Constant torque for motors connected in parallel or special motors

ELECTRICAL-INSTALLATION-CALCULATIONS-ADVANCED-FOR-TECHNICAL-CERTIFICATE-AND-NVQ-LEVEL-3-EIGHTH-EDITION-PDF

The leakage path must have a low enough impedance (Z2) to allow adequate earth leakage current to flow to “blow' the circuit fuse or Operate the circuit breaker and isolate the faulty circuit within a Specified time, usually either 5s or 0.4s. BS 7671 gives guidance to the permissible earth-loop Impedance values to meet the disconnection times and that document and the IET On-Sife Guide contain tables which list types of protectve device and specify the maximum measured earth fault loop impedance ¡In ohms for each rating of the specific device. Where precise disconnection times are demanded then BS 7671 Appendix 3 contains characteristic curves for fuses and circuit breakers.

206

Recent Developments of Electrical Drives - Part 29 pdf

The field-and-circuit model [1,5] is made by the assumption of a 2D electromagnetic field. In this model, coil outhangs and shorting rings of the rotor were taken into account by joining properly lumped parameters to several circuits. The application of the described method to model the magnetic field distribution in an induction motor, taking into account the movement of the rotor, required the introduction of a special element to the model which properly joined the unmoving and moving parts.

10

MITSUBISHI MOTORS DOCX

Interpublic Group of Cos. – David Bell, chairman and Chief Executive Officer Headquarters: New York, NY Interpublic bought New York-based Deutsch Inc. last November for $265 million in stock. Deutsch Inc. is a full-service integrated marketing and communications company. Deutsch works with blue-chip clients including Mitsubishi Motors North America, DIRECTV, Coors, Revlon, Snapple, Novartis, Bank of America, MCI and Tommy Hilfiger. Deutsch offers clients an array of services including advertising, direct marketing (directDeutsch), Interactive (iDeutsch), design (designDeutsch) and public relations, promotions, and events (Deutsch PR Promo Plus). Deutsch has offices in New York, Los Angeles, Chicago, Miami and Toronto.

25

MOLECULAR MOTORS POT

Primitive Motile Systems in Cell Biology , the field has moved from the phenomeno- logical to the mechanistic and from the largely structural to the primarily molecu- lar. We have come to appreciate that at every level of complexity the cell operates through molecular machines. Some of these machines are single molecules that carry out one specific task, undergoing only small structural changes in the pro- cess. Others are macromolecular complexes composed of dozens, even hundreds of different components engaged in elaborate biochemical operations. Among the multitude of molecular machines of a cell, one group stands out owing to its ability to generate one of the hallmark characteristics of living systems: move- ment. The chapters of this book offer insights into the workings, interactions and functions of these remarkable molecules which are responsible for various forms of movement encountered in cells. The subdivision of the book into five sections developed naturally. First we learn about the basic designs of some of the most pro- minent cellular motors before considering their mechanochemistry; the role of mo- tors in the context of elaborate cellular activities is considered next, followed by ex- amples of defects which result when motors run ‘wild’; finally, biomotors are put into perspective with regard to nanobiotechnological applications and other types of molecular motors. The outcome is a pretty sizeable book, as can plainly be seen. Nevertheless, it is but an introduction to the subject, as other types of biolo- gical machines exist that could also, with some justification, be called motors but are not considered here for reasons of space. It is my hope, however, that salient features of cellular motors are covered even though gaps undoubtedly remain.

582

AC motors fundamental

Sự khác biệt giữa động cơ DC&AC Trong động cơ DC, dòng DC chạy trong cuộn dây của rotor, cuộn dây này đặt trong từ trường. Từ trường sẽ tương tác với khung dây để tạo ra chuyển động. Trong động cơ AC, dòng AC không chạy trong rotor mà chạy trong các cuộn dây stator để sinh từ trường Mặt cắt ngang của động cơ AC Giải thích hoạt động của động cơ AC sơ cấp Dùng trong máy giặt, bơm nước, máy hút bụi v…v Tạo ra sự lệch pha giữa cuộn khởi động từ và cuộn chính (giai đoạn đầu, chạy như 2 pha, 2 cặp cực) Sau khi chạy đến 70% tốc độ định mức, khóa ngắn mạch cuộn tạo lệch pha chạy với cuộn chính (chạy 1 pha, 1 cặp cực)

