Name: dc motors and generator action
Uploaded: 2023-04-30T06:43:07.000Z
Duration: 9 min 29 s
Channel: JoVE

K12 Standards

Arizona Science Standards

High School

Physical Science

HS.P3

HS.P3U2.7

DC Motors

1. 直流测试
<ol>
	<li>将低功率直流电源的电流限制为 0.8 A，将其端子连接至直流电机电枢。</li>
	<li>记录电源的直流电压和电流读数。</li>
	<li>估算每个绕组的电阻。</li>
	<li>依次对其他绕组（并励磁场和串励磁场）重复上述步骤。</li>
	<li>关闭并断开低功率直流电源。</li>
	<li>将内置励磁变阻器调至最大电阻，并测量其阻值。</li>
	<li>将外部串励磁场变阻器调至最大电阻，并测量其阻值。</li>
</ol>
2. 原动机设置与剩磁
本实验中的原动机是同步电机，其作为电动机运行，带动直流发电机的转子（电枢）旋转。
<ol>
	<li>确保三相断路开关、同步电机开关和直流电机开关均处于关闭状态。</li>
	<li>检查可变变压器（VARIAC）是否处于0%位置。</li>
	<li>将可变变压器连接至三相电源插座，并按照图5所示连接实验装置。</li>
	<li>检查“启动/运行”开关是否处于“启动”位置。</li>
	<li>打开三相断路开关。</li>
	<li>开启高压直流电源。</li>
	<li>确保所有接线均已远离电源接线端子。</li>
	<li>按下电源上的“V/I DIS”按钮以显示电压和电流工作点。调节电压旋钮至125 V。
	<ol>
		<li>切勿按下启动按钮。</li>
	</ol>
	</li>
	<li>按下直流电源面板上的“启动”按钮。</li>
	<li>缓慢增加可变变压器输出，直至VAC1读数为120 V。</li>
	<li>当同步电机达到稳态转速时，将“启动/运行”开关拨至“运行”位置。</li>
	<li>使用频闪仪测量并记录转速，同时记录VA。</li>
	<li>关闭直流电源，并将可变变压器调回0%。</li>
	<li>将“启动/运行”开关复位至“启动”位置。</li>
	<li>关闭三相断路开关。</li>
</ol>
<img alt="同步电机示意图，高压直流装置，可变变压器，测功机，机械联轴器。" src="/files/ftp_upload/10166/10166fig5.jpg" data-altupdatedat="1761830439000" data-alt="图5"> 
图5：原动机设置的示意图。 <a href="//cloudfront.jove.com/files/ftp_upload/10166/10166fig5large.jpg" target="_blank">请点击此处查看此图的放大版本。</a>
3. 直流并励发电机特性表征
<ol>
	<li>在直流发电机侧，将并励绕组与电枢绕组并联连接，如图6所示。</li>
	<li>使用内置变阻器作为 RFsh(ext)，并使用万用表作为电流表测量 IFsh。</li>
	<li>将“S1”保持断开状态，以进行空载试验。</li>
	<li>将“RFsh(ext)”调节至最大电阻值。</li>
	<li>合上三相断开开关。</li>
	<li>按下直流电源面板上的“启动”按钮。</li>
	<li>缓慢增加VARIAC输出，直至 VAC1 读数为120 V。</li>
	<li>当同步电机达到稳态转速时，将“启动/运行”开关拨至“运行”位置。</li>
	<li>使用其他部分所述的频闪灯技术测量轴转速。</li>
	<li>记录此时直流发电机侧空载状态下的 VA 值。</li>
	<li>减小 RFsh(ext)，直到 VA 处产生的电压约为150 V。</li>
	<li>此后，将“RFsh(ext)” 以五个近似相等的步长逐步减小，直至达到最小电阻值。
	<ol>
		<li>每一步均测量 VA 和 IFsh。</li>
