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柴油发电机组技术术语

 

 

AC
Alternating Current (AC) is electric current that alternates between a positive maximum value and a negative maximum value at a characteristic frequency, usually 50 or 60 cycles per second (Hertz).
交流
交流是指电流在正负最大值之间以特定的频率变动,通常频率为50或60赫兹。我国工频为50Hz
Active Power
Active power is the real power (kW) supplied by the generator set to the electrical load. Active power creates a load on the generator set's engine and is limited by the horsepower of the engine. Active power does the work of heating, turning motor shafts, etc.
有功功率
有功功率(kW),是指发电机组实际供应给负载的功率,它由发电机的发动机提供,受到发动机马力大小的限制。发热和驱动马达转动靠有功功率完成
Amortisseur Windings
The amortisseur windings of a synchronous AC generator are the conductors embedded in the pole faces of the rotor. They are connected together at both ends of the poles by end rings or end plates. Their function is to dampen waveform distortion during load changes.
阻尼线圈
同步交流发电机的阻尼线圈是指嵌绕在转子磁极间的导线,他们分别在两极用端环或端板相连接,主要功能是减弱因负载变化而引起的波形畸变
Ampacity
Ampacity is the safe current-carrying capacity of an electrical conductor in amperes as defined by code.
载流容量
载流容量是以安培数来定义导线安全载流能力
Ampere
The ampere is a unit of electric current flow. One ampere of current will flow when a potential of one volt is applied across a resistance of one ohm.
安培
安培是电流单位。1伏电压作用于1欧姆的电阻上就会产生1安培的电流
Apparent Power
Apparent power is the product of current and voltage, expressed as kVA. It is real power (kW) divided by the power factor (PF).
视在功率
视在功率是电流和电压共同作用的产物,用kVA表示。它等于有功功率(kW)除以功率因数
Armature
The armature of an AC generator is the assembly of windings and metal core laminations in which the output voltage is induced. It is the stationary part (stator) in a revolving-field generator.
电枢
交流发电机电枢的是金属芯和绕组的总成,产生感应电压。电枢是旋转磁场交流发电机的不动部分(定子)
B
Base Load
Base load is that portion of a building load demand which is constant. It is the "base" of the building demand curve.
基本负荷
基本负荷是指建筑负荷需求量中不变的那一部分, 是构成负荷需求曲线的基数
Black Start
Black Start refers to the starting of a power system with its own power sources, without the assistance from external power supplies.
黑启动?
黑启动是指依靠系统内部的电源,而不借助外部的电力进行的启动
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C
CT (Current Transformer)
Current transformers are instrument transformers used in conjunction with ammeters, control circuits and protective relaying. They usually have 5 ampere secondaries.
电流互感器
电流互感器是一种仪表变压器,通常与电流表、控制电路、保护继电器配套使用
Circuit
A circuit is a path for an electric current across a potential (voltage).
电路
电路是电流通过电势(电压)的路径
Circuit Breaker
A circuit breaker is a protective device that automatically interrupts the current flowing through it when that current exceeds a certain value for a specified period of time. See Air Circuit Breaker, Main Breaker, Molded Case Circuit Breaker and Power Circuit Breaker.
断路器?
线路断路器是一个保护装置,当通过它的电流超过某个安全设定值一定时间后,它就能够自动切断电流。(见空气线路断路器、主开关、塑壳线路断路器等)
Circulating Harmonic Currents
Circulating Harmonic Currents are currents that flow because of differences in voltage waveforms between paralleled power sources, or induced by operation of non-linear loads.?
谐波环流
谐波环流是由并联电源间不同的电压波形或者非线性负荷运转而产生的电流
Continuous Load
A continuous load is a load where the maximum current is expected to continue for three hours or more (as defined by the NEC for design calculations).
持续负荷
持续负荷是指使电流在3个小时或更长时间(根据NEC的定义)内需保持最大值的负荷
Current
Current is the flow of electric charge. Its unit of measure is the ampere.
电流
电流是电荷的流动,以安培为单位
Cycle
A cycle is one complete reversal of an alternating current or voltage from zero to a positive maximum to zero again and then from zero to a negative maximum to zero again. The number of cycles per second is the frequency.
