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RƯỜNG ĐẠI HỌC ĐIỆN LỰC KHOA ĐIỀU KHIỂN & TỰ ĐỘNG HĨA BÁO CÁO CHUN ĐỀ NGÀNH: Cơng nghệ kỹ thuật điều khiển tự động hóa CHUYÊN NGÀNH: Tự động hóa điều khiển thiết bị cơng nghiệp HỌC PHẦN: Tiếng Anh chuyên ngành Giảng viên hướng dẫn: Nguyễn Ngọc Khốt Nhóm sinh viên/ sinh viên thực – Mã sinh viên: Nhóm : Nguyễn Khánh Hùng Khơi - 19810430152 Trần Lâm Hải Long - 19810430211 Lê Hoàng Minh - 19810430138 Trần Anh Thắng - 19810430273 Lớp : D14TDH&DKTBCN3 HÀ NỘI, 2/2022 Đề tài nhóm 3: Tiếng Anh Chuyên Ngành Chương 1: Introduction to power sources (DC and AC power) 1.1 Definition 1.2 How to use power sources in an electrical circuit? 1.3 How to produce power sources? 1.4 How internal resistance of power sources affects operation of an electrical circuit? 1.5 Ohm’s law of an electrical circuit regarding power sources 1.6 Applications of power sources Chương 2: Synchronous AC motors 2.1 Concept 2.2 Classification 2.3 Structure 2.4 Working principle 2.5 Speed control methods for the synchronous AC motors 2.6 Applications Chương 3: Introduction to PLC Mitsubishi 3.1 What is PLC? 3.2 What are differences between PLC and traditional relay circuits? 3.3 Select and present briefly a PLC of Mitsubishi Nguyễn Khánh Hùng Khôi 19810430152 Tiếng Anh Chuyên Ngành LỜI CẢM ƠN Trong thời gian làm báo cáo chuyên đề, em nhận nhiều giúp đỡ, đóng góp ý kiến bảo nhiệt tình thầy cô bạn bè Em xin gửi lời cảm ơn chân thành đến thầy Nguyễn Ngọc Khoát, giảng vên người tận tình hướng dẫn, bảo em suốt trình làm chuyên đề điều khiển số Em xin chân thành cảm ơn thầy cô giáo trường Đại học Điện Lực nói chung, thầy mơn điện tử cơng suất nói riêng hướng dẫn cho em kiến thức cách trình bày nội dung đồ án, giúp em có sở lý thuyêt tạo điều kiện gúp đỡ em trình làm báo cáo chuyên đề Tuy vậy, với kinh nghiệm kiến thức cịn thiếu sót nên báo cáo chun đề em cịn chưa hồn thiện lắm, em mong sử dẫn chân thành thầy cô Cuối cùng, em xin chân thành cảm ơn thầy cô bạn bè tạo kiện, quan tâm, giúp đỡ em suốt trình học tập hồn thành báo cáo Nguyễn Khánh Hùng Khôi 19810430152 Tiếng Anh Chuyên Ngành Chương 1: Introduction to power sources (DC and AC power) 1.1 Definition Alternating current power is the standard electricity that comes out of power outlets and is defined as a flow of charge that exhibits a periodic change in direction AC's current flow changes between positive and negative because of electronselectrical currents come from the flow of these electrons, which can move in either a positive (upward) or negative (downward) direction This is known as the sinusoidal AC wave, and this wave is caused when alternators at power plants create AC power Alternators create AC power by spinning a wire loop inside a magnetic field Waves of alternating current are made when the wire moves into areas of different magnetic polarity—for example, the current changes direction when the wire spins from one of the magnetic field's poles to the other This wave-like motion means that AC power can travel farther than DC power, a huge advantage when it comes to delivering power to consumers via power outlets Direct current (DC) power, as you may guess from the name, is a linear electrical current—it moves in a straight line Direct current can come from multiple sources, including batteries, solar cells, fuel cells, and some modified alternators DC power can also be "made" from AC power by using a rectifier that converts AC to DC DC power is far more consistent in terms of voltage delivery, meaning that most electronics rely on it and use DC power sources such as batteries Electronic devices can also convert AC power from outlets to DC power by using a rectifier, often built into a device's power supply A transformer will also be used to raise or lower the voltage to a level appropriate for the device in question 1.2 How to use power sources in an electrical circuit? Power sources two important things: +) They supply energy to the circuit in the form of an electric potential difference +) They provide a source and sink for electrons in a circuit As a simple analogy, you can think of a power source as the heart of a circuit; just as our heart circulates blood to enable our bodies to function, electric power sources pump or circulate electrons, enabling electric circuits to function You can think of a power source as a ‘pump’ that keeps electrons flowing in a circuit Without a power source, a circuit will quickly lose energy due to the electrical resistance of its components Power sources are known as active components because they supply energy to the electric circuit Power sources supply electric power by pushing and pulling the electrons in a circuit Without a power source, circuits quickly stop working due to