24

ROTOFLUID COUPLING P1 PPSX

95.4P-AB 1740 1300 I Giunti tra parentesi, si devono impiegare per potenza nominale interamente assorbita in continuo e/o per lavori gravosi The coupling sizes in brackets must be selected for nominal power totally required in continuos or /and for heavy duty Gli elementi in gomma “R” sono disponibili in gomma telata con Fattore di Servizio doppio. Rubber elements “R” are also available in reinforced fabrik version with double Service Factor.

30

THE INDUCTION MACHINE HANDBOOK CHUONG 4

4.12. THE MMF OF ROTOR WINDINGS Induction machine rotors have either three-phase windings star-connected to three-phase slip rings or have squirrel cage type windings. The rotor three- phase windings are made of full pitch coils and one or two-layers located in semiclosed or semiopen slots. Their end connections are braced against centrifugal forces. Wound rotors are typical for induction machines in the hundreds and thousands of kW ratings and more recently in a few hundreds of MW as motor/generators in pumped storage hydro power plants.

43

Altivar 71Variable speed drives for synchronous motors and asynchronous motors Installation pptx

Above 2.5 kHz, the drive will reduce the switching frequency automatically in the event of excessive temperature rise. For continuous operation above 2.5 kHz, derating must be applied to the nominal drive current in accordance with the curves on pages 22 and 23 . (2) Typical value for the indicated motor power, with a standard 4-pole motor on a line supply with the indicated "Max. prospective line Isc". (3) The drives are supplied as standard with a DC choke, which must be used when connecting a drive to the three-phase supply.

78

Schneider Electric-Altivar 71 Variable speed drives for synchronous motors and asynchronous motors potx

Note: • If using an additional input filter, it should be installed under the drive and connected directly to the line supply via an unshielded cable. Link 10 on the drive is then established via the filter output cable. • The HF equipotential ground connection between the drive, motor and cable shielding does not remove the need to connect the PE protective conductors (green-yellow) to the appropriate terminals on each unit.

49

MECHANICAL SYSTEMS DESIGN HANDBOOK P21 PPS

The main drawback of the classical structure comes from commutation. Graphite brushes and a copper bar commutator introduce friction, sparking, and the wear of commutating parts. Sparking is one of the factors that limits motor driving capability. It limits the current at high rotation speed and thus high torques are only possible at low speed. These disadvantages can be avoided if wire windings are placed on the stator and permanent magnets on the rotor. Electronic commutation replaces the brushes and copper bar commutator and supplies the commutated voltage (rectangular or trapezoidal shape of signal). Such motors are called brushless DC motors. Sometimes, the term synchronous AC motor is used although a difference exists (as will be explained later). In addition to avoiding commutation problems, increased reliability and improved thermal capacity are achieved. On the other hand, brushless motors require more complex and expensive control systems. Sensors and switching circuitry are needed for electronic commutation.

34

MODELING MEASUREMENT AND CONTROL P21

The main drawback of the classical structure comes from commutation. Graphite brushes and a copper bar commutator introduce friction, sparking, and the wear of commutating parts. Sparking is one of the factors that limits motor driving capability. It limits the current at high rotation speed and thus high torques are only possible at low speed. These disadvantages can be avoided if wire windings are placed on the stator and permanent magnets on the rotor. Electronic commutation replaces the brushes and copper bar commutator and supplies the commutated voltage (rectangular or trapezoidal shape of signal). Such motors are called brushless DC motors. Sometimes, the term synchronous AC motor is used although a difference exists (as will be explained later). In addition to avoiding commutation problems, increased reliability and improved thermal capacity are achieved. On the other hand, brushless motors require more complex and expensive control systems. Sensors and switching circuitry are needed for electronic commutation.

