Object Detection on Monorail Track with Superconducting Magnet and Liner Motor

Transcription

1 International Journal of Technical Innovation in Modern Engineering & Science (IJTIMES) Impact Factor: 5.22 (SJIF-2017), e-issn: Volume 4, Issue 7, July-2018 Object Detection on Monorail Track with Superconducting Magnet and Liner Motor Ashwini R. Zade 1, Nihal D. Meshram 2, Prof. Mukund R. Salodkar 3, Amit Kumar R. Zade 4, Shamal M. Kalambe Department of Electrical Engineering, G. H. Raisoni College of Engineering & Management Amravati, Maharashtra, India 4 Department of Electrical & Power Engineering, Ballarpur Institute of Technology, Bamni, Ballarpur, Maharashtra, India 5 Department of Electrical Engineering, Rajiv Gandhi College of Engineering Research & Technology Chandrapur, Maharashtra, India Abstract: Maglev systems are becoming a popular application around the globe. Maglev trains are popular in transportation stations in big countries like Germany, China, Japan and the United States of America due to the demand for high-speed transportation, as the general public transportation services become more congested with increase of population. Maglev trains are magnetically levitated trains that traverse in a very high speed, with only electricity being its main source of energy. The train propels forward without any friction from moving mechanical parts. It has many advantages with minor drawbacks. The basis of maglev trains mechanisms are magnetic levitation. This is achieved with the principal of repulsion and attraction between two magnetic poles. There are currently three known maglev suspension systems. In this project report, we will be covering the basic principles of Electrodynamic Suspension Systems (EDS), Electromagnetic Suspension Systems (EMS) and Inductrack. The three suspension systems each have different characteristics and special features. While EDS and EMS both use only the interaction of magnets and superconductors, Inductrack uses coils on the track underneath the train body. All three suspension systems work under the same principal of magnetic levitation. The maglev propulsion systems use the interaction of stators, superconductors and magnets between the railway and the train. It has controls for speed and direction, which are based on electricity also in the case of Maglev Train if there I any obstacle occurs then with the help of IC-555 timer it can be detected. This IC is only the base but it uses another IC that is Infrared obstacle Detection kit using IC-555 Timer. Keywords Magnetic Levitation System, Electromagnetic Suspension (EMS), Electrodynamics Suspension (EDS), Inductrack, Propulsion System, Lateral Guidance Systems, Operational Control System I. INTRODUCTION Transport alongside correspondence, shapes the center of everyday existence of present day world. Ordinary rail transport through across the board is currently being viewed as wasteful as far as fuel utilization and is tedious. An authentic swap for railroads which isn't just fuel proficient yet in addition very agreeable and can achieve inconceivable speeds of around kms/hr. are Maglev Trains whose thought was given by Robert Goddard, an American Rocket researcher, in 1904 who gave a hypothesis that trains could be lifted off the tracks by the utilization of electromagnetic rails. Numerous presumptions and thoughts were realized all through the next years, yet it was not until the point when the 1970's that Japan and Germany indicated enthusiasm for it and started inquiring about and outlining. The movement of the Maglev prepare is construct simply in light of attraction and attractive fields. This attractive field is created by utilizing powerful electromagnets. By utilizing attractive fields, the Maglev prepare can be suspended over its track, or guide way, and pushed forward. Haggles parts are killed on the Maglev prepare, permitting the Maglev prepare to basically proceed onward air without grating. IJTIMES-2018@All rights reserved 1

