Motors are ubiquitous in the field of equipment

这是一个不孤单的设备
It’s a device that doesn’t stand alone

靠谱的泵需要靠谱的电机
A reliable pump needs a reliable motor

电机的好坏直接影响着设备能否正常运行
The quality of the motor directly affects the normal operation of the equipment

电机类型、软启动方式，选型步骤，损坏原因方式处理方法，优劣电机区别…..这一个个问题都是电机幸福指数的重要反映。
Motor type, soft start mode, selection steps, damage cause method, treatment method, difference between good and bad motors….. These problems are an important reflection of the motor happiness index.

下面就让我们一同看看
Let’s take a look

电机基础知识01
Motor Basics 01

各类电机的区别
The difference between various types of motors

1、直流、交流电机区别
The difference between DC and AC motors

直流电机结构示意图
Schematic diagram of DC motor structure

交流电机结构示意图
Schematic diagram of AC motor structure

顾名思义
Name implies

直流电机使用直流电做为电源，
DC motors use direct current as a power source.

而交流电机是使用交流电做为电源。
AC motors, on the other hand, use alternating current as a power source.

从结构上说，直流电机的原理相对简单，但结构复杂，不便于维护。
Structurally speaking, the principle of DC motor is relatively simple, but the structure is complex and not easy to maintain.

而交流电机原理复杂但结构相对简单，而且比直流电机便于维护。
The principle of AC motor is complex but the structure is relatively simple, and it is easier to maintain than DC motor.

在价格方面，功率相同的直流电机高于交流电机。
In terms of price, DC motors with the same power are higher than AC motors.

包括控制速度的调速装置，也是直流高于交流的价格，当然结构和维护也有很大的差异。
Including the speed control device, the price of DC is higher than that of AC, of course, the structure and maintenance are also very different.

而在性能方面，因直流电机的速度稳定，转速控制精准，是交流电机无法达到的，所以在转速的严格要求下不得不采用直流电机替代交流电机。
In terms of performance, due to the stable speed and accurate speed control of the DC motor, which cannot be achieved by the AC motor, the DC motor has to be used instead of the AC motor under the strict requirements of the speed.

交流电机调速相对复杂，但却由于化工厂使用交流电源而应用广泛。
AC motors are relatively complex to regulate speed, but they are widely used due to the use of AC power in chemical plants.

2同步、异步两类电机区别
There is a difference between synchronous and asynchronous motors

转子的旋转速度与定子一样，那就叫同步电动机。
The rotor rotates at the same speed as the stator, so it is called a synchronous motor.

如若不一致，则叫异步电动机。
If it is inconsistent, it is called an asynchronous motor.

3普通、变频两类电机区别
The difference between ordinary and inverter motors

首先明确一点，普通电机并不能当变频电机来使用。
First of all, it is clear that ordinary motors cannot be used as inverter motors.

普通电机是按恒频恒压来设计的，不可能完全适应变频器调速的要求，因此不能当做变频电机使用。
The ordinary motor is designed according to the constant frequency and constant voltage, and it is impossible to fully adapt to the requirements of the frequency converter speed regulation, so it cannot be used as a frequency conversion motor.

变频器对电机的影响
The influence of the inverter on the motor

主要在电动机的效率和温升
Mainly in the efficiency of the motor and the temperature rise

变频器在运行中能产生不同程度的谐波电压和电流，使电动机在非正弦电压、电流下运行，里面的高次谐波会引起电动机定子铜耗、转子铜耗、铁耗及附加损耗增加。
The inverter can produce different degrees of harmonic voltage and current during operation, so that the motor runs under non-sinusoidal voltage and current, and the higher harmonics in it will cause the increase of stator copper consumption, rotor copper consumption, iron consumption and additional loss of the motor.

其中最为显著的是转子铜耗，这些损耗会使电动机额外发热，效率降低，输出功率减小，普通电动机温升一般要增加10%－20%。
Among them, the most significant is the copper loss of the rotor, which will cause the motor to generate additional heat, reduce efficiency, reduce the output power, and increase the temperature rise of ordinary motors by 10%-20%.

变频器载波频率从几千赫到十几千赫，使得电动机定子绕组要承受很高的电压上升率，相当于对电动机施加陡度很大的冲击电压，使电动机的匝间绝缘承受较为严重的考验。
The carrier frequency of the inverter ranges from a few thousand hertz to more than ten thousand hertz, which makes the stator winding of the motor bear a high voltage rise rate, which is equivalent to applying a steep impulse voltage to the motor, so that the inter-turn insulation of the motor can withstand a more serious test.

