Thales SelTrack

Karabük Üniversitesi Raylı Sistemler Mühendisliği Bölümü

Karabük Üniversitesi bu sene Raylı Sistem sektöründe yetkin bireyler yetiştirmek amacı ile yeni açtığı Raylı Sistemler Mühendisliği Bölümü'ne öğrenci kabul edecek. Sektörümüz için lisans düzeyinde açılan ilk program olması sebebi ile büyük mutluluk yaşıyoruz. Aslında bunun için Türkiye’de açılan ilk program demek çokta doğru olmaz. Yıldız Teknik Üniversitesi 1911 yılında “Kondüktör Mekteb-i Alisi” adıyla Fransızlar tarafından demiryolu mühendisi yetiştirmek amacıyla kurulmuştur. Fakat daha sonrada ülkemizde yürütülen politikalardan ve çeşitli nedenlerden ötürü üniversite misyon değiştirmiş ve bu günkü halini almıştır. Bugün bu sektör için yeniden mühendis yetiştirmeye başlayan Karabük Üniversitesini gerçekleştirdikleri bu büyük hizmet için kutluyoruz.

Bilindiği gibi Raylı Sistemler birçok branşın içinde bulunduğu bir sektördür. Yani tek bir bölüm okuyarak tamamen raylı sistem mühendisi olmak çok zordur. Avrupa'daki programlar da Raylı Sistemler Elektriği, Mekaniği, Elektro-mekaniği, Sinyalizasyonu, Araç Mühendisliği gibi dallara ayrılırlar. Karabük Üniversitesi bu çerçevede misyonlarında belirttikleri üzere tüm bölümlerden temel düzeyde eğitim vermeyi amaçlıyor. Fakat bizim düşüncemiz bu bölümde okuyan bir öğrencinin en geç 4. Dönem sonunda dal tercihi yapıp tek bir alanda uzmanlaşmasının gerektiğidir. Üniversite ve bölüm yetkililerinin bu yönde sektör ile birlikte çalışmalar yapmaları gerektiğini düşünüyoruz. Aynı şekilde bu bölümden mezun olan bir mühendisin Raylı Sistemler üzerine daha özel bir dalda yüksek lisans yapmasının gerekli olduğu yönündedir. Karabük Üniversitesinin ileriki senelerde bu yönde çalışma yapıp yüksek lisans programlarını da başlatmalarını diliyoruz.

Karabük Üniversitesi her ne kadar temel seviyede makine, elektrik-elektronik ve inşaat mühendisliği dallarında eğitim vermeyi amaçlıyor olsa da akademik programlarında çoğunlukla mekanik derslerine ağırlık verildiği görülüyor. Verilmesi amaçlanan bazı dersler ve branşları şu şekildedir:

Dersin Adı	Dersin Kredisi		Dersin Branşı
Statik	4	Makine
Bilgisayar Bilimlerine Giriş	3	Bilgisayar
Bilgisayar Programlama	3	Bilgisayar
Malzeme Bilimi	3	Makine
Dinamik	4	Makine
Termodinamik I	3	Makine
Fren Mekanizmaları	3	Makine
Tren Mekaniği	3	Makine
Mekanizma Tekniği	2	Makine
Mukavemet	4	Makine
Raylı Sistemler Elektrik Elektroniği	4	Elektrik Elektronik
Akışkanlar Mekaniği	3	Makine
Makine Elemanları	3	Makine
Mekanik Titreşimler	3	Makine
Isı Transferi	3	Makine
Mekatronik	3	Mekatronik
Ölçme Tekniği	3	Elektrik Elektronik
Taşıt Dinamiği ve Kontrol	4	Makine
Termodinamik II	3	Makine
Hidrolik Makinalar	3	Makine
Tren ve Demiryolları Bakım Esasları	4	İnşaat
Köprüler ve Tüneller	3	İnşaat
Demiryolu Haberleşmesi	3	Haberleşme
Malzemelerin Mekanik Davranışı	3	Makine
Taşıt Gövde Tasarımı ve Malzemeleri	4	Makine

Bunların dışında Raylı Sistemler Mühendisliğinin Temelleri, Transport Teknolojisi ve Ekonomisi,  Demiryolu Güvenlik Standartları, Demiryolları Araçlarının Testi ve Denetimi, Kent içi Raylı Ulaşım Sistemleri, Demiryolları Trafik Kontrolü, Genel Raylı Sistem İşletmeciliği, Demiryolu Hattı Planlaması  gibi Raylı sistemlere özel derslerde akademik programda yer alıyor. Ayrıca Lokomotif ve Vagon Tasarımı ve Sinyalizasyon gibi çok kapsamlı konuların işlendiği dersler de programa alınmış fakat bu derslere ayrılan süre oldukça az. Özellikle sinyalizasyon dersi haftada 2 saat işlenerek ancak “Sinyalizasyon Sistemlerine Giriş” şeklinde verilebilir.