2 Fig. 1. Essential Function of Maglev Maglev (got from attractive levitation) utilizes attractive levitation to drive vehicles with magnets instead of with wheels, axles and course. With maglev, a vehicle is suspended a short separation far from a guide way utilizing magnets to make both lift and push. Rapid maglev trains guarantee emotional enhancements for human travel if across the board selection happens. Maglev trains move more easily and to some degree more discreetly than wheeled mass travel frameworks. Their nondependence on erosion implies that speeding up and deceleration can outperform that of wheeled transports, and they are unaffected by climate. The power required for levitation is ordinarily not an extensive level of the general vitality utilization the vast majority of the power is utilized to conquer air obstruction (drag), likewise with some other rapid type of transport. Albeit customary wheeled transportation can go quick, maglev permits routine utilization of higher best speeds than regular rail, and this compose holds the speed record for rail transportation. II. LITERATURE SURVEY The goal of using magnets to achieve high speed travel with non-contact magnetically levitated vehicles is almost a century old. In the early 1900's, Bachelet in France and Goddard in the United States discuss the possibility of using magnetically levitated vehicles for high speed transport. However, they do not propose a practical way to achieve this goal. On August 14, 1934, Hermann Kemper of Germany receives a patent for the magnetic levitation of trains. Research continues after World War II. In the 1970s and 1980s, development, commissioning, testing and implementation of various Maglev Train systems continues in Germany by Thyssen Henschel. The Germans name their Maglev system "Transrapid". In 1966, in the USA, James Powell and Gordon Danby propose the first practical system for magnetically levitated transport, using superconducting magnets located on moving vehicles to induce currents in normal aluminum loops on a guideway. The moving vehicles are automatically levitated and stabilized, both vertically and laterally, as they move along the guideway. The vehicles are magnetically propelled along the guideway by a small AC current in the guideway. In 1992, the Federal Government in Germany decides to include the 300 km long superspeed Maglev system route Berlin-Hamburg in the 1992 Federal Transportation Master Plan. In June of 1998, the US congress passes the Transportation Equity Act for the 21st Century (TEA 21). The law includes a Maglev deployment program allocating public funds for preliminary activities with regard to several projects and, later on, further funds for the design, engineering and construction of a selected project. For the fiscal years , $55 million are provided for the Maglev deployment program. An additional $950 million are budgeted for the actual construction of the first project. In November of 1999, the Chinese Ministry of Science and Technology and Transrapid International sign a letter of intent to select a suitable Transrapid route in the People's Republic of China and evaluate its technical and economic feasibility. IJTIMES-2018@All rights reserved 2

3 Types of Maglev Method III. METHODOLOGY Repulsion between like poles of permanent magnets or electromagnets. Repulsion between a magnet and a metallic conductor induced by relative motion. Repulsion between a metallic conductor and an AC electromagnet. Repulsion between a magnetic field and a diamagnetic substance. Repulsion between a magnet and a superconductor. Attraction between unlike poles of permanent magnets or electromagnets. Attraction between the open core of an electromagnetic solenoid and a piece of iron or a magnet. Attraction between a permanent magnet or electromagnet and a piece of iron. Attraction between an electromagnet and a piece of iron or a magnet, with sensors and active control of the current to the electromagnet used to maintain some distance between them. Repulsion between an electromagnet and a magnet, with sensors and active control of the current to the electromagnet used to maintain some distance between them. 3.1 Magnetic Levitation System Magnetic levitation means to rise and float in air. The Maglev system is made possible by the use of electromagnets and magnetic fields. The basic principle behind Maglev is that if you put two magnets together in a certain way there will be a strong magnetic attraction and the two magnets will clamp together. This is called "attraction". If one of those magnets is flipped over then there will be a strong magnetic repulsion and the magnets will push each other apart. This is called "repulsion". Now imagine a long line of magnets alternatively placed along a track. A line of alternatively placed magnets on the bottom of the train. If these magnets are properly controlled the trains will lift of the ground by the magnetic repulsion or magnetic attraction. On the basis of this principle, Magnetic Levitation is broken into three main types of suspension or levitation, they are A) Electromagnetic Suspension (EMS) B) Electrodynamic Suspension (EDS) C) Inductrack Fig. 2 Types of Levitation Techniques IJTIMES-2018@All rights reserved 3