	</ol>
	</li>
	<li>将 RFsh(ext) 保持在最小值。</li>
	<li>关闭直流电源。</li>
	<li>将VARIAC输出降至0%。</li>
	<li>将电流表从测量 IFsh 改为测量 IA。</li>
	<li>按前述步骤重新启动装置。</li>
	<li>将 RL 设为300 Ω，并闭合“S1”，测量 VA 和 IA。</li>
	<li>断开“S1”，将 RL 设为200 Ω，然后闭合“S1”，测量 VA 和 IA。</li>
	<li>断开“S1”，将 RL 设为100 Ω，然后闭合“S1”，测量 VA 和 IA。</li>
	<li>关闭直流电源，并将VARIAC输出设为0%。</li>
	<li>保持同步发电机侧的连接不变。</li>
	<li>断开直流发电机的连接。</li>
	<li>将“启动/运行”开关复位至“启动”位置。</li>
	<li>断开三相断开开关。</li>
</ol>
<img alt="带可变变压器、高压直流电源和测功机耦合装置的同步电机示意图。" src="/files/ftp_upload/10166/10166fig6.jpg" data-altupdatedat="1761830439000" data-alt="图6"> 
图6：并励直流发电机装置的示意图。 <a href="//cloudfront.jove.com/files/ftp_upload/10166/10166fig6large.jpg" target="_blank">请点击此处查看此图的放大版本。</a>
4. 直流串联发电机特性表征
<ol>
	<li>在直流发电机侧，将串励绕组与电枢绕组串联连接，如图7所示。
	<ol>
		<li>使用外部变阻器作为 RFse(ext)。</li>
		<li>使用内置变阻器作为 RL，并将其调至最大电阻值。</li>
		<li>将“S1”保持断开状态，以进行空载试验。</li>
		<li>将 RFse(ext) 保持在最大电阻值。</li>
	</ol>
	</li>
	<li>合上三相断路开关。</li>
	<li>按下直流电源控制面板上的“启动”按钮。</li>
	<li>缓慢增加VARIAC输出，直至 VAC1 读数为120 V。</li>
	<li>当同步电动机达到稳态转速后，将“启动/运行”开关拨至“运行”位置。
	<ol>
		<li>在直流发电机侧测量此空载状态下的 VA。</li>
	</ol>
	</li>
	<li>闭合“S1”，并根据需要减小 RFse(ext)，使 VA 出现非零读数。</li>
	<li>调节 RL，以接近相等的五个步长逐步减小，直至达到其50%设定值（即300 Ω），然后闭合“S1”，测量转速、VA 和 IA。
	<ol>
		<li>断开“S1”，将 RL 设为200 Ω，再闭合“S1”，测量转速、VA 和 IA。</li>
		<li>断开“S1”，将 RL 设为100 Ω，再闭合“S1”，测量转速、VA 和 IA。</li>
	</ol>
	</li>
	<li>关闭直流电源。
	<ol>
		<li>将VARIAC输出调至0%。</li>
		<li>保持同步发电机侧的接线不变。</li>
		<li>断开直流发电机的连接线。</li>
		<li>将“启动/运行”开关复位至“启动”位置。</li>
	</ol>
	</li>
	<li>断开三相断路开关。</li>
	<li>拆除所有导线和仪表。</li>
</ol>
<img alt="带有可变自耦变压器和测功机设置的同步电机示意图，用于机电转换。" src="/files/ftp_upload/10166/10166fig7.jpg" data-altupdatedat="1761830439000" data-alt="图7"> 
图7：串励直流发电机装置的示意图。 <a href="//cloudfront.jove.com/files/ftp_upload/10166/10166fig7large.jpg" target="_blank"> 请点击此处查看此图的放大版本。</a>
&lt;