energy losses Think about the battery in your phone or tablet When the battery runs out of charge, it stops functioning as a power source and your device quickly shuts down Power sources are really important because every circuit and component relies on them in order to function We start our discussion on circuits with power sources because they are the beating heart of every circuit Nguyễn Khánh Hùng Khôi 19810430152 Tiếng Anh Chuyên Ngành 1.3 How to produce power sources? The three major categories of energy for electricity generation are fossil fuels (coal, natural gas, and petroleum), nuclear energy, and renewable energy sources Most electricity is generated with steam turbines using fossil fuels, nuclear, biomass, geothermal, and solar thermal energy Other major electricity generation technologies include gas turbines, hydro turbines, wind turbines, and solar photovoltaics 1.4 How internal resistance of power sources affects operation of an electrical circuit? In the case of circuits, the equivalent of ‘friction’ is something called electric resistance Every electric component has some amount of electric resistance Even conductors like wires have some resistance to the movement of electrons That’s because conductors don’t conduct electricity perfectly, and they lose some energy as heat as a result The energy loss quickly causes all the electrons in the circuit to stop moving when disconnected from the power source, even if the circuit remains closed In AC circuits, resistance is called impedance That’s because the total ‘resistance’ to current flow in an AC circuit doesn’t just come from electric resistance Capacitance and inductance also contribute to the overall opposition to current flow in an AC circuit The total opposition to current flow, caused by resistance, capacitance and inductance is called impedance 1.5 Ohm’s law of an electrical circuit regarding power sources The current through a resistor is in direct proportion to the voltage across the resistor's terminals This relationship is represented by Ohm's law: Where I is the current through the conductor in units of amperes, V is the potential difference measured across the conductor in units of volts, and R is the resistance of the conductor in units of ohms (symbol: Ω) 1.6 Applications of power sources For DC  DC current limited by a resistor causes light-emitting diodes (LEDs) to produce light  Mechanical and electronic switches can deliver large amounts of DC control current to motors, solenoids, and resistive heaters  DC currents and voltages establish the electrical conditions that allow transistors to amplify AC signals For AC  Cell phones  Flashlights\  The Lilypad-based D&D Dice Gauntlet  Flat-screen TVs (AC goes into the TV, which is converted to DC)  Hybrid and electric vehicles Nguyễn Khánh Hùng Khôi 19810430152 Tiếng Anh Chuyên Ngành Chương 2: Synchronous AC motors 2.1 Concept A synchronous electric motor is an AC electric motor in which, at steady state, the rotation of the shaft is synchronized with the frequency of the supply current; the rotation period is exactly equal to an integral number of AC cycles Synchronous motors contain multiphase AC electromagnets on the stator of the motor that create a magnetic field which rotates in time with the oscillations of the line current The rotor with permanent magnets or electromagnets turns in step with the stator field at the same rate and as a result, provides the second synchronized rotating magnet field of any AC motor A synchronous motor is termed doubly fed if it is supplied with independently excited multiphase AC electromagnets on both the rotor and stator The synchronous motor and the induction motor are the most widely used types of AC motors The difference between the two types is that the synchronous motor rotates at a rate locked to the line frequency since it does not rely on current induction to produce the rotor's magnetic field By contrast, the induction motor requires slip: the rotor must rotate slightly slower than the AC alternations in order to induce current in the rotor winding Small synchronous motors are used in timing applications such as in synchronous clocks, timers in appliances, tape recorders and precision servomechanisms in which the motor must operate at a precise speed; speed accuracy is that of the power line frequency, which is carefully controlled in large interconnected grid systems Synchronous motors are available in self-excited sub-fractional horsepower sizes to high power industrial sizes In the fractional horsepower range, most synchronous motors are used where precise constant speed is required These Nguyễn Khánh Hùng Khôi 19810430152 Tiếng Anh Chuyên Ngành machines are commonly used in analog electric clocks, timers