马拉松发电机维修保养.doc

马拉松发电机维修保养
上海马拉松发电机
产品概述
MP系列500机座无刷三相交流同步发电机是在美国马拉松电气公司（Marathon Electric U.S.A）提供的MAGNAPLUS图纸基础上，新开发改进设计的新型无刷发电机。
MP系列500机座发电机与柴油机配套组成固定或移动电源，适用于各种场合，也可用作应急发电电源。MP系列发电机设计独特，结构先进，性能优良，运行可靠，使用方便，适合各种应用需要和气候条件，代表目前国际先进水平。
卓越的电器性能
1、稳态调压率≤1%
2、顺态调压率＋20%－15%Un（60%In.cosφ≤0.4滞后）
3、电压调节范围＞±10%Un
4、线压波形正弦性畸变率＜5%
5、热偏差为零（极微）
独特的结构设计
1、发电机为全防护结构，内部通风散热结构独特，铝合金风扇，通风率高，温升低。
2、无刷励磁方式，配有固态电压调压器，调压器具有低速保护，电磁干扰抑制，过励关断等功能，且带有稳定性调节和电压幅度调节。
3、整体凸极转子结构，阻尼绕组与转子铁心连成为一体，磁场绕组采用热固性环氧填充，有较高的机械和电气强度。
4、旋转整流器位于励磁机转子外侧，便于维修。
5、出线箱宽敞，内部可加装各种器件。出线箱位于机座后面上方，美观紧凑。
6、绝缘等级为H级。
7、按客户要求可提供用于并联运行的模块及附加装置。
8、发电机分单轴承和双轴承两中结构。
单轴承带有国际标准的SAE接口和联轴器片，能与各类进口油机配套。
双轴承适应国内各种柴油机的配套，按客户要求配置各种尺寸的凸缘止口。
9、根据客户需要可以加装PMG及使用DVR2000E数字式调压器。
10、根据客户需要可以加装防冷凝加热管和热保护元件。
使用条件
空气温度不超过：40℃
海拔高度不超过：1000米
如使用条件不符合上述环境，必须按规定修正功率输出定额。
电压、频率、转速、功率因数及工作方式
额定电压：400伏（480伏60赫兹时）
额定频率：50赫兹或60赫兹
额定转速：1500转/分或1800转/分
功率因数：0.8滞后
工作方式：连续（S1）
根据客户需要，可制成不同输出电压，或其它特殊要求的产品。
并联运行
MP发电机都可连续并联运行，为保证发电机运行稳定，转子上都装有全阻尼绕组。
发电机并联运行时，有功负载的分配由柴油机调速器调节实现，无功负载的分配由发电机调压器实现。
配有SE350的发电机并联运行时，需配用APM2000并联模块和5VA的电流互感器，采用电压下垂或横流补偿来保证并联发电机之间无功负载分配的均衡。
配有PMG和DVR2000E调压器的发电机，由于DVR调压器中包含了并联运行功能，只需提供5VA电流互感器的信号给调压器即可。
抗电磁干扰
装有SE350调压器的发电机符合普通级，配DVR2000E数字式调压器的发电机符合MiL-461c
轴承
MP发电机使用的轴承是双面防尘滚动球轴承，一次性润滑，特殊的高性能润滑脂，正常使用情况下，B10≥20000小时。

同步发电机要用直流电流励磁。在以往的他励式同步发电机中，其直流电流是有附设的直流励磁机供给。直流励磁机是一种带机械换向器的旋转电枢式交流发电机。其多相闭合电枢绕组切割定子磁场产生了多相交流电，由于机械换向器和电刷组成的整流系统的整流作用，在电刷上获得了直流电，再通过另一套电刷，滑块系统将获得的直流输送到同步发电机的转子，励磁绕组去励磁，因此直流励磁机的换向器原则上是一个整流器，显然可以用一组硅二节管取代，而功率半导体器件的发展提供了这个条件。将半导体元件与发电机的轴固结在一起转动，则可取消换向器、滑块等滑动接触部分、利用二极管换成直流电流。直流送给转子励磁、绕组励磁。这就是无刷系统。
下面我们以典型的几种不同发电机励磁系统，介绍它的工作原理。
一、相复励励磁原理
左图为常用的电抗移相相复励励磁系统线路图。由线形电抗器DK把电枢绕组抽头电压移相约90°、和电流互感器LH提供的电压几何叠加，经过桥式整流器ZL整流，供给发电机励磁绕组。负载时由电流互感器LH供给所需的复励电流，进行电流补偿，由线形电抗器DK移相进行相位补偿。
二、三次谐波原理
左图为三次谐波原理图，对一般发电机来源，我们需要的是工频正弦波，称为基波，比基波高的正弦波都称为谐波、其中三次谐波的含量最大，在谐波发电机定子槽中，安放有主绕组和谐波励磁绕组（s1、s2），而这个绕组之间没有电的联系。谐波绕组将绕组中150HZ谐波感应出来，经过ZL桥式整流器整流，送到主发电机转子绕组LE中进行励磁。
三、可控硅直接励磁原理
由左图可以看出，可控硅直接励磁 是采用可控硅整流器直接将发电机输出的任一相一部分能量，经整流后送入励磁绕组去的励磁方式，它是由自动电压调节器（AVR），控制可控硅的导通角来调节励磁电流大小而维持发电机端电压的稳定。
四、无刷励磁原理
无刷励磁主要用于西门子、斯坦福、利莱等无刷发电机。它是利用交流励磁机，其定子上的剩磁或永久磁铁（带永磁机）建立电压，该交流电压经旋转整流起整流后，送入主发电机的励磁绕组，使发电机建压。自动电压调节器（AVR）能根据输出电压的微小偏差迅速地减小或增加励磁电流，维持发电机的所设定电压近似不变。

Marathon generator repair and maintenance
Shanghai Marathon generator
Product Overview