普通电动机采用变频器供电时，会使由电磁、机械、通风等因素所引起的震动和噪声变的更加复杂。
When ordinary motors are powered by inverters, the vibration and noise caused by electromagnetic, mechanical, ventilation and other factors will become more complicated.

而变频电源中含有的各次谐波与电动机电磁部分固有空间谐波相互干涉，形成各种电磁激振力，从而加大噪声。
The harmonics contained in the variable frequency power supply interfere with the inherent space harmonics of the electromagnetic part of the motor to form various electromagnetic excitation forces, thereby increasing the noise.

由于电动机的工作频率范围宽，转速变化范围大，各种电磁力波的频率很难避开电动机的各结构件的固有振动频率。
Due to the wide working frequency range of the motor and the wide range of speed changes, it is difficult for the frequencies of various electromagnetic force waves to avoid the natural vibration frequencies of each structural part of the motor.

当电源频率较低时，电源中的高次谐波所引起的损耗较大；其次变通电机转速降低时，冷却风量与转速的三次方成正比减小，致使电机热量散发不出去，温升急剧增加，难以实现恒转矩输出。（我们推荐你关注“机械工程师”公众号，第一时间掌握干货知识、行业信息）
When the frequency of the power supply is low, the loss caused by the higher harmonics in the power supply is larger; Secondly, when the speed of the switch-through motor is reduced, the cooling air volume decreases proportionally to the cubic of the speed, resulting in the heat of the motor not being dissipated, the temperature rise increases sharply, and it is difficult to achieve constant torque output. (We recommend that you pay attention to the “Mechanical Engineer” public account to grasp the knowledge of dry goods and industry information at the first time)

如何区分普通电机和变频电机？
How to distinguish between ordinary motors and inverter motors?

普通电机和变频电机结构上的区别
The difference between the structure of ordinary motor and inverter motor

01.绝缘等级要求更高
01. Higher requirements for insulation grade

一般变频电机的绝缘等级为F级或更高，加强对地绝缘和线匝绝缘强度，特别要考虑绝缘耐冲击电压的能力。
Generally, the insulation grade of the inverter motor is F or higher, and the insulation strength of the ground insulation and line turns should be strengthened, especially the ability of the insulation to withstand the impulse voltage.

02.变频电机的振动、噪声要求更高
02. The vibration and noise requirements of the inverter motor are higher

变频电机要充分考虑电动机构件及整体的刚性，尽力提高其固有频率，以避开与各次力波产生共振现象。
The inverter motor should fully consider the rigidity of the motor mechanism and the whole, and try to increase its natural frequency to avoid resonance with each force wave.

03.变频电机冷却方式不同
03. The cooling method of the inverter motor is different

变频电机一般采用强迫通风冷却，即主电机散热风扇采用独立的电机驱动。
Inverter motors generally use forced ventilation cooling, that is, the main motor cooling fan is driven by an independent motor.

04.保护措施要求不同
04. Different requirements for protective measures

对容量超过160KW变频电动机应采用轴承绝缘措施。主要是易产生磁路不对称，也会产生轴电流，当其他高频分量所产生的电流结合一起作用时，轴电流将大为增加，从而导致轴承损坏，所以一般要采取绝缘措施。对恒功率变频电动机，当转速超过3000/min时，应采用耐高温的特殊润滑脂，以补偿轴承的温度升高。
Bearing insulation measures should be used for variable frequency motors with a capacity of more than 160KW. When the current generated by other high-frequency components is combined, the shaft current will increase greatly, resulting in bearing damage, so insulation measures should generally be taken. For constant power variable frequency motors, when the speed exceeds 3000/min, special grease with high temperature resistance should be used to compensate for the temperature increase of the bearing.

05.散热系统不同
05. The heat dissipation system is different

变频电机散热风扇采用独立电源供电，保证持续的散热能力。
The inverter motor cooling fan is powered by an independent power supply to ensure continuous heat dissipation capacity.

电机基础知识02
Motor Basics 02

电机的选型
Selection of motors

电机选型需要的基本内容有：
The basic contents required for motor selection are:

所驱动的负载类型、额定功率、额定电压、额定转速、其他条件。
The type of load driven, the rated power, the rated voltage, the rated speed, and other conditions.