周期
周期是指交流电流或电压从零到正最大值再到零,然后从零到负最大值再到零这样一个往复的过程;而频率则是指每秒可完成的周期数
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D
Delta Connection
Delta connection refers to a three phase connection in which the start of each phase is connected to the end of the next phase, forming the triangle-shaped Greek letter Delta. The load lines are connected to the corners of the triangle.
三角形连接
三角形连接是指在三相连接中,相临两相首尾相连,构成三角形的希腊字母Delta,负荷线连接在三角形的角上
Differential Relay
A differential relay is a protective device that is fed by current transformers located at two different series points in the electrical system. The differential relay compares the currents and picks up when there is a difference in the two, which signifies a fault in the zone of protection. These devices are typically used to protect windings in generators or transformers.
差动继电器
作为保护装置,差动继电器由位于系统中两个不同位置的电流互感器提供反馈信息。差动继电器对电流进行比较,如果存在不同则表示受保护区域内有故障存在。这些装置常被用于保护发电机或变压器的线圈
Digital Master Control (DMC)
This device is designed to control the power systems in a facility. It is offered as an option on Cummins switchgear.?
数字主控制器?
数字主控制器是用于控制设备电力系统的装置。在康明斯开关柜中数字主控制器是选配件
Direct Current (DC)
Direct current is current with no reversals in polarity.
直流
直流是指没有正负极性往复变化的电流
Droop Load Sharing
Droop load sharing is a method of making two or more parallel generator sets share a system kW load. This is accomplished by having each governor control adjusted so that the sets have the same droop (reduction of speed). Typical droop is two cycles in frequency from no load to full load.
转速降负荷分配
转速降负荷分配是两台或多台
E
Efficiency (EFF)
Efficiency is the ratio of energy output to energy input, such as the ratio between the electrical energy input to a motor and the mechanical energy output at the shaft of the motor.
效率
效率是输出能量与输入能量的比率,例如输入到电动机的电能与电机轴承输出的机械能的之间的比率
Emergency System
An emergency system is independent power generation equipment that is legally required to feed equipment or systems whose failure may present a life safety hazard to persons or property.
应急系统
应急系统是指根据相关法规要求,为那些可能会危及生命安全或造成财产重大损失的设备或系统提供电源的独立发电设备
Energy
Energy is manifest in forms such as electricity, heat, light and the capacity to do work. It is convertible from one form to another, such as in a generator set, which converts rotating mechanical energy into electrical energy. Typical units of energy are kW/h, Btu (British thermal unit), Hp/h, ft/lbf, joule and calorie.
能量
能量以电能、热能、光能等形式存在,可以做功,也可以从一种形式转换为另一种形式,例如发电机组能把机械能转变为电能。经常用的能量单位有: 千瓦/小时、英国热量单位、马力/小时、焦耳、卡等
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F
Fault
A fault is any unintended flow of current outside its intended circuit path in an electrical system.?
故障
故障是指在电力系统中任何电流跑出正常电路以外的情况
Frequency
Frequency is the number of complete cycles per unit of time of any periodically varying quantity, such as alternating voltage or current. It is usually expressed as (Hz) Hertz or CPS (cycles per second).
频率
频率是指周期性变化的事物(如交流电压和电流等)在单位时间内完成的周期数,常用单位是赫兹(Hz)或周期/秒(CPS)??
Frequency Adjust Potentiometer
A frequency adjust potentiometer is used to manually bring the frequency (speed) of the incoming set to that of the bus for synchronizing purposes. When the generator set is paralleled, operation of this potentiometer will adjust the kW load assumed by the generator set.
频率调整电位器
频率调整电位器是用于手动调整输入机组的频率使之与母排同步。当机组并联后,电位器可以调整为机组输出功率值
Frequency Regulation
Frequency regulation is a measure that states the difference between no-load and full-load frequency as a percentage of full-load frequency.?
频率调整率
频率调整率是指空载和满载之间频率的差别与满载频率的百分比
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G
Generator
A generator is a machine which converts rotating mechanical energy into electrical energy
发电机
发电机是把(旋转)机械能转化为电能的装置
Governor
A governor is a device on the engine which controls fuel to maintain a constant engine speed under various load conditions. The governor must have provision for adjusting speed (generator frequency) and speed droop (no load to full load).