Ülkemizde sektörümüzün tekrar canlandığını, mevcut kent içi ve şehirler arası hatlara hızlı bir ivmeyle yenilerinin eklendiğini, bu alanda seminer, sempozyum, fuar gibi etkinliklerin daha fazla yapıldığını, üniversitelerde daha fazla bilimsel makale yayınlandığını, büyük projeler geliştirildiğini ve raylı sistemlere özel bölümler açıldığını görmek bizlere çok büyük mutluluk vermektedir. Bu bağlamda Karabük Üniversitesi Raylı Sistemler Mühendisliği Bölümü’ne ve bu bölümde okuyacak mühendis adaylarına şimdiden başarılar diler, bölümümünüz ülkemize hayırlı olmasını dileriz.

http://muh.karabuk.edu.tr/raylisistemler/

Mustafa Bellek

Future Signalling

MULTIPLE UNIT OPERATION

Introduction

Originally derived from lift operation over a hundred years ago, multiple unit (MU) control has become the most common form of train control in use around the world today.  This page describes how it started and its development in the century to date.

See also Electric Traction,  Electric Traction Drives,  Electric Traction Glossary and Electronic Power.

Contents

Origins - The Relay - The Contactor - Multiple Unit Control - Forward and Reverse

Origins

Electric locomotives were originally designed so that the motors were controlled directly by the driver.  The traction power circuits passed through a large controller mounted in the driving cab.  A handle was rotated by the driver as necessary to change the switches in the circuit to increase or reduce power as required.  This arrangement meant that the driver had to remain close to the motors if long and heavy, power-carrying cables were to be avoided. 

While this arrangement worked well enough, the desire to get rapid turnrounds on city streetcar railways led to the adoption of remote control.  The idea was that, if the motors could be remotely controlled, a set of driver's controls could be placed at each end of the train.  It would not be necessary to have a locomotive added at the rear of an arriving train to allow it to make the return journey.  A cab would be installed at each end of the train and the driver just had to change ends to change direction.  Once this idea was established, it was realised that the motors could be placed anywhere along the train, with as many or as few as required to provide the performance desired.  With this development, more but smaller motors were scattered along the train instead of building a few large motors in a locomotive.   This is how the concept of motor cars and trailer cars evolved.  Trailer cars are just passenger carrying vehicles but motor cars are passenger carrying vehicles which have motors and their associated control equipment. 

Multiple unit trains, as these trains became known, were equipped with control cables called train lines, which connected the driver's controls with the motor controls and power switches on each motor car.  The opening and closing of the power switches was achieved by electro-magnetic relays, using principles originally designed for lifts.  While the idea was being established on passenger trains, it was also adopted on locomotives.  It quickly became the standard method of control.

Full article: http://www.railway-technical.com/muops.shtml

Basic Model of a Wheelset, Degrees of Freedom

For more than 150 years, the wheel – rail system has provided a relatively safe system of transport. This safety level is so high that the mechanism is generally neglected and considered as a simple slider by most people.
However, the engineer’s point of view can be different, especially when taking into account responsibilities in a railway network. The wheel – rail contact is actually a complex and imperfect link. Firstly, it is a place of highly concentrated stresses. The conical wheel shape makes the wheelset a mechanical amplifier, limited by the transverse play, with partially sliding surfaces. The contact surfaces are similar to those in a roller bearing but without protection against dust, rain, sand, or even ballast stones.

If the track is considered to be rigid, then the railway wheelset has two main degrees of freedom:

• The lateral displacement, or shift, y
• The yaw angle, a

When the behaviour of a wheelset is unstable, the dynamic combination of these two degrees of
freedom is called “hunting.”
The lateral displacement and the yaw angle must be considered as two small displacements relative to the track. The play will be the limit of the lateral displacement between the two flange contacts. It is generally approximately +-8 mm.
The other degrees of freedom are constrained: the displacement along Ox and the axle rotation speed v around Oy are determined by the longitudinal speed Vx and the rolling radius of the wheel r0 with: Vx ¼ vr0: The wheelset centre of gravity height z and the roll angle around Ox are linked to the rails when there is contact on both rails.
The railway wheelset is basically described by two conical, nearly cylindrical wheels (Figure 1 and Figure 2), linked together with a rigid axle.

