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1.目前，煤仍然是凝汽式电厂最长用的能源。At present coal is the most common food of a steam power plant.2.为防止人畜触电，高压电一般采用架空线输送。High voltage current is usually carried by overhead wire system so as to prevent living things being electrocuted.3.这座由电子计算机控制的核电站将向全市供电。This nuclear power plant which is computer-controlled will serve the entire city.4.电学与电子学实际上是唯一难以分开的，二者相互渗透，相互联系。Electricity and electronics are really indivisible, each forming part of the other.5.元件技术中起主要作用的是半导体元件。The major contributors in component technology have been in the sosemiconductor components.6.电压，电流和电阻这三个因素是相互关联的。The factors, voltage, current and resistance , are related to each other .7.电动机与发电机就是以磁和电这二者之间的关系为基础的Based upon the relationship between magnetism and electricity are motors and generators8，随着电气工程学的发展，电力能被输送到非常遥远的地方去。With the development of electrical engineering , power can be transmitted over long distance.9每时每刻，能量都在由一种形式变成另一种形式。Every moment of every day, energy is being transformed from one form into another.10.只要知道电压和电流，就能测定电阻。The resistance can be determined provided that the voltage and current are known.11.已经证明，能量是不可能消灭的，只能转换成其他形式。It has been proved that energy cant be destroyed , it can only be changed into other forms.12。可见磁性材料广泛用于现在电子设备中。It can be seen that magnetic materials are used in a wide range of modern electronic equipment.13.在热电厂燃烧的化学能并未全部转变成热能。In a thermal power plant , all the chemical energy of the fuel is not converted into heat .14.电流过导线就像水流过管子一样。The flowing of electricity through a wire is not unlike that of water through a pipe.15.没有检查好仪表，切勿开始做实验。Never start to do the experiment before you have checked the meter16同性电荷相斥，异性电荷相吸Like charges repel each other while opposite charges attract。17发展经济必须注意环境保护Attention must be paid to environmental protection in developing economy18nothing in the world moves faster than light19自动化能帮助我们提高产量30%Automation will help us to raise the output of production by thirty percent20只要知道电压、电流、就能测定电阻The resistance can be determined provided that the voltage and current are known1.(A temperature transducer ) is a device that a voltage or a current proportional to the actual temperature.2.when the speed of the rotor is zero, the ship of induction machine is (1.0).3.copper losses are(resistive) losses in the primary and secondary windings of the transformer core.4.residential and commercial customers are supplied by the secondary distribution feeders of (220/380v).5.the frequency of a power system is determined mainly by (active power generation and consumption).1.many electrical signals derived from physical systems are obtained from devices called (transducers).2.the air-blast circuit breaker makes use the arc-quenching properties of (dry and clean compressed air).3.in a computer, most processing take place in a computer called the (CPU).1.the difference between a potential transformer and a power transformer is that potential transformer is designed to handle only a very small current.电压互感器与电力变压器的区别在于电压互感器被设计为只能处理很小的电流。1.可是尽管电压表与电流表之间有这些类似之处，但还有若干重要的差异。However, in spite of all this similarity between a voltmeter and an ammeter there are also important difference.2.在电压相同的情况下，导线的电阻越大，流过的电流就越小。The greater the resistance of a wire, the less electric current will pass through it under the same pressure.3.利用发电机，可将机械能再转变成电能。The mechanical energy can be changed back into electrical energy by means of a generator.4、如果实用变压器，低电压的电力就能抓转换成高电压的电力Using a transformer ，power at low voltage can be transformed into power at high voltage1. It is conventional to take the current flow as the movement of (positive charges)2. Electric current is the time rate of charge, measured in (amperes).3. The energy required to move a unit charge through an element is (voltage).4. The plus (+) and minus (-) signs in an electric circuit diagram are used to define (voltage polarity).5. According to the passive sign convention, if the power has a plus sign, power is (absorbed) by the element.1. An independent voltage source is a (two-terminal element), which maintains a specified voltage between its terminals.2. Resistors are (passive) elements.3. An ideal dependent source is an (active) element in which the source quantity is controlled by another voltage or current.4. There are (four) possible types of dependent sources.5. For a voltage source, its terminal voltage is known but its (current) must be determined by the external circuit connecting with it1. The voltage produced by a thermocouple pair is (an analog) signal.2. ON-OFF information can be represented by (a digital) signal.3. A device that can convert an analog signal to the corresponding digital form is called (A/D)for short.4. The thermocouple pair converts temperature difference to a(voltage).5. A D/A is a device that can convert a digital signal to the equivalent (analog form).1. The process of quantizing the continuous values into a binary scale is called (analog-to-digital conversion).2. (A temperature transducer)is a