1、开关磁阻电机的前景 一、开关磁阻电机发展简介 开关磁阻电机是 80 年代初随着电力电子、微电脑和控制技术的迅猛发展而发展起来的一种新型调速驱动系统,具有结构简单、运行可靠及效率高等突出特点,成为交流电机调速系统、直流电机调速系统和无刷直流电机调速系统的强有力的竞争者,引起各国学者和企业界的广泛关注。跨国电机公司 Emerson 电气公司还将开关磁阻电机视为其下世纪调速驱动系统的新的技术、经济增长点。目前开关磁阻电机已广泛或开始应用于工业、航空业和家用电器等各个领域。 1970 年,英国 Leeds 大学步进电机研究小 组首创一个开关磁阻电机( Switched Reluctance Motor
2、, SRM)雏形,这是关于开关磁阻电机最早的研究。 1972 年,进一步对带半导体开关的小功率电动机( 10w 1kw)进行了研究。到了 1975 年有了实质性的进展,并一直发展到可以为 50kw 的电瓶汽车提供装臵。 1980 年在英国成立了开关磁阻电机驱动装臵有限公司( SRD Ltd.),专门进行 SRD 系统的研究、开发和设计。 1983 年英国( SRD Ltd.)首先推出了 SRD 系列产品,该产品命名为 OULTON。 1984 年 TASC 驱动系统公司也推出了 他们的产品。另外 SRD Ltd. 研制了一种适用于有轨电车的驱动系统,到 1986 年已运行 500km。该产品的
3、出现,在电气传动界引起不小的反响。在很多性能指标上达到了出人意料的高水平,整个系统的综合性能价格指标达到或超过了工业中长期广泛应用的一些变速传动系统。 从上世纪 90 年代国际会议的上有关 SRD 系统的文章来看,对 SRD 系统的研究工作已经从论证它的优点、开发应用阶段进入到设计理论、优化设计研究阶段。对 SR 电机、控制器、功率变换器等的运行理论、优化设计、结构形式等方面进行了更加深入的研究。 二、原理简介及 优越性简介 开关磁阻电动机驱动系统( SRD)是较为复杂的机电一体化装臵, SRD 的运行需要在线实时检测的反馈量一般有转子位臵、速度及电流等,然后根据控制目标综合这些信息给出控制指
4、令,实现运行控制及保护等功能。转子位臵检测环节是 SRD 的重要组成部分,检测到的转子位臵信号是各相主开关器件正确进行逻辑切换的根据,也为速度控制环节提供了速度反馈信号。 开关磁阻电机具有再生的能力,系统效率高。对开关磁阻电机的理论研究和实践证明,该系统具有许多显著的优点: ( 1)电机结构简单、坚固,制造工艺简单,成本低,可工作于极 高转速;定子线圈嵌放容易,端部短而牢固,工作可靠,能适用于各种恶劣、高温甚至强振动环境。 ( 2)损耗主要产生在定子,电机易于冷却;转子无永磁体,可允许有较高的温升。 ( 3)转矩方向与电流方向无关,从而可最大限度简化功率变换器,降低系统成本。 ( 4)功率变换
5、器不会出现直通故障,可靠性高。 ( 5)起动转矩大,低速性能好,无感应电动机在起动时所出现的冲击电流现象。 ( 6)调速范围宽,控制灵活,易于实现各种特殊要求的转矩速度特性。 ( 7)在宽广的转速和功率范围内都具有高效率 ( 8)能四象限运行,具有 较强的再生制动能力。 ( 9)容错能力强。开关磁阻电机的容错体现在电机某一相损坏,电机照样可以运行。 与当前广泛应用的变频调速感应电动机相比,开关磁阻电机在成本、效率、调速性能、单位体积功率、可靠性、散热性等都具有明显的优势或竞争力。 如果说第一代开关磁阻电机( 1983 年研制)在小功率范围的效率比高效变频调速感应电动机低,第二代开关磁阻电机(
6、1988 年研制)的效率已全面超过了高效变频调速感应电动机。更难得的是,开关磁阻电机在宽广的速度和功率范围内都能保持较高的效率,这是变频调速感应电动机难以比拟的。感应 电动机要取得与直流电机相近的调速特性需采用复杂的矢量控制系统,而开关磁阻电机通过调整开通角、关断角、电压和电流,可以得到不同负载要求的机械特性,控制简单、灵活,能容易地实现软启动和四象限运行,而且由于这是一种纯逻辑的控制方式,很容易智能化,通过修改软件调整电机工作特性满足不同应用要求。 由于开关磁阻电机固有的转矩波动,可能导致较大的噪声和振动,事实上这种情况的发生往往与电机设计和控制的不合理相关,通过优化电机设计和控制策略,转矩
7、波动和噪声完全可以得到有效的抑制,正确认识到这一点对开关磁阻电机的开发和应用是 很重要的。 SRD Ltd.公司开发的伺服应用开关磁阻电机,转矩波动仅为 0.05%。近年研究的最优励磁控制策略、两次换流控制策略、电机噪声根源、定子振动模态、定子固有频率计算等成果对降低电机噪声都有积极的促进作用。随着设计和制造水平的提高,噪声必将进一步降低。 The prospect of Switched Reluctance Motor First, the development of Switched Reluctance Motor Introduction Switched Reluctance M
8、otor is the early 80s with the power electronics, micro-computer control technology and the rapid development and developed a new type of speed control drive system, with a simple structure, reliable and efficient operation of the prominent characteristics of higher has become AC motor speed control
9、 system , DC motor speed control system and the brushless DC motor speed control system of strong competitors, scholars and business caused by the extensive attention. Transnational Emerson Electric Co., Ltd. Electric Company will be regarded as one of the switched reluctance motor speed drive syste