调速器
调速器是安装在发动机上的一个装置,在不同的负载条件下通过控制燃料量来保持发动机的恒定转速。调速器必须具备转速调整(发电机频率)和降速降调整(零负荷到满负荷)功能
Grid
The utility-owned power distribution system.
电网
电网是指电厂的电力输送系统
Ground
A ground is a connection, either intentional or accidental, between an electrical circuit and the earth or some conducting body serving in place of the earth.?
接地
接地是电路与地面或地面上的导体的连接,可以是有意的也可以是意外的?
Ground Fault Protection
This function trips (opens) a circuit breaker or sounds an alarm in the event that there is an electrical fault between one or more of the phase conductors and ground (earth). This ground fault protection function may be incorporated into a circuit breaker.?
接地故障保护
当一个或多个相导线与地之间出现电气故障时,接地故障保护通过跳脱断路器或报警来示警。这种功能可以一体化设计在断路器上
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H
Hertz (Hz)
The term Hertz is the preferred designation for cycles per second (CPS) and is used to describe frequency
赫兹
赫兹是频率单位,也等于周期/秒(CPS)
Hunting
Hunting is a phenomenon that can occur upon load changes in which the frequency or the voltage continues to rise above and fall below the desired value without reaching a steady-state value. It is caused by insufficient damping
游车
游车是一种在负载变化引起的频率、电压高于或低于期望值,无法达到稳定的现象。它是由于阻尼不足而造成的
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I
Insulation
Insulation is non-conductive material used to prevent leakage of electric current from a conductor. There are several classes of insulation in use for generator construction, each recognized for a maximum continuous-duty temperature.?
绝缘
绝缘体就是非导电材料,用来防止导体中电流的泄露。按最高持续耐热度划分,发电设备中使用的绝缘体有多种等级
L
Lagging Power Factor
Lagging power factor in AC circuits (a power factor of less than 1.0) is caused by inductive loads, such as motors and transformers, which cause the current to lag behind the voltage. See Power Factor
滞后功率因数
交流电路中的滞后功率因数(小于1.0)是由感应负荷引起的,例如发动机、变压器,使电流滞后于电压。(参照功率因数)
Leading Power Factor
Leading power factor in AC circuits (0.0 to -1.0) is caused by capacitive loads or overexcited synchronous motors which cause the current to lead the voltage. See Power Factor
超前功率因数
交流电路中的超前功率因数(0.0 to -1.0)是由电容负荷或者过励的同步电动机引起的,使电流超前于电压。(参照功率因数
Line-To-Line Voltage
Line-to-line voltage is the voltage between any two phases of an AC generator
线电压
线电压是指交流发电机任何两相间的电压
Line-To-Neutral Voltage
In a 3-phase, 4-wire, Y-connected generator, line-to-neutral voltage is the voltage between a phase and the common neutral where the three phases are tied together
在三相四线星形连接的发电机中,相电压是指三相连接点与每相之间的电压
Load Factor
The load factor is the ratio of the average load to the generator set power rating
负荷系数
负荷系数指的是机组的平均负荷与额定功率之间的比率
Load Shedding
Load shedding is the process by which the total load on a paralleling system is reduced, on overload of the system bus, so that the most critical loads continue to be provided with reliable electrical service
卸载
在超载的系统母排上,并联系统的总负载被降低的过程称为卸载,以确保最关键负载获得可靠的电力供应
Low Voltage
AC system operating voltages from 120 to 600 VAC
低压
M
Main Breaker
A main breaker is a circuit breaker at the input or output of the bus, through which all of the bus power must flow. The generator main breaker is the device, usually mounted on the generator set, that interrupts the genset's power output. Main breakers provide overcurrent protection and a single disconnect point for all power in a switchboard or device
主开关
主开关是母排输入或输出端的线路断路器,所有的电流都要从那通过。主开关通常安装在发电机组上,用来切断输出电流。主开关能够提供过电流保护,是配电盘或设备的电源断开点
Mains
Mains is a term used extensively outside of the United States to describe the normal power service (utility)
市电?