and other devices where correct time is required In higher power industrial sizes, the synchronous motor provides two important functions First, it is a highly efficient means of converting AC energy to work Second, it can operate at leading or unity power factor and thereby provide power-factor correction 2.2 Classification Synchronous motors are classified according to their speed They are either high-speed or low-speed machines Those operating over 500 RPM are designated high-speed motors Beside speed, synchronous motors can be classified by type There are different types of synchronous motors based on the way they are excited  Non Excited Synchronous Motors  Current Excited Synchronous Motors Non Excited Synchronous Motor The rotor is made up of steel The external magnetic field magnetizes the rotor, and it rotates in synchronism with it The rotor is generally made of high retentivity steel such as cobalt steel Non-excited motors are available in three designs: +) Hysteresis Motor Hysteresis motors are single phase motors in which the rotor is made up of ferromagnetic material The rotors are cylindrical in shape and have high hysteresis loss property They are generally made up of chrome, cobalt steel or alnico The stator is fed by single phase AC supply The stator has two windings: main windings and auxiliary windings The combination of the two produces a revolving magnetic field from a single phase supply They are self-starting and not need additional windings When single phase AC supply is given, a rotating magnetic field is produced This rotating magnetic field induces eddy currents in the rotor The rotor starts to move initially with a slip When the rotor reaches synchronous speed, the stator pulls the rotor into synchronism So initially the motor starts as an induction motor and later runs as a synchronous motor +) Reluctance Motor The reluctance motor is based on the principle that an unrestrained piece of iron will move to complete a magnetic flux path where the reluctance is minimum The stator has the main winding and the auxiliary windings just like the hysteresis motor These help to create a rotating magnetic field The rotor of a reluctance motor is a squirrel cage rotor with some teeth removed to provide the desired number of salient Nguyễn Khánh Hùng Khôi 19810430152 Tiếng Anh Chuyên Ngành poles The reluctance becomes minimum when the rotor is aligned with the magnetic field of the stator When single phase AC supply is given, the motor starts as an induction motor The rotor tries to align itself with the magnetic field of the stator and experiences reluctance torque But due to inertia, it exceeds the position and again tries to align itself during the next revolution In this manner, it starts to rotate Once it reaches 75% of synchronous speed, the auxiliary windings are cut off When the speed reaches synchronous speed, the reluctance torque pulls it into synchronism The motor remains in synchronism due to synchronous reluctance torque +) Permanent Magnet Synchronous Motors The rotor is made up of permanent magnets They create a constant magnetic flux The rotor locks in synchronism when the speed is near synchronous speed They are not self-starting and need electronically controlled variable frequency stator drive Direct Current Excited Motor Direct current excited synchronous motors need a DC supply to the rotor to generate rotor magnetic field A direct current excited motor has both stator windings as well as rotor windings They can either have cylindrical rotors or salient pole rotors They are not self-starting and need damper windings to start Initially, they start as an induction motor and later attains synchronous speed Nguyễn Khánh Hùng Khôi 19810430152 Tiếng Anh Chuyên Ngành 2.3 Structure The construction of synchronous motor is similar to that of a synchronous alternator Most of the synchronous motors construction uses the stationary armature and rotating field winding This type of construction as an advantage than DC motor type where the armature used is of rotating type Nguyễn Khánh Hùng Khôi 19810430152 Tiếng Anh Chuyên Ngành 2.4 Working principle The principle of operation of a synchronous motor can be understood by considering the stator windings to be connected to a three-phase alternating-current supply The effect of the stator current is to establish a magnetic field rotating at 120 f/p revolutions per minute for a frequency of f hertz and for p poles A direct current in a p-pole field winding on the rotor will also produce a magnetic field rotating at rotor speed If the rotor speed is made equal to that of the stator field and there is no load torque, these two magnetic fields will tend to align with each other As mechanical load is applied, the