在交流感应电机和同步电机发明之前，直流电机比现在常见得多。目前，它们仍广泛应用于一些简单的低功率场合，例如玩具、小型机器人和传统设备中。由于励磁结构更简单，采用丰富非稀土磁体的永磁直流电机比并励和串励直流电机更为常见，尤其适用于低成本和低复杂度的应用场景。

直流电机

来源：Ali Bazzi，康涅狄格大学电气工程系，斯托尔斯，康涅狄格州。
直流电机使用直流电流和电压运行，而交流电机则需要交流电流和电压。直流电机是最早被发明的电机类型，其工作原理基于由直流电流控制的两个磁场。由于直流电机具有两个分别称为励磁绕组（field）和电枢（armature）的磁场，只要提供适当的励磁，同一台电机可方便地重新配置为电动机或发电机。励磁绕组通常位于定子侧，而电枢则位于转子侧（与交流电机的结构相反或内外颠倒）。励磁可通过永磁体或绕组（线圈）提供。当电流施加到电枢或转子线圈时，电流从直流电源通过静止的电刷和安装在旋转转子上的滑环传递至线圈，滑环与电刷保持接触。当转子电枢线圈中有电流通过而形成载流回路，并处于来自定子或励磁磁体的外部磁场中时，该回路会受到力的作用。由于该回路通过轴承固定在电机两侧，所受的力产生转矩，从而使转子轴旋转，而非向其他方向移动。
这种旋转使磁场对齐，但与此同时，电刷上的滑环切换位置，即发生“换向”，这一过程被称为换向过程。当换向发生时，转子线圈中的电流方向反转，磁场再次相互排斥，从而在相同的旋转方向上产生持续的转矩。该过程不断持续，使转子轴旋转，实现电动机运转。在发电机运行中，外部提供机械旋转给转子轴，线圈在磁场中运动产生感应电流，电流随后从转子中输出。
本实验中讨论的电机采用励磁绕组而非永磁体。在直流电机运行中，换向过程至关重要，它通过滑环和电刷将能量从旋转的转子（电枢）传递到外部电路，因为转子在旋转，若直接使用旋转导线会导致导线缠绕并断裂。然而，这些电刷和滑环存在显著的可靠性问题，需要定期维护、更换电刷、清理，并可能产生火花。这些问题导致大多数直流电机已被不存在此类问题的交流电机所取代，而现存的直流电机大多采用永磁体励磁，例如用于玩具和简单的低功率工具中。一类被称为无刷直流电机（BLDC）的交流电机，利用直流电源和电力电子逆变器，将直流电转换为逆变器输出的交流电压。
本实验的目的是测试两种主要的直流电机配置：并励和串励。实验旨在估算电机中的剩磁，并研究不同配置下的空载和负载特性。

串联绕组通常承载高电流，其额定值等于电机的额定电枢电流，因为串联绕组与电枢绕组是串联连接的。因此，串联绕组的电阻值通常在毫欧（mΩ）至几欧姆（Ω）的量级。而并励绕组则应从电源中汲取最小的电流，该电源同时为电机的电枢供电，因此其电阻值较大，通常为几十到几百甚至几千欧姆（Ω）。
剩余磁通 λR 可通过测量空载时的电枢电压来估算。由于这是空载条件，反电动势与电枢电压相等，而反电动势（EA）是 λR 的函数，满足 EA=If λRωm，其中 If&#160; 为励磁电流，ωm 为机械转速。
<p class="jove_conten...