市电是美国以外的区域对常规电力服务的广泛称谓
Master Control
A control section in a typical paralleling system that provides total system metering and the interface point between the paralleling system and the facility
主控制
主控制是典型的并联系统计量控制设备,也是并联系统与用电设施之间的接口
AC system operating voltages from 601 to 15000 VAC
中压
交流电系统中从601 到15000 VAC的电压称为中压
Modbus “专用名词
An industrial networking system that uses RS-232 serial master-slave communications at data transfer rate of up to 19.2 KBPS
一种工业网络,它使用RS232主从通讯模式传输数据,最快可达19.2kBPS
Modules
Modules are also called nodes or devices. These are devices such as Genset Communication Modules (GCMs), Control Communication Modules (CCMs), and Digital Input/Output Modules (DIMs)
模块也可以称作接点或组件,例如机组通讯模块(GCMs)、控制通讯模块(CCMs)以及数字输入/输出模块(DIMs)
Molded Case Circuit Breaker
A molded case circuit breaker automatically interrupts the current flowing through it when the current exceeds the trip rating of the breaker. Molded case refers to the use of molded plastic as the medium of electrical insulation for enclosing the mechanisms, and for separating conducting surfaces from one another and from grounded (earthed) metal parts. Molded case circuit breakers usually contain thermal-magnetic trip units, although larger sizes can be equipped with solid state trip sensors
塑壳断路器
塑壳断路器能够自动切断电流在电流超过跳脱设定后。塑壳指的是用塑料绝缘体来作为装置的外壳,用来隔离导体之间以及接地金属部分。塑壳断路器通常含有热磁跳脱单元,而大型号的塑壳断路器会配备固态跳脱传感器
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N?
Network
A collection of Nodes that communicate with one another over a common medium
网络?
在共同的介质上互相通讯的接点的集合就是网络
Neutral Current
Neutral current is the current that flows in the neutral leg of a paralleling system. Often, this term is used in reference to circulating currents or cross currents
零线电流
零线电流指的是通过并联系统零线的电流,在谈及环流电流或者交叉电流时常会提到这个术语
Nonlinear Load
A nonlinear load is a load for which the relationship between voltage and current is not a linear function. Some common nonlinear loads are fluorescent lighting, SCR motor starters and UPS systems. Nonlinear loads cause abnormal conductor heating and voltage distortion
非线性负载
电压和电流之间是非线性关系的负载称为非性形负载。一些常见的非线性负载有荧光灯、可控硅电动机启动器以及UPS系统。非线性负载能导致反常的导体发热和电压畸变
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?O
Ohm
The ohm is a unit of electrical resistance. One volt will cause a current of one ampere to flow through a resistance of one ohm.?
欧姆 欧姆是电阻单位。1伏特的电压通过1欧姆的电阻能产生1安培的电流
One-Line Diagram
A one-line diagram is a schematic diagram of a three-phase power distribution system which uses one line to show all three phases. It is understood when using this easy to read drawing that one line represents three.?
单线图
单线图是用一条线来表示三相电力分布系统的示意
Overcrank
Overcrank is an alarm function provided with most generator sets that indicate that the generator set has failed to start.?
盘车失败
盘车失败是机组的预警功能,表示发电机组启动失败,大多数机组都有这种功能?
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?P
Paralleling Breaker
A paralleling breaker is the circuit breaker that connects the generator set to the emergency bus, and across which all the individual generator synchronizing functions occur.
并联开关
并联开关是连接发电机组和应急母排的线路断路器,所有的单个发电机通过它完成同步运行
Paralleling Control
A paralleling control contains the electrical equipment provided in a paralleling system for control of a single generator set.
并联控制
并联控制是并联系统中用来控制单个发电机组的电气设备
Phase Angle
Phase angle refers to the relation between two sine waves which do not pass through zero at the same time. Considering one full cycle to be 360 degrees, the phase angle expresses how far apart the two waves are in relation to each other in degrees.?
相角?
相角指的是两个不同时经过零点的正弦波之间的关系。一个完整周期为360度,相角就是用度数来表示两个波的距离
Phase Rotation
Phase rotation (or phase sequence) describes the order (A-B-C, R-S-T, or U-V-W) of the phase voltages at the output terminals of a three-phase generator. The generator phase rotation must match the facility phase rotation. This must be checked prior to operation of the electrical loads in a facility with an on-site generator.?