rotor slips back a number of degrees with respect to the rotating field of the stator, developing torque and continuing to be drawn around by this rotating field The angle between the fields increases as load torque is increased The maximum available torque is achieved when the angle by which the rotor field lags the stator field is 90° Application of more load torque will stall the motor Nguyễn Khánh Hùng Khôi 19810430152 10 Tiếng Anh Chuyên Ngành One advantage of the synchronous motor is that the magnetic field of the machine can be produced by the direct current in the field winding, so that the stator windings need to provide only a power component of current in phase with the applied stator voltage—i.e., the motor can operate at unity power factor This condition minimizes the losses and heating in the stator windings The power factor of the stator electrical input can be directly controlled by adjustment of the field current If the field current is increased beyond the value required to provide the magnetic field, the stator current changes to include a component to compensate for this overmagnetization The result will be a total stator current that leads the stator voltage in phase, thus providing to the power system reactive volt-amperes needed to magnetize other apparatuses connected to the system such as transformers and induction motors Operation of a large synchronous motor at such a leading power factor may be an effective way of improving the overall power factor of the electrical loads in a manufacturing plant to avoid additional electric supply rates that may otherwise be charged for low power-factor loads 2.5 Speed control methods for the synchronous AC motors Synchronous motors are constant speed motors They run at the synchronous speed of the supply They are generally used for constant speed operation under no load conditions such as to improve the power factor Synchronous motors have fewer losses than induction motors at a given rating The speed of a synchronous motor is given by N= 120 f p As you can see, the synchronous speed depends on the frequency of the supply and the number of poles of the rotor Changing the number of poles is not easy, so we Nguyễn Khánh Hùng Khôi 19810430152 11 Tiếng Anh Chuyên Ngành not use that method However, with the invention of solid-state devices, the frequency of the current fed to the synchronous motor can be varied We can control the speed of the synchronous motor by changing the frequency of the supply to the motor We can use a combination of rectifiers and inverters to control the speed of synchronous motors They can be used in two ways:  Inverter Fed Open Loop Synchronous Motor Drive: In this method, the synchronous motor is supplied by variable frequency inverter in an open loop By open loop, we mean that there is no feedback given to the supply The inverter has no information about the current position of the rotor This method is preferable when highly accurate speed control is not required Supply from the mains is fed into the rectifier inverter set where desired frequency can be attained Depending on the frequency, the synchronous speed of the motor can be varied  Self Synchronous (Closed – Loop) Operation: We use self-synchronous (closed-loop) operation when highly accurate speed control is required In this method, the inverter output frequency is determined by the speed of the rotor The speed of the rotor is fed back to the differentiator The difference between the preset speed and the actual speed is fed to the rectifier Accordingly, the inverter changes the frequency and adjusts the speed of the motor We get more accurate control over the motor speed with the closed loop operation For example, if speed gets reduced (due to increase in load), the stator supply frequency gets reduced so that the rotor stays in synchronism with the stator magnetic field No spontaneous oscillation or hunting occurs in this method 2.6 Applications Synchronous motors can be used toraise overall the power factor of the installation When a synchronous motor is run without load with over-excitation for improving the power factor of an installation, it is called as the synchronous capacitor or synchronous condenser Synchronous motors are also used to regulate the voltage at the end of transmission lines Because of the higher efficiency possible with synchronous motors, they can be used for loads where constant speed is required Synchronous motors can be built for speeds as low as 120 RPM They are wellsuited for direct connection to reciprocating compressors Nguyễn Khánh Hùng Khôi 19810430152 12 Tiếng Anh Chuyên Ngành Chương 3: Introduction to PLC Mitsubishi 3.1 What is PLC? 3.1.1 Definition Programmable Logic Controller, PLC, or Programmable