4 3.2 Electomagnetic Suspension System (Ems) Electromagnetic Suspension or EMS is the first of the two main types of suspension used with Maglev. This suspension uses conventional electromagnets located on structures attached to the underside of the train; these structures then wrap around a T-shaped guide rail. This guide rail is ferromagnetic, meaning it is made up of such metals as iron, nickel, and cobalt, and has very high magnetic permeability. The magnets on the train are then attracted towards this ferromagnetic guide rail when a current runs through the guide rail and the electromagnets of the train are turned on. This attraction lifts the car allowing it to levitate and move with a frictionless ride. Vehicle levitation is analyzed via on board computer control units that sample and adjust the magnetic force of a series of onboard electromagnets as they are attracted to the guide way. The small distance of about 10mm needs to be constantly monitored in order to avoid contact between the train s rails and the guiderail. This distance is also monitored by computers, which will automatically adjust the strength of the magnetic force to bring this distance back to around 10mm, if needed. This small elevation distance and the constant need for monitoring the Electromagnetic Suspension System is one of its major downfalls. Fig. 3 Ems suspension system The train also needs a way to stay centered above the guide way. To do this, guidance coils and sensors are placed on each side of the train s structures to keep it centered at all points during its ride, including turns. Again, the gap should be around 10mm, so computers are used to control the current running through the guidance magnets and keep the gap steady. In addition to guidance, these magnets also allow the train to tilt, pitch, and roll during turns. To keep all distances regulated during the ride, the magnets work together with sensors to keep the train centered. However, the guidance magnets and levitation magnets work independently. 3.3 Electrodynamic Suspension System (EDS) The second of the two main types of suspension systems in use is the Electrodynamics Suspension (EDS). EDS uses superconducting magnets (SCM) located on the bottom of the train to levitate it off of the track. By using super cooled superconducting magnets, the electrical resistance in superconductors allows current to flow better and creates a greater magnetic field. The downside to using an EDS system is that it requires the SCMs to be at very cold temperatures, usually around 5 K (-268ºC) to get the best results and the least resistance in the coils. The Japanese Maglev, which is based on an EDS system, uses a cooling system of liquid nitrogen and helium. To understand what s really going on here, let s start from the inside out. The first major difference between EDS and EMS is the type of track. Whereas with EMS the bottom of the train hooks around the edges of the track, an EDS train literally floats on air, as shown in the figure. Fig.4. EDS Suspension system IJTIMES-2018@All rights reserved 4

5 The outside guides act like the cushions used to prevent gutter balls in bowling only an EDS train has a magnetic safety net to keep the train centered, unlike your traditional bowling. If the train is knocked in the horizontal direction, the field on the side it shifts to becomes greater and the field on the opposite side weakens due to this increase in distance. Therefore, in order to restore equal magnetic forces from each side, the train is pushed back into the center of the guide way and the strength of the magnetic fields reduces to their normal strength. This is one reason why EDS is a much more stable suspension system. A second reason why the Electrodynamics Suspension system is more stable is that it is able to carry a much heavier weight load without having its levitation greatly affected. As the gap between the train and vehicle decreases, forces between the SCMs located on the train and the magnets on the track repel each other and increase as the train gets heavier. For example, if weight is added to the train, it is going to want to get closer to the track; however it cannot do so because repulsion forces grow stronger as the poles on the train sink closer to the similar poles on the guide way. The repulsive forces between the magnets and coils lift the train, on average, about 4 to 6 inches above the track, which virtually eliminates any safety issues regarding the train losing levitation and hitting its guide way. This brings us to the next thing we encounter as we move out from the center of the guide way. Levitation coils repel the SCMs underneath the train, providing the restoring forces to keep the train aligned. Propulsion coils are located next. The propulsion system of the Electrodynamics Suspension system is quite similar to Electromagnetic propulsion, but does vary slightly. To propel the train, the guide way has coils running along the top and bottom of the SCMs. Induced current within these coils creates alternating magnetic fields that attract or repel the SCMs, sending the train in the forward or reverse direction. Because the trains are moving by magnetic waves that push and pull it forward, it s virtually impossible for trains to collide since they are in essence riding the same magnetic waves. Fig. 5 New leading Japanese Car MLX No engine or other power source is required to keep the train moving except the initial speed that is required to begin levitation. Therefore wheels are required to keep the train moving until about 100 km/hr. (65 mph) where it can then begin to levitate. This railway provides no other means of support for the train since the bulk of the train is floating above the entire track. 3.4 Inductrack Magnetic levitation of high-speed trains has been a decades-long development in which many important advances have been made. Full-scale maglev systems have been demonstrated on test tracks in both Germany and Japan. Although these systems are marvels of modern engineering design and have achieved their design goals, commercially operating trains employing their design principles have yet to be put into operation. Among the reasons that the introduction of maglev systems has been slow to occur may be cost and complexity. For example, the German system employs servocontrolled electromagnets, attracted upward to a track consisting of precisely aligned iron plates. Because of the small pole-to-track gap (of order i centimeter), and because such systems are inherently unstable (a consequence of Earnshaw's theorem 1 ), for reasons of safety the control system for the electromagnets must meet very demanding standards and must be highly redundant. The Japanese system, on the other hand, employs superconducting magnets on the train cars, with attendant control and cryogenic system requirements. The Inductrack concept 2 aims at finding a simpler and less expensive approach to maglev, one possibly with a wider variety of applications than present systems. IJTIMES-2018@All rights reserved 5