来源：Ali Bazzi，康涅狄格大学电气工程系，美国康涅狄格州斯托尔斯市  
直流电机以直流电流和电压运行，其工作原理基于……

直流电机用于驱动各种设备，从小型玩具和可充电电动工具，到电动汽车。这些机电装置由内部的导电线圈（称为电枢）和外部的磁体（称为定子）组成。直流电源通过换向器电刷向电枢提供电流，从而产生电磁力，使线圈旋转。电磁力的大小取决于磁场与线圈之间的夹角，导致旋转过程中转矩出现波动。电枢上均匀分布的多个绕组可减小转矩波动，并防止换向器造成电源短路。换向器电刷周期性地改变线圈中的电流方向，进一步避免磁场对齐。本视频将介绍直流电机的结构配置，并演示如何在不同负载条件下测量直流电机的性能参数，如转速、电流和电压。在直流电机中，永磁定子最为常见。然而，当定子磁场通过导体绕组产生时，可通过电场设计来调节电机的性能特性，例如转速和转矩输出。例如，转速与电机产生的电压相关，该电压称为电动势（EMF）。同样，转矩与电流成正比。这些特性随电机设计的不同而变化，并影响特定应用中所选用的电机类型。直流电机的四种基本电子结构分别为他励、并励、串励和复励。他励电机对励磁绕组和电枢使用独立的电源，从而实现对不同负载的独立控制。在并励结构（最常见的配置）中，励磁绕组与电枢负载并联，共用一个直流电源。这种结构可在负载变化时提供可调转速，适用于机床和离心泵等设备。在串励结构中，直流电源将励磁绕组与电枢串联供电，可提供较高的启动转矩，适用于克服列车、电梯或起重设备等机械的惯性负载。复励电机则同时采用并励和串励电路，兼具高启动转矩和良好的转速调节能力。并励绕组可连接在串励绕组之前或之后。在概述了直流电机的结构类型后，接下来将演示并励直流电机中电流、电压与负载关系的分析方法。直流测试中收集的数据可根据需要用于建立等效电路模型。在测量直流电机的电气特性之前，先将低压直流电源设置为0.8安培，并将电源端子连接到电机电枢。然后记录电源的电压和电流。接下来，使用万用表测量电枢、分流励磁绕组和串联励磁绕组两端的电压和电流。利用这些数据估算各部件的电阻。在测量完直流电机-发电机的基本特性后，将内置励磁变阻器调至最大阻值位置，并测量其电阻。最后，将外部串联励磁变阻器调至其上限位置，并测量其电阻。完成直流电机测试后，使用同步电机驱动直流电机的电枢旋转。此时，直流电机作为发电机运行，先在无励磁磁场、空载的条件下运行。在此情况下，端电压等于感应电动势（EMF）。测量发电机的转速，并用于计算电枢在无线圈励磁时仍保留的磁性，即残余磁性。首先，确认三相断路开关、同步电机和直流电机均处于关闭状态。然后，在直流电机的外部转子上粘贴一小段胶带。检查调压器（variac）是否已调至0%后，将调压器连接至三相电源插座。接着，按照图示连接实验装置。然后，确认“启动-运行”开关处于“启动”位置。在调节调压器之前，确认所有接线均已远离电源接线端。只有在确认无误后，才闭合三相断路开关。接下来，打开高压直流电源，按下VI显示按钮以显示运行端电流，并调节电压旋钮至125伏。在调节电压旋钮前，切勿按下启动按钮。按下直流电源面板上的启动按钮，并开启设备。随后，缓慢增加调压器输出，直至端电压读数为120伏。当同步电机达到稳定转速时，将“启动-运行”开关拨至“运行”位置。注意倾听电机声音的变化，电机在稳定状态下声音将变得单调。使用频闪仪通过将闪光频率与电机转速同步，使电机的转动看起来静止。当频闪仪与转速同步时，转子上的胶带将呈现静止状态。通过缓慢提高频闪频率，使风扇在下一个更高的同步频率下同步，以确认该频率即为电机转速。若正确，此频率应为首次观察到的频闪同步频率的两倍。每次后续测试运行前，均需重复此启动流程。启动完成后，记录电机的转速和电枢电压，并利用这些数据计算残余磁场强度。直流电机被应用于多种场合。在确定不同电机的工作参数后，可根据特定设备的设计要求选择合适的电机。直流发电机可通过多种构型进行表征，例如并励构型。在开关S1断开的情况下进行空载测试时，需将励磁绕组与负载电阻调节至最大阻值。随后，按照前述方法记录转轴转速和端电压。逐步减小并联电阻，共分五个步骤，直至达到最小阻值，并测量并联电阻两端的端电压和电流。电机也可采用负载电阻模拟负载，依照相同流程进行测量。每种类型的直流发电机具有其独特的电压-电流输出特性。并励发电机可在较宽的电流负载范围内提供稳定的电压，而串励发电机的输出电压则随电流负载的增加而上升。在多种需要无线电源的应用中，例如电动假肢，直流电机是首选的执行元件。在神经控制的下肢假肢中，通过体表或经皮传感器向替代肢体中的电动关节传递信号，其工作方式类似于健康下肢。相较于刚性假肢，这种设计能够更自然、更直观地控制步态和足部屈伸动作。您刚刚观看了 JoVE 关于直流电机的简介。现在您应该理解直流电机的工作原理以及如何表征其参数。感谢观看。

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电气工程

dc motors and generator action

DC machines use direct current and direct voltage to create motion or generate electricity. They were the first machines of this kind to be invented. A DC machine works with two magnetic fields that are controlled by DC currents, and the same machine can be set up as either a motor or a generator when the right field excitation is available.

In a DC machine, the field is usually on the stator side and the armature is on the rotor side. That arrangement is the reverse of what is found in many AC machines. The field can come from permanent magnets or from a winding, which is a coil of wire.

When current reaches the armature coil, it passes from the DC source through brushes and slip rings. The brushes stay still, while the slip rings are mounted on the rotating rotor and touch the brushes as the rotor turns. A current-carrying loop in the armature, when placed in the field from the stator or field magnet, feels a force.

Because the loop is supported by bearings, that force creates torque. Torque makes the rotor shaft spin instead of moving in some other direction. As the shaft turns, the magnetic fields line up, and the slip rings switch sides on the brushes. This switching is called commutation.