    MP Series 500 base brushless three-phase AC synchronous generator is in the Marathon Electric Company (Marathon Electric, USA) MAGNAPLUS drawings on the basis of the new development to improve the design of the new brushless generator.
    Generators and diesel engines of 500 MP series base composed of a fixed or mobile power, for various occasions, and can also be used as emergency power sources. MP series generator design is unique, advanced structure, excellent performance, reliable, easy to use, suitable for a variety of application needs and climatic conditions, on behalf of the international advanced level.
Excellent electrical properties
1, steady-state voltage regulation rate ≤ 1%
2, cis-state voltage regulation rate of +20% -15% Un (60% In.cosφ ≤ 0.4 lag)
3, the voltage adjustment range ± 10% Un
4, the line voltage sinusoidal waveform distortion rate <5%
5, the thermal deviation is zero (minimal)
Unique structural design
1, generator cooling structure of the protective structure, internal ventilation, unique aluminum alloy fan, ventilation rate, low temperature rise.
Brushless excitation method with solid state voltage regulator, voltage regulator with low protection, electromagnetic interference suppression, and overexcitation shutdown functions, and with stability adjustment and adjust the voltage amplitude.
3, the whole salient pole rotor structure, the damper winding and rotor core even become one, the field winding with thermosetting epoxy filling, high mechanical and electrical strength.
4, the rotating rectifier in the exciter rotor lateral, ease of maintenance.
5, the outlet box is spacious and can be installed within the device. The outlet box is located above the back of the docking station, beautiful compact.
6, insulation class H.
7, according to customer requirements to provide for parallel operation of modules and add-on devices.
8, the generator is divided into two in the structure of the single bearing and the double bearing.
Single bearing with the international standard SAE interfaces and the coupling piece, matching with the various types of imported oil machine.
Double bearings to adapt to domestic diesel engine supporting only the mouth of the flange of the configuration of various sizes according to customer requirements.
9, can be installed according to customer needs the PMG and use DVR2000E of digital regulator.
10, anti-condensation heating pipes and thermal protection components can be installed according to customer needs.