34

GALE ENCYCLOPEDIA OF AMERICAN LAW 3RD EDITION VOLUME 4 P8 POT

create a lender of LAST RESORT for U.S. financial institutions. The Great Depression of the 1930s led many homeowners to default on their mortgages. By 1933, banks were foreclosing on nearly one thousand homes per day. President FRANKLIN D . ROOSEVELT and Congress responded by creating the Home Owners ’ Loan Corporation, which purchased defaulted mortgages from the banks and then refinanced the mortgages at lower, fixed rates. The agency issued mortgages to about one million homeowners. By the time the agency dissolved in 1951, more than 80 percent of the borrowers had repaid their mortgages on time or early. Lee Davison, a historian with the FEDERAL DEPOSIT INSURANCE CORPORATION , noted that the program earned the government a small profit. “ You save 80 percent of the people from being tossed out of their homes, and it didn ’ t end up costing the government a dollar, ” he said.

10

THIẾT KẾ MÔ HÌNH XE CHẠY BẰNG NĂNG LƯỢNG MẶT TRỜI

TRAVEL MOTORS Axial piston motors with brake valve and spring-set/hydraulic- released multiplate disc brake RELIEF AND BRAKE VALVES z Each hydraulic circuit incorporates large-capacity r[r]

16

XE Ô TÔ GENERAL MOTORS

Xe ô tô GENERAL MOTORS (PRACTIICE ELECTRIICAL WIIRIING DIIAGRAMS)

97

RELIABILITY AND SAFETY IN RAILWAY pot

environment in multiple levels was discussed in the paper by Erik Hollnagel and David.D. Woods. Prior to this, Barry A. Turner relying upon a similar concept of collective adoption of simplified assumptions into a framework of ‘bounded rationality’ helped deduced the fact that large scale intelligence failures are seen to occur in the organisational and inter- organisational practices prior to the occurrence of disaster. Drawing upon three case studies of public inquiries in United Kingdom, Turner hypothesized that a set of cultural beliefs about the world and its hazards in the social context and associated pre-cautionary norms set out in the laws, codes of practice, mores and folkways are the starting point of events in a process made up of 6 stages ending up with cultural re-adjustment. One of the public inquiry studied was the Hixon accident which is relevant in the railway context (B. A. Turner 1976). Earlier to this period, the concepts of organism, adaptive behavior and regulation in an environment were studied by Ashby (W. Ashby 1960), (W. Ashby 1960), (Ashby and Conant 1970). The concepts of representation of external reality as an object and the four roots of the principle of sufficient reason were discussed by Arthur Schopenhauer (Schopenhaeur 1820/2006). These set of ideas were followed by Leo Tolstoy (Tolstoy 1887/1930), and Alfred North Whitehead (Whitehead 1927/1978). Alfred North Whitehead traced the origin of these concepts back to the Buddhists whereas Arthur Schopenhauer traced the origin of these concepts back to the Upanishads. The principle Upanishads were translated from Sanskrit to English by Valerie Roebuck (Valerie 2003). Valerie Roebuck in the contemporary period traces the origin to pre-buddhistic Upanishad era in the fifth or sixth centuries BCE (Valerie 2003). Author has learnt from Jens Rasmussen and others that the concept of system coming into being can be traced back to ancient Greek times represented by Aristotelian notion of causation ( (Rasmussen, Pejtersen and Goodstein 1994). The concepts of self or soul and external reality are mentioned by Aristotle in the ancient Greek times in the book VII on Politics (Aristotle 323 BC/1951).

430

ADVANCES IN MOTOR TORQUE CONTROL PDF

force/torque control techniques found many applications in variety of disciplines such as bilateral teleoperation, microsystems and micro manipulation. Furthermore, the previous force observers can be combined with most of the relevant existing force control techniques such as the hybrid position/force control, stiffness control, the resolved acceleration based force control and the impedance control to provide an efﬁcient tool which can be used in most of the industrial force control applications. The sensorless force control techniques are not only useful in the sense of avoiding force sensors but also in reducing the complicity of the entire control system and increasing their stability. In addition, this work present a novel sensorless force servoing techniques based on the action reaction state observer (Khalil & Sabanovic, 2011) which allows realizing the sensorless force control without taking any measurement from the robot or the environment except a single measurement form the robot actuator. The conventional force observer requires having velocity measurement of the end-effector in contact with the environment and using it as basis for the estimation process. The action reaction state observer allows realizing the interaction force observer without measuring position or velocity of the non-collocated end-effector in contact with the environment (Khalil & Sabanovic, n.d.), therefore allowing the force control to be realized with minimum amount of measurements from the dynamical system.