Figure 1 Wheelset degrees of freedom.

Figure 2 Rail, wheel and contact frames.

Each wheel is equipped with a flange, the role of which is to prevent derailment. In a straight line the flanges are not in contact, but the rigid link between the two wheels suggest that the railway wheelset is designed to go straight ahead, and will go to flange contact only in curves. This is the railway dicone or wheelset.
The interface between the wheel and the rail is a small horizontal contact patch. The contact pressure on this small surface is closer to a stress concentration than in the rest of the bodies. The centre of this surface is also the application point of tangential forces (traction and braking Fx, guiding or parasite forces Fy, see Figure 1). The knowledge of these forces is necessary to determine the general wheelset equilibrium and its dynamic behaviour.
In order to determine this behaviour and these forces, the first thing to do is to determine some contact parameters: the contact surface, the pressure and the tangential forces. This determination is generally separated into two steps:

1. The normal problem (Hertz theory)
2. The tangential problem (Kalker’s theory)

Relay Based Interlocking System

General Schema

Relay Sequence Chart

MAGLEV Trains

Mass Transit is by no means a new idea - railroads have been around since 1829, and we've been riding trains ever since. Although new technology allows us to ride faster and more comfortably, the basic idea is the same: a locomotive of some sort pulls or pushes a string of cars along a metal railway. But now, after over one hundred years of faithful service, the old railroad systems are being retired. A new system is making its mark on the world, and its name is MagLev.

MagLev, or magnetic levitation, trains are the newest and brightest form of Mass Transit. The technology has already been implemented in Germany and Japan, and although it was researched and proposed, it never really took hold in the United States. The German version of the MagLev train, called Transrapid, opened in 1989, the same year as the Japanese MLU002 began running. The little-used American version is called Inductrack. Each of these trains uses a different type of MagLev technology.

Before going into that, however, one should understand the fundamental concepts behind MagLev trains. A MagLev train is called that for a very good reason - the train cars use gigantic magnets to hover above their tracks, decreasing the negative impact friction has on a train's speed and allowing the cars to achieve much greater speeds than normal railroad cars.

There are two different types of magnetic levitation used in MagLev trains - electrodynamic suspension (EDS) and electromagnetic suspension (EMS). Judging by name alone, EDS and EMS don't sound very much different, but in reality they are as opposite as night and day.

EDS uses the repulsive force between superconducting magnets mounted in the vehicle and other conducting magnets in its "U"-shaped guideway to keep the vehicle levitating. EDS technology is more expensive than other methods, since it requires that permanent magnets be installed in the track and the vehicle; still, it is safer, since guide wheels can be installed in case something goes wrong, and vertical, roll, pitch, lateral, and yaw motions are all more stable and easily controlled in an EDS train. The Japanese MLU002 is an example of EDS technology in action. The Japanese chose it for its safety, reduced energy losses, and lighter vehicles, and were able to use cheaper materials to reduce costs.

EMS, on the other hand, utilizes the attractive force of magnets by wrapping the bottom of the vehicle around the track and mounting magnets in the part of the vehicle that's below the track. This way, the electromagnets underneath are attracted to the track, made of a ferromagnetic substance (i.e., a regular magnet made of something similar to iron), and just enough energy is put into the electromagnets to keep the vehicle hovering around the track.

A MagLev train using the EMS system pulls itself along the track with a linear synchronous motor (LSM), which, in simple terms, uses the electromagnetic currents in the vehicle to attract it to the track ahead of it, so that the vehicle is drawn further along the track. The speed is adjusted by changing the frequency of the electromagnetic fields pulling the vehicle.

The drawback to using EMS technology is that vertical, roll, and pitch motions must be controlled by other electromagnets outside the vehicle. Also, EMS trains are slightly less safe, since they have no guide wheels to catch the vehicle in the event of a malfunction or power failure. However, they are cheaper, since the track need only be a sizeable chunk of ferromagnetic material. One example of a MagLev train using EMS technology is the German Transrapid, choosing EMS for its rapid development and certification time. The trains are designed to operate at speeds of 250 to 310 mph, and although the design is more complicated and expensive, it consumes 30% less energy than other MagLev trains and can carry up to 1,060 passengers in a ten-section set.

