；挖掘机上的油电混合动力呈现蓬勃发展的研究热潮。而油液混合动力技术的研究在挖掘机这一重要工程机械上还较为稀缺,研究院所和高校都还未有大量的研究文献出现,而在公司层面也只有几家国际大型公司对此项技术进行了研究和试制,并且多数实施保密措施。总体而言,挖掘机上油液混合动力技术还处于起步阶段,研究成果较少。本文以液压挖掘机上油液混合动力技术的应用为核心,结合液压挖掘机工作过程中特有的能量回收过程,在油液混合动力复合模式,模型建立,参数匹配,整机控制方法上进行了相应的研究,并建立相应的实验平台进行验证。以期为进一步的深入研究和产品化做出一定的贡献。本文的主要研究内容具体包含以下几方面：1.在普通液压挖掘机的结构、工况基础上,比较了串联式、并联式、混联式等油液混合动力方案的优劣,选取了适宜挖掘机的并联式方案作为本文的油液混合动力的研究结构。通过对该复合模式的结构设计,利用低成本的回转马达代替高成本的二次元件来实现油液混合动力的功能。2.设计了完全自动化的挖掘机势能和动能能量回收系统方案,并结合油液混合动力提出了压差补偿能量回收系统的原理和控制方法,克服了以往能量回收过程中较多的限制条件,提高了能量回收的能量利用率,减少了能量回收过程中的能量损失。3.提出了针对油液混合动力系统的参数匹配方法。以蓄能器为核心,克服并联式油液混合动力复合模式中能量密度较低的缺陷,满足挖掘机正常工作的动力需求。4.通过分析比较油电混合动力挖掘机上现有的控制策略,选用了适合于并联式油液混合动力系统的双转速工作点控制策略。在此基础上,提出变参数PID控制、负载预测以及发动机怠速切换相结合的方法来稳定单个工作点上的转速平稳,并通过遗传算法进一步提高整机的节能效果,获得了20%左右的燃油节省。5.设计和搭建了多功能的油液混合动力实验平台,对上述的控制方法进行了验证和分析,同时为今后的油液混合动力节能研究提供了评判标准。更多还原

【Abstract】 Hydraulic excavator was the very important construction machinery for the national economic development. Its energy saving, emission reduction had extraordinary economic and environmental significance. The innovation of conventional component technology and improvement of the excavator hydraulic system had been matured almost. But the in-depth research on hybrid technology offered a new breakthrough for the excavator energy saving. Currently, the research of the electrical hybrid was more widely on the vehicle and some mature product had been manufactured. On the excavator, the research of the electrical hybrid technology also was the most attractive. On the contrary, the research of the hydraulic hybrid technology was scarcity. There were few research literatures from institutes and universities. Only some large international excavator corporation had begun the study of hydraulic hybrid technology on the excavator and took an optimistic view about the prospects for its application. But their research information was kept confidentially. Overall, the research of the hydraulic hybrid technology was still in its infancy and had fewer achievements. In this thesis, in order to further in-depth research and make some contribution, we considered the application of the hydraulic hybrid technology on the excavator as the main task, combined the hybrid technology with the energy recovery during the excavator working as the dynamic energy recovery system, took research on the composite structure designing, system modeling, components parameter matching and machine control method, established the appropriate experimental platform for authentication.The main research areas in this thesis included the following aspects:1. Based on the general structure and working conditions of the hydraulic excavator, the series, parallel and the mixture type of the hydraulic hybrid system were compared, and the parallel type was selected as the main study structure. The low cost double rotary motor was used to replace the high cost secondary hydraulic component for realizing the hybrid function by redesigning the parallel structure.2. Fully automated solutions were designed for excavator potential energy and kinetic energy recovery. The solutions combined with the hydraulic hybrid system were called as the dynamic energy recovery system. And the principle and control method of this new system were explained. The new dynamic energy recovery system could overcome the restrictive conditions, improve the efficiency of the energy recovery course, and reduce the loss.3. A new parameters matching method for the hydraulic hybrid system was presented. The accumulator was taken as the core component during the matching course to overcome the disadvantage of the hydraulic hybrid technology which was in low energy density and meet the power demand of the excavator working conditions.4. By analyzing and comparing the existing control strategies, the double speed point control strategy which was suitable for the hydraulic hybrid system was chosen. On this basis, variable parameter PID control, load forecasting, and the engine idling switch methods were proposed to stabilize the single speed point steady. By genetic algorithm to further improve the overall energy savings, a20%fuel savings was gained.5. A parallel hydraulic hybrid test platform was designed and established to verify the control method mentioned above. And the platform also could provide the criterion for the future control method.更多还原