122

DYNAMIC ENGLISH BOOK THREE PART 29 PPT

Larry: Alri i i ght. Ready for Functioning in Business. Cue Music... Vietnamese Explanation Trong phần Anh Ngữ Thương Mại Trung Cấp, Elizabeth giới thiệu cho ta phần “A New Customer, Part 1, Thân chủ mới, Phần 1.” Ta cũng nghe những câu dùng khi chào đón. This program focuses on Greetings. Ta nghe phần phỏng vấn ông Stewart Chapman, phó Chủ tịch Phụ trách Ðiều hành của hãng chế tạo xe hơi Federal Motors. Trucks.=xe vận tải. Passenger cars=xe du lịch.

7

thiết kế bộ điều khiển vận tốc và vị trí 3 động cơ AC

1. AC 3 PHASE MOTOR I. INTRODUCTION  The three-phase induction motors are the most widely used electric motors in industry.  Almost 80% of the mechanical power used by industries is provided by three phase induction motors because of its simple and rugged construction, low cost, good operating

36

Robot Mechanisms and Mechanical Devices Illustrated P1

xiv Introduction outdoor and indoor environments, some of which can be any size (like rocks), others that cannot (like stair cases). I intentionally left out the whole world of hydraulics. While hydraulic power can be the answer when very compact actuators or high power density motors are required, it is potentially more danger- ous, and definitely messier, to work with than electrically powered devices. It is also much less efficient—a real problem for battery pow- ered robots. There are many texts on hydraulic power and its uses. If hydraulics is being considered in a design, the reader is referred to Industrial Fluid Power (4 volumes) 3rd ed., published by Womack Education Publications.

30

MOTORS ANH MOTORS CONTROL

[r]

29

AC MACHINES EBOOK

If the rotor is consist of windings, TRANG 9 ELECTRIC MOTORS TRANG 10 TRANG 11 ELECTRIC MOTORS Electric Motors Alternate Current Motors ACM Direct Current Motors DCM Synchronous Inductio[r]

43

CHIẾN lược KINH DOANH của GENERAL MOTORS

CHIẾN lược KINH DOANH của GENERAL MOTORS CHIẾN lược KINH DOANH của GENERAL MOTORS CHIẾN lược KINH DOANH của GENERAL MOTORS CHIẾN lược KINH DOANH của GENERAL MOTORS CHIẾN lược KINH DOANH của GENERAL MOTORS CHIẾN lược KINH DOANH của GENERAL MOTORS CHIẾN lược KINH DOANH của GENERAL MOTORS CHIẾN lược KINH DOANH của GENERAL MOTORS CHIẾN lược KINH DOANH của GENERAL MOTORS CHIẾN lược KINH DOANH của GENERAL MOTORS CHIẾN lược KINH DOANH của GENERAL MOTORS CHIẾN lược KINH DOANH của GENERAL MOTORS CHIẾN lược KINH DOANH của GENERAL MOTORS CHIẾN lược KINH DOANH của GENERAL MOTORS CHIẾN lược KINH DOANH của GENERAL MOTORS CHIẾN lược KINH DOANH của GENERAL MOTORS CHIẾN lược KINH DOANH của GENERAL MOTORS CHIẾN lược KINH DOANH của GENERAL MOTORS CHIẾN lược KINH DOANH của GENERAL MOTORS CHIẾN lược KINH DOANH của GENERAL MOTORS CHIẾN lược KINH DOANH của GENERAL MOTORS CHIẾN lược KINH DOANH của GENERAL MOTORS CHIẾN lược KINH DOANH của GENERAL MOTORS CHIẾN lược KINH DOANH của GENERAL MOTORS CHIẾN lược KINH DOANH của GENERAL MOTORS CHIẾN lược KINH DOANH của GENERAL MOTORS CHIẾN lược KINH DOANH của GENERAL MOTORS CHIẾN lược KINH DOANH của GENERAL MOTORS CHIẾN lược KINH DOANH của GENERAL MOTORS CHIẾN lược KINH DOANH của GENERAL MOTORS CHIẾN lược KINH DOANH của GENERAL MOTORS CHIẾN lược KINH DOANH của GENERAL MOTORS CHIẾN lược KINH DOANH của GENERAL MOTORS CHIẾN lược KINH DOANH của GENERAL MOTORS CHIẾN lược KINH DOANH của GENERAL MOTORS CHIẾN lược KINH DOANH của GENERAL MOTORS CHIẾN lược KINH DOANH của GENERAL MOTORS CHIẾN lược KINH DOANH của GENERAL MOTORS CHIẾN lược KINH DOANH của GENERAL MOTORS CHIẾN lược KINH DOANH của GENERAL MOTORS CHIẾN lược KINH DOANH của GENERAL MOTORS CHIẾN lược KINH DOANH của GENERAL MOTORS CHIẾN lược KINH DOANH của GENERAL MOTORS CHIẾN lược KINH DOANH của GENERAL MOTORS CHIẾN lược KINH DOANH của GENERAL MOTORS