Conditions of Use
The air temperature does not exceed: 40 ° C
Altitude does not exceed: 1000 m
If conditions do not meet the above environment, must be required to amend the power output quotas.
Voltage, frequency, speed, power factor, and ways of working
Rated voltage: 400 volts (480 volts at 60 Hz)
Rated frequency: 50 Hz or 60 Hz
Rated speed: 1500 rev / min or 1800 rev / min
Power Factor: 0.8 lag
Operating mode: Continuous (S1)
Based on customer needs, can be made into different output voltages, or other special requirements.
Parallel operation
The MP generator can be continuous parallel operation, in order to ensure the stability of the generator is running, are equipped with damper windings on the rotor.
When the generator parallel operation, the power load distribution of the diesel engine governor adjust to achieve the reactive load assigned by the generator voltage regulator.
With SE350 generators operating in parallel, be equipped with the APM2000 in parallel module, 5VA of current transformer, voltage droop or cross-flow compensation to guarantee a balanced load distribution between the parallel generator reactive power.
Generator with PMG and DVR2000E of regulator, DVR regulator with parallel operation, only providing the 5VA current transformer signal to the voltage regulator can be.
Anti-electromagnetic interference
    Generator equipped with SE350 regulator to meet the ordinary level, with DVR2000E digital regulator generator comply with MiL-461c
Bearing
    MP generator bearings are double-sided dust rolling ball bearings, one-time lubrication, special high performance grease, B10, ≥ 20 000 hours under normal use.

Use DC current excitation of synchronous generator. In the past, excited synchronous generator, the DC current is attached to the DC exciter supply. DC exciter rotating armature AC generator with a mechanical commutator. Its closed multiphase armature winding cutting the stator magnetic field to produce a polyphase alternating current rectifying action of the mechanical commutator and brushes composed of rectifier system in the brush on the DC, and then through another set of brushes, the slider DC system will get transported to the synchronous generator rotor field winding to the excitation DC exciter commutator in principle, a rectifier, apparently you can use a set of silicon two pipes to replace the development of power semiconductor devices this condition. Axis consolidation of semiconductor components and generator with rotation, you can cancel the commutator, the slider sliding contact part, the use of diodes to replace the DC current. DC gave the rotor excitation winding excitation. This is the brushless system.
Here we have several typical generator excitation system, introduced it works.
One phase compound excitation principle
Left is a circuit diagram of the reactor shift phase phase compound excitation system. Shift similar to the tap voltage of the armature winding by linear reactance DK 90 °, the geometric superposition of the voltage and current transformers LH after the bridge rectifier ZL rectifier supply the generator field winding. Supply required by the current transformer LH compound excitation current, load current compensation, DK phase-shifting phase compensation by linear reactor.
Second and third harmonic principle
Left diagram for the third harmonic principle, the general source of the generator, we need the power frequency sine wave called the fundamental sine wave, Biji Bo are called harmonic, third harmonic content in the harmonic generator stator slot, placed the main winding and harmonic excitation windings (s1, s2), while there is no electrical contact between windings. Harmonic winding winding 150HZ harmonic induction, ZL bridge rectifier, rectifier, sent to the main generator rotor windings LE for excitation.
, SCR direct excitation principle
It can be seen by the left, the direct excitation of the SCR is to use silicon-controlled rectifier to the generator output directly to any part of the energy excitation mode to go into the field winding, the rectifier after, it is by the automatic voltage regulator ( AVR), control of the SCR conduction angle to adjust the excitation current size while maintaining the stability of the generator terminal voltage.
, Brushless excitation principle
Brushless excitation for brushless generator such as Siemens, Stanford, Rich. It is the use of AC exciter, the residual magnetism in the stator, or permanent magnet (with permanent magnet machines) to establish the voltage of the AC voltage from the rectifier by rotating rectifier, into the main generator field winding, the generator to build pressure. Automatic voltage regulator (AVR), the small deviation of the output voltage quickly reduce or increase the excitation current to maintain the generator set voltage is approximately the same.