相序?
相序表示的是三相发电机输出终端相电压的顺序。在用电负载运转之前必须检查确保发电机的相序与用电设施的相序一致?
Port
The external connector on a device at which the network cable or medium is attached.
接口
设备的外接口,用于连接网络线或者其它介质
Power Factor
Power factor is the cosine of the angle between the active power (kW) and apparent power (kVA) in a circuit.?
功率因数
功率因数是电路中有功功率(kW)和视在功率(kVA)之间夹角的余弦值
Prime Power
Prime Power describes an application where the generator set(s) must supply power on a continuous basis and for long periods of time between shutdowns. No utility service is present in typical prime power applications.?
常载
常载是指发电机组可长时间和连续的运行。通常在没有市电供应,发电机组作为首要电源的场合使用
Priority Control
Priority control is the process by which the total loads on the bus is limited to the most critical loads in the system until adequate generation capacity is available to serve all loads.?
优先级控制
优先级控制是指当总负载电力需求大于发电机组的输出时,首先要满足最关键负载的电力需求
Protocol
A set of rules used mutually by two or more devices to communicate. Also, known as the "language" used in a network.?
协议
两个或多个设施共同遵守的一些通讯规则,在网络中常称为“语言”
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?R?
Radio
Interference Radio interference refers to the interference with radio reception caused by a generator set.
无线电干扰
无线电干扰是指发电机组对无线电信号接收造成的干扰
Reactive Power
Reactive power is power that flows back and forth between the inductive windings of the generator and the inductive windings of motors, transformers, etc., which are part of the electrical load. This power does no useful work in the electrical load nor does it present load to the engine. It does apply load to the generator and limits the capacity of the generator.?
无功功率
无功功率是指电流在发电机、电动机、变压器等的感应线圈之间往复流动,这也构成了电力负载的一部分。它并没做有用功,而且也不是发动机的负载,但是作为发电机负载,限制了发电机的容量
Reverse Power
Relay A reverse power relay is a relay with a wattmeter movement that senses the direction of power flow. In paralleled sets, a flow of reverse power (i.e., power flow into set) will actuate the reverse power relay and disconnect the set from the system. If one set stops and reverse power protection is not provided, the set still running will drive the set that has stopped. The generator on the set that has stopped will act as a motor.?
逆功率继电器
逆功率继电器是指带瓦特计的继电器,用来感知电流的方向。在并联机组中,反方向电流(例如流回发电机组的电流)会启动逆功率继电器,把该机组与系统断开。如果一台发电机组没有运转,并且没有逆功率继电器保护,运转的机组就会驱动这个机组,这台机组上的发电机则变成电动机运行
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S
SCR
Silicon Controlled Rectifier -- a three-electrode solid-state device which permits current to flow in one direction only, and does this only when a suitable potential is applied to the third electrode, called the gate.?
可控硅整流器
可控硅整流器——三电极固态元件,只有当匹配的电压作用于第三电极(选通电极)时,才能够保证电流朝一个方向流动
Short Circuit
A short circuit is generally an unintended electrical connection between current carrying parts.?
短路?
短路通常是指带电流的组件之间意外的电路连接
Shunt Trip
Shunt trip is a feature added to a circuit breaker or fusible switch to permit the remote opening of the breaker or switch by an electrical signal.
分励脱扣
分励脱扣是线路断路器或可熔电闸的一个特性,可通过远程信号来进行分断或转换
Soft Loading
Soft loading refers to the ramping of load onto or off of a generator in a gradual fashion for the purpose of minimizing voltage and frequency transients on the system.?
软加载
软加载是指在给发电机组增加或减少负载时要逐渐进行,以减少电压和频率对系统的瞬变影响
Sound Level
Meter A sound level meter measures sound pressure level. It has several frequency-weighted decibel (dB) scales (A, B, C) to cover different portions of the range of measured loudness. Sound level meters indicate RMS sound, unless the measurements are qualified as instantaneous or peak sound level.?