6 Fig. 6. Schematic diagram of Inductrack concept To achieve its levitating forces, the Inductrack employs a special array of permanent magnets (Halbach arrays) on the train car. When the train is in motion the magnetic field from these magnets induces repelling currents in a close-packed array of shorted conducting circuits in the "track." Figure 6 is a schematic representation of the Inductrack concept, showing a Halbach array moving above, and close to, the upper conductors of a close-packed array of shorted circuits. Also shown is the equivalent circuit of this system. In the past, the use of permanent magnets in maglev systems has been rejected for various reasons. One reason was that it was felt that they would not produce an adequate levitation force compared to the weight of the magnets themselves. In the Inductrack, this objection has been answered by the combination of two factors: First, the Halbach array, as pioneered by Klaus Halbach for particle accelerator applications^ represents the optimally efficient use of permanent-magnet material for creating a periodic magnetic field near the lower surface of the array. It accomplishes this result by canceling the field above the array, while producing a nearly purely sinusoidally varying periodic magnetic field below the array. Second, this periodic magnetic field couples strongly to the close-packed array of circuits that comprise the "track" of the Inductrack. As a result of these two optimizing design factors, it is not necessary to employ superconducting magnets in order to achieve adequate levitating forces. Being an induction-activated, repelling-force, system, Earnshaw's theorem does not apply to the Inductrack so that it requires no control circuits to achieve Earnshaw-stability As long as the train is in motion (above a transition speed of a few kilometers per hour) it will be stably levitated. Failure of the drive system in the Inductrack would result in the train slowing down to low speed, then settling down on its auxiliary wheels prior to stopping. 3.5 Propulsion System Electrodynamics Propulsion is the basis of the movement in a Maglev system. The basic principle that electromagnetic propulsion follows is that opposite poles attract each other and like poles repel each other. This meaning that the north pole of a magnet will repel the north pole of a magnet while it attracts the south pole of a magnet. Likewise, the south pole of a magnet will attract the north pole and repel the south pole of a magnet. It is important to realize these three major components of this propulsion system. They are A large electrical power source Metal coils that line the entire guide way Guidance magnets used for alignment The Maglev system does not run by using a conventional engine or fossil fuels. The interaction between the electromagnets and guideway is the actual motor of the Maglev system. To understand how Maglev works without a motor, we will first introduce the basics of a traditional motor. A motor normally has two main parts, a stator and a rotor. The outer part of the motor is stationary and is called the stator. The stator contains the primary windings of the motor. The polarity in the stator is able to rapidly change from north and south. The inner part of the motor is known as the rotor, which rotates because of the outer stator. The secondary windings are located within the rotor. A current is applied to the secondary windings of the rotor from a voltage in the stator that is caused by a magnetic force in the primary windings. As a result, the rotor is able to rotate. IJTIMES-2018@All rights reserved 6