Controller is a digital computer used for automation of industrial processes, such as control of machinery on factory assembly lines Unlike general-purpose computers, the PLC is designed for multiple inputs and outputs arrangements, extended temperature ranges, immunity to electrical noise, and resistance to vibration and impact Programs to control machine operation are typically stored in battery-backed or non-volatile memory A PLC is an example of a real time system since output results must be produced in response to input conditions within a bounded time, otherwise unintended operation will result 3.1.2 Features The PLC engineering environment has undergone outstanding innovation and growth.We are now entering the era of MELSEC Engineering Software! MELSEC's many different software products provide solutions for TCO reduction in an engineering environment, using methods such as improving design efficiency, shortening debugging time, reducing downtime, and data holding  iQ Works: This integrated software suite includes various programming software for PLC, motion control, and GOT  GX Works3: The next-generation engineering software contributes to development cost reduction with its intuitive programming environments  GX Works2: This sequence programming software uses the program assets cultivated by GX Developer to pursue a more comfortable level of operability  PX Developer: This software enables easy loop control programming with simple drag & drop operations  MX Component: This Active X controller library enables easy communication processing from the PC and tablet to PLC, without the need for communication protocol awareness  MX Sheet: Software which uses Excel to easily monitor, log, collect alarm information and change configurations for the PLC  iQ AppPortal: MELSOFT iQ AppPortal is software used to manage assets integrated for each purpose, such as project files of MELSOFT products or design drawings/documents  FieldDeviceConfigurator: A Field Device managing/setting software which is MITSUBISHI ELECTRIC products and it is corresponding to FDT/DTM open specification And it can be used as a FDT frame application to set the parameters of Field Device, or to maintain/adjust the device Nguyễn Khánh Hùng Khôi 19810430152 13 Tiếng Anh Chuyên Ngành  Other engineering softwares: Lineup of various software to support the MELSEC Series engineering environment  Peripheral equipment support tools: Lineup of various free tools that further simplify development of the MELSEC Series  e-Manual: e-Manual for the Mitsubishi FA product users for quick search of necessary information 3.1.3 Applications Automotive: Improve productivity and realize flexibility in different automotive assembly lines with high-accuracy motion control, including linear/circular interpolation and electric cam profile Automated warehouse: Realize advanced logistics coordination and eliminate errors in repetitive processes Servo-based high-speed material handling and highly accurate positioning improving productivity and reduce energy consumption Food and beverage, CPG: Realize improvements in various packaging applications such as high-speed filling, which requires a highly accurate, continuous feed rate and precision Semiconductor: Reduce maintenance costs using the high-durability MELSEC Series Having the compact, robust design desired for semiconductor manufacturing, MELSEC products solve the small footprint, high-performance requirements Nguyễn Khánh Hùng Khôi 19810430152 14 Tiếng Anh Chuyên Ngành Pick-and-place: Achieve highly precise, fast and accurate placement of components in various sizes and shapes such as that required by SMT pick-and-place equipment, further improving productivity Flat panel display (FPD): Improve the large data bandwidth and high-performance requirements common in FPD manufacturing processes using MELSEC's integrated control platform The integrated controller and network solution offer increased flexibility and enhanced performance Renewable energy Easily integrate renewable energy plant management utilizing plant-wide data acquisition and extensive real-time control, thereby reducing overall investment and maintenance costs 3.1.4 What is timing diagram Timer accumulative timers of four types: low-speed timer, high-speed timer, lowspeed integrator, and high-speed integrator The PLC takes a certain amount of time to react to changes The total response time of the PLC is a fact that has to be considered while selecting a PLC for some application where speed is a concern Hence, Input Response Time + Program Execution Time + Output Response Time = Total Response Time Having understood the concept behind the response Nguyễn Khánh Hùng Khôi 19810430152 15 Tiếng Anh Chuyên Ngành time, let us see