device that produces a voltage or a current proportional to the actual temperature.3. The precision and the speed of an ADC are essentially (incompatible).4. The precision of ADC is determined by (the number of binary bits).5. In Fig.2-4the amplifier performs (two) functions.1. The thumb is in the direction of (the relative motion of conductor)in Flemings right-hand rule.2. In induction motors the speed of the rotating rotor (never reaches)the speed of the rotating magnetic field.3. When the speed of the rotor is zero, the slip of induction machine is (1.0).4. Form-wound coils are widely used for (large AC) motors.4-4(P84)1. A transformer is a device that can converter one ac voltage to another ac voltage through the action of (a magnetic field).2. The primary winding is connected to (the power source).3. The core construction consisting of a three-legged laminated core with the windings wrapped around the centre leg is called (shell form).4. The transformer that takes the distribution voltage and steps it down to the final voltage at which the power is actually used is called a (distribution transformer).5. Copper losses are (resistive) losses in the primary and secondary windings of the transformer core.5-1(P89)1. A computer works automatically according to (a series of stored instructions)2. A keyboard or a mouse is (an input) device.3. The computer network for a university is usually described as (a local area network).4. A computer that requests data from a server is called as (client).5. A hard disk is referred to as (a storage) device.5-4(P108)1. (A support module) can be used in conjunction with the main software program to provide an auxiliary set instructions.2. A computers microprocessor only understands (machine language).3. Delphi belongs to (high-level programming language).4. An operating system is considered as (system software).5. (The file management system) allocates and manages secondary storage space and translates file requests from their name-based form into specific I/O requests.6-1(P118)1. The first complete power system was built in (1882), it was (a DC) power system.2. The first three-phase AC transmission line in North America was put into operation in (1893).3. Power system interconnections are usually formed at the (transmission system) level.4. In North American (60Hz) is adopted as standard frequency in electric power system.5. (The HVDC transmission) can provide an asynchronous link between two ac electric power systems with different nominal frequencies.6-2(P122)1. In power plants (prime movers) convert the primary energy to mechanical energy, and (synchronous generators) convert mechanical energy to electric energy.2. The generator voltages are usually stepped up to the transmission voltage level by (step-up transformers)3. Residential and commercial customers are supplied by the secondary distribution feeders at (220/380V).4. In USA, the voltages of the transmission system are typically (230kV and above)6-3(P130)1. The objective of the optimal economic operation of power systems is (to minimize the total production cost).2. The frequency of a power system is determined mainly by (active power generation and consumption).3. The voltage levels at the terminals of generators are controlled mainly by (automatic voltage regulators).4. When the system frequency is changed away from the rating, (active power) must be regulated.5. Regulation of the generators speed governor can change its (active power) output.7-2(P148)1. At the fault point in electrical equipment, there may be (all of the above).2. Among the following faults on a transmission line, the most severe one is usually the (3-0 fault).3. Among the following faults on a transmission line, the most common one is the (single line to ground fault).4. The most common fault in the generators stator winding is (phase to ground fault).5. If generator overspeed occurs in a thermal power plant, the action most possibly undertaken is (to shut off the steam).7-3(P152)1. The use of transformer oil in a minimum-oil circuit breaker is (to quench the arc and establish an insulated break between the contacts)2. A circuit breaker mainly consists of (three) parts.3. The air-blast circuit breaker makes use the arc-quenching properties of (dry and clean compressed air).4. The reason that the SF6 circuit breaker is widely used is (the excellent arc quenching and insulating).5. Vacuum-bottle interrupters are designed for (higher system voltage, current).8-2(P171)1. In hydropower plants, (Francis turbines) are frequently used for medium heads.2. During times of the off-peak load, a pumped-storage plant should (absorb energy from the power network),3. The overall efficiency of a pumped storage plant is usually about (65%70%).4. The start-up speed of a hydropower plant is (faster than) that of a thermal plant.5. The hydropower is well suited for switching according to (a dispatchers) an operators
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