负载类型
The type of load

·直流电机
DC motors

·异步电机
Asynchronous motor

·同步电机
Synchronous motors

负载平稳，对起、制动无特殊要求的连续运行的生产机械，宜优先选用普通鼠笼型异步电动机，其广泛用于机械、水泵、风机等。
For production machinery with stable load and no special requirements for lifting and braking, it is advisable to give preference to ordinary squirrel cage asynchronous motors, which are widely used in machinery, water pumps, fans, etc.

起动、制动比较频繁，要求有较大的起动、制动转矩的生产机械，如桥式起重机、矿井提升机、空气压缩机、不可逆轧钢机等，应采用绕线式异步电动机。
Winding asynchronous motors should be used for production machinery that starts and brakes more frequently and requires larger starting and braking torques, such as overhead cranes, mine hoists, air compressors, irreversible rolling mills, etc.

无调速要求，需要转速恒定或要求改善功率因数的场合，应采用同步电动机，例如中、大容量的水泵，空气压缩机、提升机、磨机等。
There is no requirement for speed regulation, and the speed needs to be constant or the power factor needs to be improved, synchronous motors should be used, such as medium and large capacity water pumps, air compressors, hoists, mills, etc.

调速范围要求在1∶3以上，且需连续稳定平滑调速的生产机械，宜采用他励直流电动机或用变频调速的鼠笼式异步电动机或同步电机，例如大型精密机床、龙门刨床、轧钢机、提升机等。
For production machinery that requires a speed regulation range of more than 1:3 and requires continuous, stable and smooth speed regulation, it is advisable to use separately excited DC motors or squirrel cage asynchronous motors or synchronous motors with frequency conversion speed regulation, such as large-scale precision machine tools, gantry planers, rolling mills, hoists, etc.

要求起动转距大，机械特性软的生产机械，使用串励或复励直流电动机，例如电车、电机车、重型起重机等。
Production machinery that requires a large starting distance and soft mechanical characteristics use series or compound excitation DC motors, such as trams, electric locomotives, heavy cranes, etc.

一般来说，提供了驱动的负载类型、电机的额定功率、额定电压、额定转速便可以将电机大致确定下来。
Generally speaking, the type of load driven, the rated power, the rated voltage, and the rated speed of the motor can be roughly determined.

但如果要最优化地满足负载要求，这些基本参数就远远不够了。
However, if the load requirements are to be optimally met, these basic parameters are not sufficient.

还需要提供的参数包括：
Parameters that also need to be provided include:

频率，工作制，过载要求，绝缘等级，防护等级，转动惯量，负载阻力矩曲线，安装方式，环境温度，海拔高度，户外要求等（根据具体情况提供）
Frequency, working system, overload requirements, insulation level, protection level, moment of inertia, load resistance torque curve, installation method, ambient temperature, altitude, outdoor requirements, etc. (provided according to the specific situation)

电机基础知识03
Motor Basics 03

电机故障排查步骤
Steps for motor selection

电动机运行或故障时，
When the motor is running or malfunctioning,

可通过看、听、闻、摸四种方法来及时预防和排除故障，
Faults can be prevented and eliminated in time by seeing, hearing, smelling, and touching.

以保证电动机的安全运行。
In order to ensure the safe operation of the motor.

一、看
1. Look

观察电动机运行过程中有无异常，其主要表现为以下几种情况。 
Observe whether there is any abnormality in the operation of the motor, which is mainly manifested in the following situations.

1.定子绕组短路时，可能会看到电动机冒烟。 
1. When the stator winding is short-circuited, you may see smoke coming from the motor.

2.电动机严重过载或缺相运行时，转速会变慢且有较沉重的”嗡嗡”声。 
2. When the motor is seriously overloaded or out of phase, the speed will slow down and there will be a heavy “hum” sound.

3.电动机维修网正常运行，但突然停止时，会看到接线松脱处冒火花;保险丝熔断或某部件被卡住等现象。 
3. The motor maintenance network is operating normally, but when it stops suddenly, you will see sparks coming from the loose wiring; Phenomena such as a blown fuse or a stuck component.

4.若电动机剧烈振动，则可能是传动装置被卡住或电动机固定不良、底脚螺栓松动等。 
4. If the motor vibrates violently, it may be that the transmission device is stuck or the motor is poorly fixed, the foot bolts are loose, etc.

5.若电动机内接触点和连接处有变色、烧痕和烟迹等，则说明可能有局部过热、导体连接处接触不良或绕组烧毁等。
5. If there are discoloration, burn marks and smoke marks at the contact points and connections in the motor, it means that there may be local overheating, poor contact at the conductor connection or burning of the winding.