what happens in a typical PLC Applications The PLC can only see an input turn ON/OFF when its looking In other words, it only looks at its inputs during the check input status part of the scan 3.1.5 Advantages and disadvantages of PLCs Advantages:  Small physical size & shorter project time  Cost effective for controlling complex system  Reliability  Less and simple wiring  Faster response  Remote control capability  More flexibility  Ease of maintenance / troubleshooting Disadvantages:  Fixed circuit operation  PLCs manufacturers offer only closed loop architecture  PLCs are propitiatory, which means software and parts one manufacturer can’t be easily used in combination with part of another manufacturer  Number of optional modules must be added to maximize flexibility and performance 3.2 What are differences between PLC and traditional relay circuits? Speed of response IO capacity Logic development Redundancy Architecture PROGRAMMABLE LOGIC CONTROLLERS (PLC) PLCs are can respond to a change within one-tenth of a second A PLC is capable of handling few hundred IOs When it comes to analog IOs, it can handle tens of them PLC can programmed be programmed based on our application PLCs can be made redundant with additional hardwares which makes them expensive than DCS PLCs have a simple and flexible architecture A PLC system consists of controllers, IO modules, HMIs and an Nguyễn Khánh Hùng Khôi 19810430152 DISTRIBUTED CONTROL SYSTEMS (DCS) DCS are slower than PLCs Typical respond time of DCS is 30ms A DCS can handle thousands of IOs It can handle hundreds or even thousands of analogs IOs and PID functions DCS comes with built-in control functions that need to be configured based on the application Redundancy is a default feature of distributed control systems DCS systems are less flexible They come with controllers, IO systems, database servers, engineering and operating 16 Tiếng Anh Chuyên Ngành Application Cost engineering software PLCs are best suited for dedicated applications that changes less often Less expensive servers DCS is suitable for complex processes that require advanced process control capability More expensive 3.3 Select and present briefly a PLC of Mitsubishi FX1S Base Units MITSUBISHI PLC FX1S series base units are available with 10 to 30 input/output points It is possible to choose between relay and transistor output type Special Features of MITSUBISHI PLC FX1S series  Integrated power supply (AC or DC powered)  Maintenance-free EEPROM memory  Ample memory capacity (2000 steps) and device ranges  High-speed operations  Incorporated positioning control  Integrated real-time clock  System upgrades by exchangeable interface and I/O adapter  boards for direct fitting into the base unit  LEDs for indicating the input and output status  Standard programming unit interface  User-friendly programming systems, including IEC 61131.3  (EN 61131.3)-compatible programming software, HMIs and  hand-held programming units Applications Customer Confidence The FX Family is the PLC of choice across the world’s industries and applications At Mitsubishi Electric we pride ourselves on our close working relationship with our customers By listening to customer needs Mitsubishi Electric has learnt to understand the requirements of modern applications and have developed PLC solutions that offer quality, reliability and a product that customers want The success of this approach has been reflected in the sales figures of our products – now surpassing the million milestone International Recognition and Reliability Mitsubishi has a reputation for producing high quality products This comes, in part from our commitment to understanding and meeting the requirements of international standards and directives In today’s world of manufacturing, customers require durable products that can cope with the day in day out tasks of the application they control To ensure our high-levels of product reliability, Mitsubishi Electric’s quality control program leaves nothing to chance, resulting in high-level of quality that customers can rely on Nguyễn Khánh Hùng Khôi 19810430152 17 ... briefly a PLC of Mitsubishi Nguyễn Khánh Hùng Khôi 19810430152 Tiếng Anh Chuyên Ngành LỜI CẢM ƠN Trong thời gian làm báo cáo chuyên đề, em nhận nhiều giúp đỡ, đóng góp ý kiến bảo nhiệt tình thầy... em có sở lý thuyêt tạo điều kiện gúp đỡ em trình làm báo cáo chuyên đề Tuy vậy, với kinh nghiệm kiến thức cịn thiếu sót nên báo cáo chuyên đề em chưa hoàn thiện lắm, em mong sử dẫn chân thành... bè tạo kiện, quan tâm, giúp đỡ em suốt q trình học tập hồn thành báo cáo Nguyễn Khánh Hùng Khôi 19810430152 Tiếng Anh Chuyên Ngành Chương 1: Introduction to power sources (DC and AC power) 1.1

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