16

MCGRAW HILL THE ROBOT BUILDER''''S BONANZA PART 8 DOCX

of the motor. Note as well that the running and stall torque of the motor will be greatly increased. Make sure that the torque specification on the motor is for the output of the gearbox, not the motor itself. With most gear reduction systems, the output shaft is opposite the input shaft (but usu- ally off center). With other boxes, the output and input are on the same side of the box. When the shafts are at 90 degrees from one another, the reduction box is said to be a “right- angle drive.” If you have the option of choosing, select the kind of gear reduction that best suits the design of your robot. I have found that the “shafts on opposite sides” is the all- around best choice. Right-angle drives also come in handy, but they usually carry high price tags.

35

MOTORS FOR MAKERS A GUIDE TO STEPPERS SERVOS AND OTHER ELECTRICAL MACHINES PDF

P p parallel, 52 parameters, dead bandwidth parameter, 75 patents, Tesla Motors, 272 dual-motor drive and control system, 275-277 flux controlled motor management, 272-273 induction moto[r]

317

MOMENT OF INERTIA AND TORQUE PERFORMANCE SENSORLESS MEASUREMENT FOR HDD USED SPINDLE MOTORS

TRANG 8 NOMENCLATURE V NOMENCLATURE ADB: AERO-DYNAMIC-BEARING ADC: ANALOG DIGITAL CONVERTER AIO: ALL-IN-ONE SPINDLE MOTOR TESTING SYSTEM AMB: ACTIVE-MAGNETIC-BEARING BACK-EMF: BACK ELECT[r]

125

Foreign Exchange Hedging Strategies at General Motors: Transactional and Translational Exposures Competitive Exposure

Foreign Exchange Hedging Strategies at General Motors: Transactional and Translational Exposures Competitive Exposure about General Motors GM and its Foreign Exchange Policy, GM’s Competitive Exposure,...

5

Thông tin cơ chế - Thiết bị cơ khí P10 pot

The constant displacement hydraulic motor and the variable displacement hydraulic motor are connected in series with the variable delivery pump. Thus, the relative speeds of the two hydraulic motors will always remain substantially the same. The displacement of the vari- able speed motor is then adjusted to an amount slightly greater than the displace- ment of the constant-speed motor. This tends to give the winding roll a speed slightly greater than the feed roll speed. This determines the tension, because the winding roll cannot go faster than the feed roll. Both are in contact with the paper roll being wound. The pressure in the hydraulic line between the constant and variable displacement pumps will increase in proportion to the winding ten- sion. For any setting of the winding

29

XE Ô TÔ GENERAL MOTORS

Tài liệu về Xe ô tô GENERAL MOTORS.

