开关磁阻电机的发展与运用
开关磁阻电机的名字已经成为流行的任期本级电机。第一次提到这个词开关磁阻作了纳萨尔在一份文件中的电机工程师学会于1969年的法律程序。这个词开始流行从20世纪80年代起，经过长时间的努力，第一个商业剥削的技术，开关磁阻电机驱动器有限公司的机器或者称为可变磁阻电动机，这反映了起源的技术来自虚拟步进电机。即使这样，第一次认出不愿意机器建造了150多年前，最有名的戴维森作为牵引传动的电力机车在1838年。
Key Features Of SR Technology
Principle of Operation
The motor is doubly salient with phase coils mounted around diametrically opposite stator poles. Energisation of a phase will lead to the rotor moving into alignment with the stator poles, so minimising the reluctance of the magnetic path. This is the same principle of operation as the VR stepper motor. As a high performance variable speed drive, the motor's magnetics are optimised for closed-loop operation. Rotor position information is used to control phase energisation in an optimal way to achieve smooth, continuous torque and high efficency. The theoretical equations governing the torque production mechanism have been published countless times in the literature, so below is a simple graphical explanation. The current waveforms are superimposed on the angular unsaturated phase inductance. The maximum inductance corresponds to the minimum reluctance pole-aligned position. Positive torque is only produced at angles when the inductance gradient is positive.
主要特点简技术：
工作原理
电机双凸极相线圈安装在定子极截然相反。 Energisation一个阶段将导致转子迁入配合定子磁极，所以尽量不情愿的磁路。这是同样的原则运作的虚拟现实步进电机。作为一个高性能变速驱动器，电机的磁优化闭环作业。转子位置信息用于控制阶段energisation以最佳的方式来实现平稳，持续不断的扭矩和高效率。理论方程扭矩生产机制已出版了无数次的文学，所以下面是一个简单的图形解释。当前波形叠加的角度不饱和阶段电感。最大电感相当于最低极不情愿的不结盟立场。积极扭矩只有生产角度时，电感梯度是积极的。
At low speeds the phase current has to be constrained to protect the electronics because of the high available Volt-seconds. This is typically achieved by hysteresis current chopping as illustrated.
在低速阶段目前已受到限制，以保护电子设备，因为现有的高电压秒。这通常是所取得的滞环电流斩波所示。
At higher speeds the current is naturally constrained, and single-pulse voltage control is normally employed with angle advance prior to the unaligned position to optimise performance.
以更高速度目前自然是限制，而单脉冲电压控制通常采用的角度推进之前unaligned立场来优化性能。
The energy conversion mechanism is illustrated by the co-energy trajectory. The Wcon area represents the energy converted into mechanical energy (or converted from in the case of a generator). Wret is the surplus energy returned to the power supply rails. Minimising Wret by good magnetic design and optimal phase energisation control are the key features of an SR system.
Machine Topologies
SR machines can offer a wide variety of aspect ratios and salient pole topologies. This means that each application is likely to be better suited to a specific SR topology. Therefore it is difficult to give an overview of which topology offers what advantage or disadvantage without resorting to sweeping statements. However, here goes.
能源转换机制所显示的共同能源轨迹。代表的Wcon地区的能源转化为机械能（或转换的情况下发电机） 。 Wret是多余能量返回电源导轨。尽量减少Wret良好的磁性设计和优化阶段energisation控制的关键特征简系统。
机拓扑
简机可以提供各种各样的长宽比和凸极拓扑。这意味着，每个应用程序很可能是更适合于某一特定简拓扑。因此，很难给出一个概括的拓扑结构提供了哪些有利或不利的地位，而不诉诸全面报表。然而，这里不用。
Two-Phase Motor
Problems of starting compared with single phase machines can be overcome by stepping the air-gap, or providing asymmetry in the rotor poles. This machine may be of interest where the cost of winding connections is important, but again high torque ripple may be detrimental.
两相电机
存在的问题开始与单相的机器是可以克服的，加强了气隙，或者提供不对称转子磁极。这台机器可能会感兴趣的费用绕组连接是重要的，但再高转矩脉动可能是有害的
Four-Phase Motor
Maybe popular for reducing torque ripple further, but the large number of power devices and connections will probably limit four phase to a limited application field. Five- and six-phase motors can offer better torque ripple reduction compared with four-phase and three-phase.
Power Electronics
四相电机
也许流行的转矩脉动进一步减少，但大量的电力设备和连接可能会限制四个阶段在有限的应用领域。五和六相电机可以提供更好的转矩脉动相比减少四相和三相。
电力电子技术
Unipolar current in a conventional SR. (Can be driven bipolar especially if fully pitched wound where torque is produced by the change in mutual reluctance rather than self-reluctance). Single-ended converters can be used but the favourite is the two-transistor forward converter topology (asymmetric half-bridge) which has two power switches connected to either end of the power rails and in series with a winding for fluxing the machine and two diodes forming a return path. In the past there has been some debate about VA ratings when comparing other motor topologies but nowadays with modern majority carrier devices such as IGBTs, this argument is largely irrelevant especially when compromises are made with respect to torque ripple and acoustic noise. Similar rated drive electronics will more than likely have the same size devices. There is a cost disadvantage over a MOSFET inverter since the inherent MOSFET anti-parallel diode cannot be used.