During commutation, the current in the rotor coil reverses. The magnetic fields then oppose each other again, which keeps producing torque in the same direction. The cycle repeats, and the rotor shaft continues to spin. That is how the machine produces motor action.

In generator operation, the process is reversed. Mechanical rotation is applied to the rotor shaft, and current is induced in the moving coil under a magnetic field. The machines discussed here use a field winding rather than permanent magnets.

Brushes and slip rings are critical because they transfer energy between the spinning rotor and the outside circuit. They are needed because spinning wires would twist and break. At the same time, these parts have reliability problems. They need regular maintenance, brush replacement, and cleaning, and they may also cause sparking.

These drawbacks have led most DC machines to be replaced by AC machines that do not have the same issues. The DC machines that remain are often simple systems with permanent magnet field excitation, such as toys and low-power tools. AC machines called brushless DC machines, or BLDCs, use a DC source and a power electronic inverter to produce AC voltages.

The experiment in this collection focuses on two DC machine setups: shunt and series. It also aims to estimate the residual flux in the machine. In addition, it studies the no-load and loading characteristics of the different configurations.

DC Motors and Generator Action

electrical safety precautions and basic equipment

electrical-safety-precautions-and-basic-equipment

Safe Handling of High-Voltage Lab Power

Safe handling of high-voltage lab power is essential in electric machine and power electronics experiments. These labs involve electrical currents, voltages, power, and energy that require extreme care. The systems used in this work can include three-phase AC voltage at 208 V, 230 V, or 480 V. They may also use up to 250 V DC and currents that can reach 10 A. These levels can be dangerous if handled without proper attention. Electrocution can happen when electricity passes through the body.

characterization of magnetic components

B-H Curves and Inductor Core Limits

Magnetic components such as inductors and transformers depend on the core material around their windings. In this experiment, students get hands-on experience with these parts from both a design view and a material view. The work focuses on B-H curves, which show the magnetic behavior of a material. A B-H curve describes the magnetic flux density the core can support as current flows through the windings. It also helps show the limit before magnetic saturation occurs. Magnetic saturation...

introduction to the power pole board

Power Pole Board for DC/DC Converter Labs

The HiRel Power Pole Board is a flexible tool for studying DC/DC converters. A DC/DC converter changes direct-current voltage and current from one level to another. In many cases, voltage conversion is the main goal. This board supports several converter types on one platform. It can be used to examine boost converters, which step voltage up, and buck converters, which step voltage down. It also helps students study buck-boost converters, which can step voltage up or down. The board is also...

dc/dc boost converter

Stepping Up DC Voltage with Boost Converters

DC voltage can be increased with a boost converter. This step-up circuit is useful in many applications where a DC source must be raised without first converting it to AC, using a transformer, and then rectifying the transformer output. A boost converter uses an inductor as an energy storage device. The inductor supports the output with extra energy in addition to the DC input source. That added energy raises the output voltage. This experiment studies several characteristics of a boost...

dc/dc buck converter

Buck Converter Step-Down DC Voltage

A DC/DC buck converter steps down DC voltage in an efficient, regulated way. Unlike transformers, which easily raise or lower AC voltage and current, DC systems need switching power converters to change voltage levels. The buck converter works by chopping the input DC voltage with a series input switch. An L-C low-pass filter then smooths the chopped signal and extracts the average output voltage. A diode gives the inductor current a path when the switch is off during part of the switching...

flyback converter

Flyback Converter Voltage Step-Up and Step-Down

A flyback converter is a buck-boost converter that can both step voltage up and step it down. It also provides electrical isolation between the input and the output by using a coupled inductor, or flyback transformer. The coupled inductor acts like a transformer with a turns ratio, but it also stores energy through the air gap. This setup gives the converter both voltage step-up and step-down capability. In the experiment, the converter is studied in open-loop operation with a manually set...

single phase transformers

Single Phase Transformer Testing

Single-phase transformers step up or step down AC voltage in electric power systems. They are stationary electric machines with primary and secondary coils, also called windings. The primary winding receives the applied voltage, and the secondary winding delivers the changed voltage. Inside the transformer, current in one winding creates magnetic flux in the core. This flux links the two windings and transfers energy between them. With AC current, the changing flux induces voltage in the...