7 Now that we have an understanding of how motors work, we can describe how Maglev uses a variation on the basic ideas of a motor. Although not an actual motor, the Maglev s propulsion system uses an electric synchronous motor or a linear synchronous motor. The Maglev system works in the same general way the compact motor does, except it is linear, meaning it is stretched as far as the track goes. The stators of the Maglev system are usually in the guiderails, whereas the rotors are located within the electromagnetic system on the train. The sections of track that contain the stators are known as stator packs. This linear motor is essential to any Maglev system. The picture below gives an idea of where the stator pack and motor windings are located. Fig. 7 Parts of EMS The guideway for Maglev systems is made up of magnetized coils, for both levitation and propulsion, and the stator packs. An alternating current is then produced, from the large power source, and passes through the guideway, creating an electromagnetic field which travels down the rails. As defined by the Encarta Online dictionary, an alternating current is a current that reverses direction. The strength of this current can be made much greater than the normal strength of a magnet by increasing the number of winds in the coils. The current in the guideway must be alternating so the polarity in the magnetized coils can change. The alternating current allows a pull from the magnetic field in front of the train, and a push from the magnetic field behind the train. This push and pull motion work together allowing the train to reach maximum velocities well over 300 miles per hour. Fig. 8 Propulsion system in EDS This propulsion is unique in that the current is able to be turned on and off quickly. Therefore, at one instance there can be a positive charge running through a section of the track, and within a second it could have a neutral charge. This is the basic principle behind slowing the vehicle down and breaking it. The current through the guiderails is reversed causing the train to slow, and eventually to competely stop. Additionally, by reversing the current, the train would go in the reverse direction. This propulsion system gives the train enough power to accelerate and decelerate fairly quickly, allowing the train to easily climb steep hills. The levitation, guidance, and propulsion of the electromagnetic suspension system must work together in order for the Maglev train to move. All of the magnetic forces are computer controlled to provide a safe and hazard free ride. The propulsion system works hand in hand with the suspension system on the Maglev system. IJTIMES-2018@All rights reserved 7

8 3.6 Lateral Guidance Systems The Lateral guidance systems control the train s ability to actually stay on the track. It stabilized the movement of the train from moving left and right of the train track by using the system of electromagnets found in the undercarriage of the MagLev train. The placement of the electromagnets in conjunction with a computer control system ensures that the train does not deviate more than 10mm from the actual train tracks. The lateral guidance system used in the Japanese electrodynamics suspension system is able to use one set of four superconducting magnets to control lateral guidance from the magnetic propulsion of the null flux coils located on the guide ways of the track as shown in Fig.9. Coils are used frequently in the design of MagLev trains because the magnetic fields created are perpendicular to the electric current, thus making the magnetic fields stronger. The Japanese Lateral Guidance system also uses a semi-active suspension system. This system dampens the effect of the side to side vibrations of the train car and allows for more comfortable train rides. This stable lateral motion caused from the magnetic propulsion is a joint operation from the acceleration sensor, control device, to the actual air spring that dampens the lateral motion of the train car. Fig.9 Lateral guidance of track The lateral guidance system found in the German transrapid system (EMS) is similar to the Japanese model. In a combination of attraction and repulsion, the MagLev train is able to remain centered on the railway. Once again levitation coils are used to control lateral movement in the German MagLev suspension system. The levitation coils are connected on both sides of the guide way and have opposite poles. The opposite s poles of the guide way cause a repulsive force on one side of the train while creating an attractive force on the other side of the train. The location of the electromagnets on the Transrapid system is located in a different side of the guide ways. To obtain electromagnetic suspension, the Transrapid system uses the attractive forces between iron-core electromagnets and ferromagnetic rails. In addition to guidance, these magnets also allow the train to tilt, pitch, and roll during turns. To keep all distances regulated during the ride, the magnets work together with sensors to keep the train centered. 3.7 The Operational Control System The operation control system controls the operation and guarantees the safety of the Maglev system. It safeguards vehicle movements, the position of the switches, and all other safety and operational functions. Vehicles location on the track is accomplished using an on-board system which detects digitally encoded location flags on the guide way. A radio transmission system is used for communication between the central control center and the vehicles. Fig.10 Operation control of maglev IJTIMES-2018@All rights reserved 8

