无刷直流电机驱动系统的可靠性研究

发布时间：2018-01-19 12:33

本文关键词： 无刷直流电机驱动系统可靠性 FMEA 故障树可靠性仿真　出处：《哈尔滨工业大学》2014年硕士论文　论文类型：学位论文

【摘要】：由于永磁材料以及大功率的电子器件的广泛应用，无刷直流永磁电动机得到了突飞猛进的发展，如今已被应用于农业、航天制造业以及生活的各个领域。同时带来的问题是整个电机驱动系统的工作环境越来越恶劣，不仅从室内移到室外，并且还要受到高温、雷电以及高压等环境因素的影响，这些全都会减小整个驱动系统处于工作状态时的可靠性。除此之外，无刷直流电机驱动系统本身就包含电阻、电容等一系列的电子元器件，而电子元器件的失效率受到各种各样因素的影响会变大，从而会使整个驱动系统的失效率减小，最终引起其可靠度的减小。因此，必须对整个驱动系统实施有关可靠性的分析研究。阐述了可靠性方面的一些概念和术语，包括了可用性、可靠性、故障率以及可靠寿命等，主要是为以后研究驱动系统的可靠性奠定基础。然后构建了其构成框图，根据建立的结构框图将整个驱动系统分为了两部分，先分别建立各部分的可靠性框图模型，从而构造出了整个系统的框图形式的模型，最终获得了其数学形式的模型。分析了电机驱动系统的各个模块，包括研究其各个模块的失效模式和失效机理，然后构建了各个模块的故障树；首先根据FMEA的研究方法确定出整个系统的失效模式，然后由FTA分析方法确定出整个系统的失效率高的部分，同时对整个系统实施定性的研究，从而得到了系统失效的主要的环节，，有利于接下来的失效率方面的计算。在建立的故障树的基础上，对系统的各个的元器件的失效率进行了分析，在这里采用的是元器件应力分析法，获得了驱动系统的每一个构成部分的失效率，并且由此得到了其他的特征量。根据各部分失效率所占的比例，分析出电机驱动系统易失效的部分，在进行设计时主要对这部分的失效率进行改善。接下来建立了电机驱动系统的可靠性的仿真模型，得到了可靠性指标的曲线，与理论计算得到的结果相符合，说明此仿真方法可信，并且可以用于其他方面的可靠性研究。最后采用了冗余设计以及降额设计来提高系统的可靠度。
[Abstract]:Because of the extensive application of permanent magnet materials and high-power electronic devices, brushless DC permanent magnet motor has been developed by leaps and bounds, and has been applied in agriculture. At the same time, the problem is that the working environment of the whole motor drive system is getting worse and worse, not only moving from indoor to outdoor, but also suffering from high temperature. Environmental factors, such as lightning and high voltage, all reduce the reliability of the whole drive system when it is in operation. In addition, the brushless DC motor drive system itself contains resistance. A series of electronic components such as capacitors, but the failure rate of electronic components will be affected by a variety of factors, which will reduce the failure rate of the whole drive system, and ultimately lead to the reduction of its reliability. The reliability analysis of the whole drive system must be carried out. Some concepts and terms of reliability are described, including availability, reliability, failure rate and reliability life. The main purpose is to lay a foundation for the later research on the reliability of the drive system. Then the structure block diagram is constructed and the whole drive system is divided into two parts according to the established structure block diagram. First, the reliability block diagram models of each part are established, and then the block diagram model of the whole system is constructed, and the mathematical model of the whole system is obtained. Every module of motor drive system is analyzed, including the failure mode and failure mechanism of each module, and then the fault tree of each module is constructed. First, the failure mode of the whole system is determined according to the research method of FMEA, then the high failure rate part of the whole system is determined by the FTA analysis method, and the qualitative research on the whole system is carried out at the same time. Thus, the main link of the system failure is obtained, which is beneficial to the calculation of the failure rate. Based on the established fault tree, the failure rate of each component of the system is analyzed, and the failure rate of each component of the drive system is obtained by using the component stress analysis method. According to the proportion of failure rate of each part, the failure part of motor drive system is analyzed. In the design, the failure rate of this part is mainly improved. Then, the simulation model of the reliability of motor drive system is established, and the curve of reliability index is obtained, which is consistent with the theoretical calculation results. It shows that the simulation method is reliable and can be used in other aspects of reliability research. Finally, redundant design and reduction design are used to improve the reliability of the system.
【学位授予单位】：哈尔滨工业大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TM33

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