single phase rectifiers

AC to DC Conversion with Rectifiers

Rectifiers convert AC power into DC power for electronic circuits. A DC power supply provides unidirectional voltage and current. Batteries can do this, but they are limited by lifetime and cost. Using a rectifier is another way to turn AC line power into DC power. A rectifier is a device that lets current pass in one direction and blocks it in the other. It works after a forward voltage threshold is reached. Rectifiers may use a diode, a silicon controlled rectifier, or other silicon P-N...

thyristor rectifier

Controlling SCR Half-Wave Rectification

Thyristors, also called silicon controlled rectifiers (SCRs), are used to control current in a rectifier circuit. Like diodes, they let current pass from the anode to the cathode and block current in the opposite direction. Unlike a diode, a thyristor can be turned on with a gate terminal that receives a small current pulse. A thyristor is a four-layer device with alternating n-type and p-type layers. These layers form a PNPN structure with three junctions. The device has three terminals. The...

single phase inverter

DC to AC Conversion with Half-Bridge Inverters

DC to AC conversion is the main idea behind a power inverter. DC power flows in one direction, while AC current changes direction at about 50-60 Hz. Many electronic devices are designed to run on AC power, so a DC source must be inverted before it can be used with them. An inverter makes this change through switching action. The switches repeatedly flip the polarity of the input DC source at the output, or load side, for part of a switching period. A typical power inverter needs a stable DC...

dc motors

DC machines use direct current and direct voltage to create motion or generate electricity. They were the first machines of this kind to be invented. A DC machine works with two magnetic fields that are controlled by DC currents, and the same machine can be set up as either a motor or a generator when the right field excitation is available. In a DC machine, the field is usually on the stator side and the armature is on the rotor side. That arrangement is the reverse of what is found in many...

ac induction motor characterization

Three-Phase Motor Equivalent Circuit Tests

Three-phase induction motor testing can be used to find equivalent circuit parameters. The experiment uses the per-phase equivalent circuit to model the motor. This model keeps the important behavior of the original system and makes calculations easier. The procedure uses tests similar to those used in transformer characterization. These measurements help estimate the motor's circuit values from its electrical response. The experiment also aims to operate the motor in the linear torque-speed...

vfd-fed ac induction machine

Variable Frequency Drive Speed Control

Variable frequency drives, or VFDs, control the speed of AC induction motors. They are a type of adjustable speed drive and are becoming standard equipment for powering most AC induction motors. In industrial and automation settings, VFDs can provide strong control of motor speed, torque, or position. This experiment focuses on speed control with open-loop operation. It uses constant voltage-to-frequency ratio control, also called V/f control. The motor usually operates at a rated stator flux,...

ac synchronous machine synchronization

Grid Connection of AC Synchronous Generators

AC synchronous generators are a major source of electrical power worldwide. They are three-phase, wound-rotor machines that are used in many power plants. These generators need a prime mover and an exciter to produce power. A prime mover is the device that spins the generator, often a turbine driven by fluid. That fluid can come from water flowing from a dam through a long nozzle or from steam made by burning coal. Most power plants use synchronous generators, including coal, nuclear, natural...

ac synchronous machine characterization

Three-Phase Synchronous Motor Starting and V-Curves

Three-phase synchronous motors and generators are important AC machines. Wound-rotor synchronous motors are less common than permanent magnet rotor synchronous motors because the rotor field uses brushes. Synchronous generators are much more common. They are used in most existing power plants because they provide excellent frequency and voltage regulation. A synchronous motor runs at the same speed as the stator magnetic field. This gives it almost 0% speed regulation, so the rotor speed stays...

electrical engineering

本系列从电气安全视频开始, 介绍了电气实验室中常用设备的最佳实践。随后的视频介绍了电感器、变压器、变流器、整流器和逆变器等元素。

Explore how DC machines use brushes, slip rings, commutation, and field excitation to act as motors or generators, with shunt and series tests.

DC Motors and Generator Action | JoVE K12

south-carolina-college-and-career-ready-science-standards

South Carolina College and Career Ready Science Standards

Physics

motion-and-stability-forces-and-interactions

Motion and Stability: Forces and Interactions

P-PS2-6.

Georgia Standards of Excellence

9-12

SP5.

Applications in Motors and Generators

Ali Bazzi

Overview

Principles of DC Motors

DC Tests

Measurement of Residual Magnetism

Applications

Summary

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HS.P3U1.6

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DC Motors and Generator Action

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