二、听
2. Listen

电动机正常运行时应发出均匀且较轻的”嗡嗡”声，无杂音和特别的声音。
When the motor is operating normally, it should emit a uniform and light “hum” sound, without noise and special sounds.

若发出噪声太大，包括电磁噪声、轴承杂音、通风噪声、机械摩擦声等，均可能是故障先兆或故障现象。 
If the noise is too large, including electromagnetic noise, bearing noise, ventilation noise, mechanical friction sound, etc., it may be a precursor or fault phenomenon.

1. 对于电磁噪声，如果电动机发出忽高忽低且沉重的声音，则原因可能有以下几种:
1. For electromagnetic noise, if the motor emits a high and low and heavy sound, the causes may be as follows:

(1)定子与转子间气隙不均匀，此时声音忽高忽低且高低音间隔时间不变，这是轴承磨损从而使定子与转子不同心所致。（我们推荐你关注“机械工程师”公众号，第一时间掌握干货知识、行业信息）
(1) The air gap between the stator and the rotor is uneven, and the sound is high and low and the interval between high and low bass is unchanged, which is caused by the wear of the bearing so that the stator and the rotor are not concentrified. (We recommend that you pay attention to the “Mechanical Engineer” public account to grasp the knowledge of dry goods and industry information at the first time)  

(2)三相电流不平衡。这是三相绕组存在误接地、短路或接触不良等原因，若声音很沉闷则说明电动机严重过载或缺相运行。 
(2) Three-phase current unbalance. This is the reason that the three-phase winding has misgrounding, short circuit or poor contact, etc., if the sound is very dull, it means that the motor is seriously overloaded or out of phase operation.

(3)铁芯松动。电动机在运行中因振动而使铁芯固定螺栓松动造成铁芯硅钢片松动，发出噪声。 
(3) The iron core is loose. During the operation of the motor, the core fixing bolt is loosened due to vibration, resulting in the loosening of the core silicon steel sheet and the noise.

2.对于轴承杂音，应在电动机运行中经常监听。
2. For bearing noise, it should be monitored frequently during the operation of the motor.

监听方法是：将螺丝刀一端顶住轴承安装部位，另一端贴近耳朵，便可听到轴承运转声。若轴承运转正常，其声音为连续而细小的”沙沙”声，不会有忽高忽低的变化及金属摩擦声。
The monitoring method is to hold one end of the screwdriver against the bearing mounting part and the other end close to the ear, and the bearing operation sound can be heard. If the bearing is running normally, the sound is a continuous and small “rustling” sound, and there will be no high and low changes and metal friction sounds.

若出现以下几种声音，则为不正常现象:
If the following sounds are present, it is abnormal:

(1)轴承运转时有”吱吱”声，这是金属摩擦声，一般为轴承缺油所致，应拆开轴承加注适量润滑脂。 
(1) There is a “squeak” sound when the bearing is running, which is the sound of metal friction, which is generally caused by the lack of oil in the bearing, and the bearing should be disassembled and filled with an appropriate amount of grease.

(2)若出现”唧哩”声，这是滚珠转动时发出的声音，一般为润滑脂干涸或缺油引起，可加注适量油脂。 
(2) If there is a “chirping” sound, which is the sound made when the ball rotates, it is generally caused by the drying up of grease or lack of oil, and an appropriate amount of grease can be added.

(3)若出现”喀喀”声或”嘎吱”声，则为轴承内滚珠不规则运动而产生的声音，这是轴承内滚珠损坏或电动机长期不用，润滑脂干涸所致。 
(3) If there is a “click” sound or “crunch” sound, it is the sound produced by the irregular movement of the balls in the bearing, which is caused by the damage of the balls in the bearing or the long-term use of the motor and the drying up of the grease.

3.若传动机构和被传动机构发出连续而非忽高忽低的声音，可分以下几种情况处理。
3. If the transmission mechanism and the driven mechanism emit continuous sound instead of high and low, it can be divided into the following situations.

(1)周期性”啪啪”声，为皮带接头不平滑引起。 
(1) Periodic “popping” sound is caused by the unevenness of the belt joint.

(2)周期性”咚咚”声，为联轴器或皮带轮与轴间松动以及键或键槽磨损引起。 
(2) Periodic “knock” sound, caused by the loosening between the coupling or pulley and the shaft, as well as the wear of the key or keyway.