97

ĐỘ NHẠY CẢM CẠNH TRANH TẠI GENERAL MOTORS

66

Anh ngữ sinh động bài 126 pptx

Vietnamese Explanation Trong phần tới, ta nghe Larry kể cuối tuần vừa qua, anh ta là người hướng dẫn cho gia đình người anh đi thăm thành phố Washington. Tour guide=hưóng viên du lịch. To show people around.=hướng dẫn mọi người đi thăm cảnh. Tiring=mệt. [Phân biệt tiring và tired. Guiding relatives around town was a tiring job for Larry=hướng dẫn họ hàng quanh thành phố là một việc gây mệt nhọc đối với Larry. He was tired after walking all day.=anh ta mệt sau một ngày đi bộ.] Close relatives=họ hàng gần. The Air and Space Museum.=Bảo tàng viện Hàng không và Không gian. Zoo=sở thú. The Capitol=điện Capitol, tức là Quốc hội Hoa Kỳ. Washington Monument=đài kỷ niệm tổng thống Washington, trông như cái tháp bút chì khổng lồ.

7

INSPECTION OF VERTICAL TRANSPORTATION EQUIPMENT_4 PPTX

Dumbwaiter performance is directly related to good electrical continuity through the commutator or slip rings. Check the slots of the commutator for any accumulation of carbon, copper dust, oil, or other substances. Check exposed armature and field terminal connections to see that they are tight. Special attention should be given to the shunt field connections of DC motors. Loose connections here could result in a runaway condition. connections not properly made may result in poor electrical conduction and points of resistance. This condition creates heat. Examine the leads to be sure they are not broken or their insulation is not cracked or broken. Improper adjustments can force motor winding to carry more current, which produces heat, which will cause insulation to deteriorate. Check to see that the motor windings are free of oil, dust, or lint deposits. Accumulations restrict cooling air circulation causing heat build-ups, which result in poor performance, insulation damage, and possibly fire.

27

control speed of DC motor using thysistor and transitor

DC motor are widely industry because of its low cost, less complex control structure and wide range of speed and torque. There are many methods of speed control of DC drives namely field control methods. DC motors provide high starting torque which is required for traction applications. In DC motor control over a large speed range, both below and above the rated speed can be achieved quite easily. DC motors have inherent disadvantage that it needs regular maintenance and it is bulky in size. DC motors are tailor made, so it is difficult to replace them. In general, armature voltage control method is widely used to control the DC drives. In this method, a controlled rectifier, is used but due involvement of power electronics elements, nonlinear torque speed characteristics are observed which are undesirable for control performance . Nowadays state of art speed control techniques of DC motor are available. Thyristor based DC drives with analog and digital feedback control schemes are used. Phase locked loop control technique is also used for precise speed control and zero speed regulation. In past, many researchers presented various new converter topologies of DC motor control for different applications of industry 5,6,8,9, but at the basic level in all of them thyristor based ACDC converter are used.

19

Chapter 2: Construction and steady-state operation of induction motors

Construction and operating principles of induction motors are presented in this chapter. The generation of a revolving magnetic field in the stator and torque production in the rotor are described. The per-phase equivalent circuit is introduced for determination of steady-state characteristics of the motor. Operation of the induction machine as a generator is explained.

27

The impact of demagnetization on the feasibility of permanent magnet synchronous motors in industry applications

Permanent magnet (PM) motors are rapidly replacing the dominant induction motors in industrial applications including pumps, fans, and compressors. PM motors are also gaining ground in critical sustainable energy applications such as wind systems, photovoltaic pumping systems and electric vehicles. Compared to induction motors, PM have higher efficiency. In this paper, the financial feasibility of replacing induction motors by PM motors at various operating conditions was analyzed on a preliminary basis. The impact of partial demagnetization and full loss of excitation on the feasibility of the replacement was also preliminarily investigated. It is found that the feasibility of replacement was less sensitive to reduction in the life time of PM motors than reduction in efficiency due to partial demagnetization. While detailed and lengthy studies are planned in the future, investigation outcomes suggest that the replacement remains feasible despite risks of demagnetization when utilization rates are above 50%. Details of the investigation are reported in the paper.

6