There is one final type of magnetic levitation technology that is used solely in the American version of MagLev, known as Inductrack. Inductrack employs what is known as a Halbach Array, or a set of large, powerful bar magnets arranged very carefully, so that an enhanced magnetic field is generated below the array, but none above it. Also, the array of magnets acts like a coiled spring - as the distance between the array and the track decreases, the levitating force increases exponentially, so that no matter how heavy the cars are, they will still hover above the track. Halbach Arrays are mounted on the bottom of Inductrack vehicles, and electromagnetic coils placed in the track help generate even more magnetic force. Inductrack trains are inherently stable and, since they use permanent magnets, they require very little power. As stated earlier, the American Inductrack is the only type of MagLev train that uses Halbach Arrays, and although it seems like a very good idea, Inductrack is not very prevalent in America.

To compare mass transit to air travel, railroad cars are like propeller planes, and MagLev trains are like Boeing jets. MagLev trains are faster, vastly more efficient, definitely more environment-friendly, and safer than traditional trains, airplanes, and automobiles. The newest hit in mass transit is here, and its name is MagLev.

Demiryolu Anklaşman Sistemi:

Demiryolu anklaşman sistemi (Railway interlocking system) bir istasyon içerisindeki ve komşu istasyonlar arasındaki trafiği kontrol eden sistemdir. Bu kontrol tren rotalarını, makas tanzimlerini ve diğer bütün raylı sistem araçlarının hareketlerini demiryolu kurallarına, düzenlemelerine ve işletmedeki demiryolu istasyonunun teknolojik süreç gereksinimlerine uyarak gerçekleştirilir.

Anklaşman Mantığı: Anklaşman mantığı (Interlocking Logic) terimi raylı sistemlerde makaslar, sinyaller, ray devreleri vb. gibi sahada kullanılan fiziksel birimlerin birbirleri arasındaki mantıksal ilişkiyi ifade eder. SSI sistemlerinde bu olgu yazılım içerisinde programlanır. Röle tabanlı anklaşman sistemlerinde ise rölelerin birbirleri ile uygun şekilde bağlanarak oluşturulan kumanda devreleri ile elde edilir. Sinyal levhalı anklaşman sistemlerinde fiziksel komponentlerin birbirlerine mekanik mafsallarla uygun bir şekilde bağlanmasıyla anklaşman mantığı oluşturulur.

Anklaşman Çeşitleri:

Mekanik Anklaşman Sistemi (Ground-frame Interlocking): Sistemler arasında mekanik bağlantılar kullanılarak gerçekleştirilen anklaşman sistemleridir. Mafsallar ve tellerden oluşan sistem en eski anklaşman örneğidir. Günümüzde kullanım alanı yoktur.

Röleli Anklaşman Sistemi (Route Relay Interlocking System - RRI): Tamamen tanzim rölesi (Route Relay) denilen elektro mekanik röleler ile gerçekleştirilen anklaşman sistemidir.

Elektronik Anklaşman Sistemi (Solid State Interlocking System - SSI): Diğer tipteki sistemlerde kullanılan mekanik mafsallar veya elektromekanik röleler yerine elektronik ekipmanların kullanıldığı anklaşman sistemleridir.

Interlocking

Interlocking: Means an arrangement of signals , points and other appliances, operated from a panel or from lever frame, so interconnected by mechanical locking or electrical locking or both that their operation must take place in proper sequence to ensure safety.

Essentials of Interlocking:
-It shall not be possible to take “OFF” a running signal, unless all points including isolation are correctly set all facing points are locked and all interlocked level crossing gates are closed and locked against road traffic for the line on which the train will travel, including the overlap.

-After the signal has been taken “OFF” it shall not be possible to move any points or lock on the route including overlap and isolation, nor to release any interlocked LC gate until the signal is replaced to the “ON” position.

-It shall not be possible to take “OFF” at the same time any two fixed signals which can lead to any conflicting movements and

-Where feasible points shall be so interlocked as to avoid any conflicting movement.

Ramazan Bellek: Şifrelemenin Kanunları - Bölüm 1.2

Ramazan Bellek: Şifrelemenin Kanunları - Bölüm 1.2: "1.3 Kümeler Bir küme, herhangi iki elemandan eşsiz bir üçüncü elemanı türetmek için bir ikili işleme (binary operation) sahip bir takım küm..."

AC Lokomotif Diyagramı