声级表
声级表是用来测量声压级别的,它根据声音的频率分为几个分贝级(A, B, C)。声级表表征的是均方根声音,除非是适合瞬间或峰值的度量
Sound Pressure Level (SPL)
Sound pressure level is a measurement of the pressure fluctuations of a sound wave as it propagates through the air. Because of the wide range of pressures to which the ear responds, a logarithmic scale is used and is expressed as a ratio of the measured pressure referenced to a pressure of 2x10-5 N/m2 (20 m Pa) which is the threshold of human hearing at 1000 Hz. The measure is expressed in decibels (dB). The Bel unit is named after Alexander Graham Bell.
声压级别?
声压级别是表示在空气中传播的声波的起伏压。由于耳朵能感知的声压范围很大,所以采用其对数值,并以2x10-5 N/m2 (20 m Pa)的比率表示,这是人类在1000 Hz所能听到的极限,单位是分贝(dB)。贝尔(十分贝)是以亚历山大·格雷姆·贝尔的名字命名的
Standby System
A standby system is an independent power system that allows operation of a facility in the event of normal power failure.?
备用系统
备用系统是一个独立的电力供应系统,当常规电力供应失败时,备用系统就会运行
Star Connection
See Wye Connection.?
星形连接
参见Y形连接
Starting Current
The initial value of current drawn by a motor when it is started from standstill.
启动电流
当发动机从停止状态启动时带来的初始电流值就是启动电流
Surge
Surge is the sudden rise in voltage in a system, usually caused by load disconnect.?
突变
突变是指系统中电压突然升高,通常是由于负载断开而引起的
Sync Check Relay
A sync check relay is an electrical device that monitors the phase relationship between two voltage sources and provides a signal when the voltage sources are within specific preset parameters.?
同步检查继电器
同步检查继电器是监测两个电压源之间的相位关系的电气设备,如果电压源间的关系在预定的参数范围内,它就会发出相应信号
Synchronizer
A synchronizer is an electronic device that monitors the phase relationship between two voltage sources and provides a connection signal to an engine governor, to force the generator set to synchronize to the system bus.
同步器
同步器是用来监测两个电压源之间的相位关系的电子设备,它向发动机调速器发出信号,以促使发电机组与系统母排能够同步
Synchronous Generator
A synchronous generator is an AC generator having a DC exciter. Synchronous generators are used as stand-alone generators for emergency power and can also be paralleled with other synchronous generators and the utility system.
同步发电机
同步发动机是配有直流励磁机的同步交流发电机。同步发动机能作为独立的紧急电源,也可以与其他同步发电机或市电并联。 ?
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?T
Transfer Switch
A transfer switch is an electrical device for switching loads between alternate power sources. An automatic transfer switch monitors the condition of the sources and connects the load to the alternate source if the preferred source fails.
转换开关
转换开关是能够把负载在备用电源和常规电源之间进行转换的电气设施。自动转换开关能够进行监控,如果首选电源供应失败,就自动把负载连接到备用电源
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U
Utility
The utility is a commercial power source that supplies electrical power to specific facilities from a large central power plant.
市电?
市电是商业电源,从大型中央电站向各设施供电
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?V
Voltage Dip
Voltage dip is the dip in voltage that results when a load is added, occurring before the regulator can correct it, or resulting from the functioning of the voltage regulator to unload an overloaded engine-generator.
电压暂降
电压暂降是在负荷增加而调整器还未能进行校正时、或电压调整器正在为过载的发动机卸载时出现的电压下降
VoltageRegulation
Voltage regulation is a measure that states the difference between maximum and minimum steady-state voltage as a percentage of nominal voltage.
电压调整率
电压调整率描述的是最大和最小稳态电压差与额定电压之间的百分比
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W
Watt-Hour Mete
A watt-hour meter records the total power output at a specific point in a system. Typical recording increment is in kW-hours.
电度表
电度表记录系统中某一点的总电力输出,通常以千瓦时为记录单位
Wye Connections
A Wye connection is the same as a star connection. It is a method of interconnecting the phases of a three-phase system to form a configuration resembling the letter Y. A fourth (neutral) wire can be connected at the center point.?