9 3.8 Power Supply Power supply consists of substations; track side feeder cables switch stations and other power supply equipment. Power supply system feeds the train with the power required for the train operation by energizing the long stator windings on the guide way. First, high voltage alternating current is taken from the 110kv public power grid, step-down to 20kv and 1.5kv using step-down transformer and then converted in to direct current via rectifier, then converted back to variable frequency ac current between 0 and 300Hz via rectifier. After step-up, the current will be fed to long stator winding on the guide way via guide way cables and switch stations, generating propulsion force between the stator and on-board magnets. The rectification equipment and motor stators etc of the Maglev system are all installed on the ground. No strict requirements for the volume, weight and anti-vibration of the equipment are available. Fig.11 Power supply overview It is the fundamental guarantee for the normal operation of the entire Maglev system. It includes all the equipment s to be used in security guarantee control, execution and plan and also includes the equipment to be used in communication among the equipment. IV. CONCLUSION Railways using MagLev technology are on the horizon. They have proven to be faster than traditional railway systems that use metal wheels and rails and are slowed by friction. The low maintenance of the MagLev is an advantage that should not be taken lightly. When you don t have to deal with the wear and tear of contact friction you gain greater longevity of the vehicle. Energy saved by not using motors running on fossil fuels allow more energy efficiency and environmental friendliness. Maglev will have a positive impact on sustainability. Using superconducting magnets instead of fossil fuels, it will not emit greenhouse gases into the atmosphere. Energy created by magnetic fields can be easily replenished. The track of a Maglev train is small compared to those of a conventional train and is elevated above the ground so the track itself will not have a large effect on the topography of a region. Since a Maglev train levitates above the track, it will experience no mechanical wear and thus will require very little maintenance. Overall, the sustainability of Maglev is very positive. Although the relative costs of constructing Maglev trains are still expensive, there are many other positive factors that overshadow this. Maglev will contribute more to our society and our planet than it takes away. Considering everything Maglev has to offer, the transportation of our future and our children s future is on very capable tracks. A magnetic levitation track is up and running at NASA s Marshall Space Flight Center in Huntsville, Ala, USA. The experimental track is installed inside a high-bay facility at the Marshall Center. Marshall s Advanced Space Transportation Program is developing magnetic levitation or Maglev technologies that could give a space launch vehicle a running start to break free from Earth s gravity. A Maglev launch system would use magnetic fields to levitate and accelerate a vehicle along a track at speeds up to 600 mph. The vehicle would shift to rocket engines for launch to orbit. Maglev systems could dramatically reduce the cost of getting to space because they are powered by electricity, an inexpensive energy source that stays on the ground unlike rocket fuel that adds weight and cost to a launch vehicle. IJTIMES-2018@All rights reserved 9

10 REFERENCES [1] Hyung.Woo Lee, Ki-Chan Kim, Ju Lee (2006) - Review of Maglev Train Technologies. IEEE Transaction on Mechatronics. [2] Kyura N. Ohoh (2008) - Mechatronics. IEEE/ASME Transaction on Mechatronics. [3] Vuchic VR, Casello JM (2002) - An evaluation of Maglev Technology & its comparison with High speed Rails. [4] David W. Russell (2010) - Mechatronic in Action: case studies in Mechatronics Application and Education. [5] Jens Hillebrand (2008) - The Magnetic Levitation Train A technology Ahead of its Time. [6] Bonsor, Kevin. How Maglev Trains Work. com/maglev-train.htm [7] Sau-ying. Ma Tong Shiu-Sing, Maglev Physics World, 24 March, [8] Tony R. Eastham, High speed Rail Scientific American, September [9] S. Yamamura, Magnetic Levitation technology of Tracked Vehicles presents status and prospectus IEEE Trans. Magn., Vol. MAG-12, Nov [10] P. Sinha, Design of magnetically levitate vehicle IEEE Trans. Magn., Vol. MAG-20. September IJTIMES-2018@All rights reserved 10