单极目前在常规简。 （可驱动双极特别是如果在伤口完全投扭矩所产生的变化，而不是相互不愿意自我不愿意） 。单端转换器可用于但最喜欢的是双管正激变换器拓扑（不对称半桥） ，其中有两个电源开关，连接两端的电源轨以及一系列与绕组熔合机和两个二极管形成了返回的道路。在过去有一些争论弗吉尼亚评分比较其他汽车拓扑但现在与现代大多数运营商的设备，如IGBT的，这一论点基本上是不相关的特别是在妥协的方面所取得的转矩脉动和噪声。类似的评价驱动电子将超过可能具有相同的大小设备。有超过成本劣势的MOSFET逆变以来固有的MOSFET反平行二极管无法使用。
Commutation Control
Voltage or current control. Chopping or PWM. Depends on speed (available Volt-seconds) and any servo performance criteria. The control electronics will now be performed digitally and cost versus performance will be the main factor in selecting the most suitable circuit. ASICs have been mooted as the best option for very high volume drives, but microcontrollers, and more recently DSPs are proving to be the most popular control devices because of their flexibility. Current feedback is required for low speed operation and PWM is now finding favour because of acoustic noise issues. Rotor position feedback is required in some form and traditionally this is done with a rotor mounted sensor. This is a major cost and reliability issue and so a large amount of R&D effort has been placed in eliminating this sensor.
整流控制
电压或电流控制。切碎或PWM 。取决于速度（可用电压秒）和任何伺服性能标准。控制电子产品现在将进行数字化及成本的表现将是主要的因素，选择最合适的电路。专用集成电路已被认为是最好的选择非常高容量硬盘，但微控制器，以及最近的DSP都证明是最流行的控制设备，因为它们的灵活性。电流反馈需要低速运行和PWM现在找到赞成，因为噪音问题。转子位置反馈是需要以某种形式和传统这样做是与转子安装传感器。这是一个重大的成本和可靠性问题，使大量的R ＆ D的努力已放在消除这种传感器。
Major SR Issues
Rotor Position Sensing
As mentioned above, rotor-mounted position sensors are a liability. Not only do they introduce cost to the motor, but they can also be a major source of poor performance and unreliability. Work world-wide has now produced a number of viable schemes for sensorless operation. They all require monitoring of the phase current and applied voltage (flux observation), then by using knowledge of the magnetic characteristics, the rotor position is determined . This information is then used to optimise perfomance. It is interesting that the most often touted negative issues of SR performance may all be reduced by the merging of control means around real-time monitoring of the phase energisation in terms of flux-linkage and current coupled with knowledge of the machine being controlled (or possibly a self-learning control mechanism).
主要简问题
转子位置检测
如上所述，转子式位置传感器是一种责任。他们不仅引进成本的电机，但它们也可以成为主要来源，业绩不佳和不可靠。工作世界各地已产生了一些可行的计划，传感器作业。它们都需要监测的三相电流和电压（通量观测） ，然后用知识的磁特性，转子位置决心。此信息可用来优化性能。有趣的是，最经常吹嘘负面问题简性能均可减少合并控制手段周围实时监测的阶段energisation方面通量联系和目前加上知识的机器被控制（或可能是自学习控制机制） 。
Torque Ripple
SR machines have a significant torque ripple, especially when operated in single-pulse voltage control mode. This is the price to pay for high efficiency. For many applications where the machine is operating at fairly high speeds, this is not a problem since the mechanical time-constant is far longer than the fast rates of change of instantaneous torque produced by the motor. There are applications where the torque ripple is a major concern and a well publicised application by way of example here is automotive power assisted steering (EPAS). The human being can sense very low levels of torque purturbation and so minimising not only the peak-to-peak levels, but also angular rates of change are a high priority. Effort can be put into both the machine design and the control strategies to help. Optimising the individual phase torque-angle characteristic by salient pole shape profiling, longditudinal skewing of the rotor and angular phase current profiling can all help to minimise the inherent torque ripple. Significant work has already been carried-out by a number of institutions, noteably Arkon Unversity into ways of improving torque ripple performance. Judging by the number of patents filed by TRW Inc on a electric power assisted steering system utilising a variable reluctance machine, then healthy interest in using SR for torque ripple sensistive applications is still prevalent.
转矩脉动
简机器有重大转矩脉动，尤其是当经营单脉冲电压控制模式。这是要付出代价的，由于高效率。对许多应用在机器运行在相当高的速度，这不是一个问题，因为机械时间常数，也是远多于快速变动情况所产生的瞬时扭矩的发动机。目前应用的转矩脉动是一个重大关切和广泛宣传的方式应用的例子是汽车助力转向（经济合作协定） 。人类可以感觉到非常低的水平的扭矩purturbation和尽量减少不仅峰峰值水平，但还角的变动率是一个高度优先事项。努力可以投入的机械设计和控制策略提供帮助。优化个人相转矩角特性的凸极形状特征， longditudinal拉动转子和角相电流貌相都可以帮助，以尽量减少其固有的转矩脉动。重要的工作已经进行，由一些机构，尤其是爱肯大学到如何改善转矩脉动性能。从数量的专利申请由天合公司的电动助力转向系统利用一个可变磁阻电机，那么健康的兴趣使用简的转矩脉动sensistive应用仍然普遍存在。