10、m the next century, new technologies, economic growth. Switched reluctance motor current or the beginning has been widely applied in industry, aviation industry and household appliances and other fields. In 1970, the United Kingdom University of Leeds research team first stepper motor of a switched
11、reluctance motor (Switched Reluctance Motor, SRM) prototype, which is switched reluctance motor on the first study. In 1972, further semiconductor switches with low-power motor (10w 1kw) were studied. By 1975, substantial progress has been and has been the development of the battery for cars 50kw de
12、vice. In the United Kingdom in 1980 set up a Switched Reluctance Motor Drive Co., Ltd. (SRD Ltd.), Devoted to the SRD system research, development and design. In 1983 the United Kingdom (SRD Ltd.) First introduced the SRD Series products, the product named OULTON. TASC-driven system in 1984 also lau
13、nched their products. In addition SRD Ltd. Developed a tram driver for the system to run in 1986 has 500km. The emergence of electric drive in the sector caused the reaction. In many performance indicators reached an unexpected high level of performance throughout the system meet or exceed the price
14、 indices of industrial long-term a number of widely used variable-speed drive system. 90s from the last century of the International Conference on the SRD system, look at the article on the SRD system has its advantages from the demonstration, development and application of theory to the design stag
15、e, optimizing the design of a research stage. On the SR motor, controller, power converter, such as theory of operation, and optimize the design, structure and other aspects of the form of more in-depth research. Second, the principle of the superiority of a briefing and briefing Switched reluctance
16、 motor drive system (SRD) is a more complex integration of mechanical and electrical devices, SRD operational needs of online real-time feedback on the volume of a general rotor position, speed and current, etc., and then under the control objectives are given control of the information integrated c
17、ommand, to achieve operational control and protection functions. Rotor position detection is the SRD an important component of the rotor position detected signal is the right of the main switching device to switch to the logic of the basis for speed control provides a link speed feedback signal. Swi
18、tched Reluctance Motor has a regeneration capacity, systems and high efficiency. Switched Reluctance Motor for the theoretical study and practice has proved that the system has many significant advantages: (1) motor structure is simple, robust, simple manufacturing process, low cost, can work in a high speed; release easily embedded stator coils, the ends of short and strong, reliable, able to