Y连接
Y连接就是星形连接,也就是把三相系统中的相按照字母Y的形状连接起来,还可以在中心点接上第四根(中性)线
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?Z?
Zero Sequenc
Zero sequence is a method of ground fault detection that utilizes a sensor (CT) that encircles all the phase conductors as well as the neutral conductors. The sensor will produce an output proportional to the imbalance of ground fault current in the circuit. This output is then measured by a relay to initiate circuit breaker tripping or ground fault alarm.
零序
零序是一种接地故障检测方法,它使用一个传感器(CT)来把所有相导体和中性导体连接在一起,传感器会按照线路中接地故障电流的不平衡程度等比例地产生输出,再由一台继电器来测量这一输出,并断开断路器或释放接地故障警报
柴油发动机
柴油机是内燃机的一种类型,是一种将燃料燃烧释放出来的热能转变为机械能的能量转换装置。柴油机是发电机组的动力部分,一般由曲轴连杆机构与机体组件、配气机构与进排气系统、柴油供给系统、润滑系统、冷却系统和电气系统等组成
工作循环
内燃机中热能与机械能的转化,是通过活塞在气缸内工作,连续进行进气、压缩、做功、排气四个过程来完成的。机器每进行这样一个过程称为一个工作循环
上止点和下止点
当活塞在气缸中移动时,活塞顶处在气缸中的最高位置称为上止点(或称上死点);活塞顶在气缸中的最低位置,称为下止点(或称下死点)
活塞冲程
上、下止点之间的最小直线距离称为活塞冲程(或称行程),通常用S表示。曲轴与连杆大端的连接中心到曲轴的旋转中心之间的最小直线距离称为曲柄的旋转半径
工作容积
活塞从上止点到下止点所扫过的气缸容积,称为气缸工作容积(或称活塞排量)
压缩比
新鲜气体吸入气缸后充满了整个气缸,即占有气缸总容积,而气缸总容积则包括燃烧室容积和气缸的工作容积。压缩比的大小,说明气缸内的空气(或混合气)经压缩后体积缩小的倍数,也表明气体被压缩的程度。压缩比越大,表明活塞运动时,气体被压缩得越厉害,其气体的温度和压力就越高,内燃机的效率也越高。
进气冲程
进气冲程的目的是吸入新鲜空气,为燃料燃烧作好准备。要实现进气,缸内与缸外要形成压差。因此,此冲程排气门关闭,进气门打开,活塞由上止点向下止点移动,活塞上方的气缸内的容积逐渐扩大,压力降低,缸内气体压力低于大气压力约68~93kPa。在大气压力的作用下,新鲜空气经进气门被吸入气缸,活塞到达下止点时,进气门关闭,进气冲程结束。
压缩冲程
压缩冲程的目的是提高气缸内空气的压力和温度,为燃料燃烧创造条件。由于进、排气门都已关闭,气缸内的空气被压缩,压力和温度亦随之升高,其升高的程度,取决于被压缩的程度,不同的柴油机略有不同。当活塞接近上止点时,缸内空气压力达(3000~5000)kPa ,温度达500~700℃,远超过柴油的自燃温度。
膨胀(做功)冲程
当活塞上行将终了时,喷油器开始将柴油喷入气缸,与空气混合成可燃混合气,并立即自燃,此时,气缸内的压力迅速上升到约6000~9000kPa,温度高达(1800~2200)℃。在高温、高压气体的推力作用下,活塞向下止点运动并带动曲轴旋转而做功。随着气体膨胀活塞下行其压力逐渐降低,直到排气门被打开为止。
排气冲程
排气冲程的目的是清除缸内的废气。做功冲程结束后,缸内的燃气已成为废气,其温度下降到(800~900)℃,压力下降到(294~392)kPa。此时,排气门打开,进气门仍关闭,活塞从下止点向上止点移动,在缸内残存压力和活塞推力的作用下,废气被排出缸外。当活塞又到上止点时,排气过程结束。排气过程结束后,排气门关闭,进气门又打开,重复进行下一个循环,周而复始不断对外做功。
调速器
调速器的作用是在柴油机工作转速范围内,能随着柴油机外界负荷的变化而自动调节供油量,以保持柴油机转速基本稳定

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