(3)不均匀的碰撞声，为风叶碰撞风扇罩引起。 
(3) The uneven collision sound is caused by the fan blade colliding with the fan cover.

三、闻
3. Smell

通过闻电动机的气味也能判断及预防故障。
By smelling the smell of the motor, it is also possible to detect and prevent malfunctions.

打开接线盒用鼻子嗅
Open the junction box and sniff with your nose

看是否有焦糊味，若发现有特殊的油漆味，说明电动机内部温度过高；若发现有很重的糊味或焦臭味，则可能是绝缘层维修网被击穿或绕组已烧毁。
If there is a special smell of paint, it means that the internal temperature of the motor is too high; If a strong mushy or burnt smell is found, it may be that the insulation repair net has been broken down or the windings have been burned.

如果没有味道，还需要用兆欧表测其绕组与外壳之间的绝缘阻值低于0.5兆，得进行烘干处理。阻值为零，说明已经损坏。
If there is no smell, it is also necessary to use a megohmmeter to measure the insulation resistance between the winding and the shell to be less than 0.5 trillion, and it must be dried. If the resistance value is zero, it means that it has been damaged.

四、摸  
Fourth, touch

摸电动机一些部位的温度也可判断故障原因。
The cause of the fault can also be judged by touching the temperature of some parts of the motor.

为确保安全，用手摸时应用手背去碰触电动机外壳、轴承周围部分。
In order to ensure safety, the back of the hand should be used to touch the motor housing and the surrounding parts of the bearing.

若发现温度异常，其原因可能有以下几种： 
If an abnormal temperature is found, it may be due to the following reasons:

1.通风不良。如风扇脱落、通风道堵塞等。 
1. Poor ventilation. Such as fan falling off, ventilation duct blockage, etc.

2.过载。致使电流过大而使定子绕组过热。 
2. Overload. As a result, the current is too large and the stator winding is overheated.

3.定子绕组匝间短路或三相电流不平衡。 
3. Stator winding inter-turn short circuit or three-phase current unbalance.

4.频繁启动或制动。 
4. Frequent starting or braking.

5.若轴承周围温度过高，则可能是轴承损坏或缺油所致。
5. If the temperature around the bearing is too high, it may be caused by bearing damage or lack of oil.

电机轴承温度规定、出现异常的原因及处理
Motor bearing temperature regulations, abnormal causes and treatment

规程规定，滚动轴承最高温度不超过95℃，滑动轴承最高温度不超过80℃。并且温升不超过55℃（温升为轴承温度减去测试时的环境温度）。
The regulations stipulate that the maximum temperature of rolling bearings should not exceed 95 °C, and the maximum temperature of plain bearings should not exceed 80 °C. And the temperature rise does not exceed 55°C (the temperature rise is the bearing temperature minus the ambient temperature at the time of the test).

轴承温升过高的原因及处理： 
Causes and treatment of high bearing temperature rise:

(1)原因：轴弯曲，中心线不准。
(1) Reason: the shaft is bent and the center line is not accurate.

  处理：重新找中心。 
Processing: Re-centering.

(2)原因：基础螺丝松动。
(2) Reason: Loose foundation screws.

  处理：拧紧基础螺丝。
Treatment: Tighten the foundation screws.

 

(3)原因：润滑油不干净。
(3) Reason: The lubricating oil is not clean.

  处理：更换润滑油。
Treatment: Replace the lubricating oil.

(4)原因：润滑油使用时间过长，未更换。
(4) Reason: The lubricating oil has been used for too long and has not been replaced.

  处理：洗净轴承，更换润滑油。 
Treatment: Wash the bearings and replace the lubricating oil.

(5)原因：轴承中滚珠或滚柱损坏。
(5) Reason: Damage to the ball or roller in the bearing.

  处理：更换新轴承。
Treatment: Replace the bearing with a new one.

解决方法：
Solution(s):

1.打开模块盖板，更换模块中已经损坏的保险、充电电阻等元器件。
1. Open the cover plate of the module and replace the damaged components such as the fuse and charging resistor in the module.

2.更换损坏的光通子板或者保护二极管。
2. Replace the damaged optical flux daughter board or protection diode.

3.光纤按照标示正常连接，光纤损坏的话进行更换。
3. The optical fiber is connected normally according to the label, and the optical fiber will be replaced if it is damaged.

4.更换模块电源板。
4. Replace the module power strip.