Wednesday, December 27, 2023 · 0 min read
How Did They Do It? Testing the World's Fastest Train
The Shanghai Maglev Train, also known as the Shanghai Transrapid, is a maglev (magnetic levitation) train. It was developed in Germany for use in China by Transrapid International. It’s a joint venture of Siemens and ThyssenKrupp, two top German engineering companies. There are faster trains in development, but as of this writing, with a top operating speed of 431 km/h (268 mph), Shanghai Transrapid is currently the fastest commercially operated train in the world.
From a standstill, it takes only four minutes for Shanghai Transrapid to reach its top speed. It was designed to connect the Shanghai Pudong Airport with the Longyang Road interchange station, 30.5 km (18.9 miles) away. Amazingly, it covers this distance in about eight minutes.
Shanghai Transrapid basic facts
Type: Transrapid SMT (based on the German TR 08)
Trains in service: 3
Cars/wagons per train: 6
Total length: 153.6 m (504 ft.)
Width: 3.7 m (12.14 ft.)
Height: 4.2 m (13.78 ft.)
Max. authorized speed: 505 km/h (314 mph)
Passenger capacity: 574 (End section - ES - 1st class: 56; Midsection - MS - 2nd class: 110; End section - ES - 2nd class: 78)
What are the fastest trains on Earth?
Passengers can ride commercially on these high-speed rail demons in Asia, Europe, the Middle East, and northern Africa:
|Typical Max. Speed*
|430 km/h (268 mph)
|CR400 Fuxing Line
|350 km/h (217 mph)
|330 km/h (205 mph)
|E5 Bullet Trains
|320 km/h (199 mph)
|320 km/h (199 mph)
|320 km/h (199 mph)
|310 km/h (193 mph)
|305 km/h (189 mph)
|300 km/h (186 mph)
|300 km/h (186 mph)
|300 km/h (186 mph)
How does magnetic levitation work?
Shanghai uses Electromagnetic Suspension (EMS) for levitation and propulsion. EMS uses the attractive force between electromagnets on the vehicle and a conductive track on the guideway to levitate the train and maintain a constant gap while travelling at high speed.
The train is equipped with powerful electromagnets. When an electric current is passed through these magnets, it generates a magnetic field. The guideway contains a conductive material that interacts with the magnetic field of the electromagnets on the vehicle.
The interaction between the magnetic field of the electromagnets and the conductive track creates an attractive force, lifting the vehicle above the track. The vehicle's height above the track can be controlled by adjusting the amount of current passing through the electromagnets. The height is usually about 1 cm (~0.39 inches).
There is another type of suspension called Electrodynamic Suspension (EDS), which uses the repulsive force between magnets on the vehicle and magnets on the guideway to achieve levitation. EDS requires super-cooled, superconducting electromagnets. These electromagnets are more expensive to make and maintain than the ones used in EMS systems, but they can continue to conduct electricity even after a power loss. Japan’s maglev trains are based on EDS.
To compare, EMS relies on the attractive force between electromagnets and a conductive track, while EDS uses the repulsive force between permanent magnets to achieve magnetic levitation. Early in the development process, EMS was chosen for the Shanghai Maglev train.
EMS Maglev trains levitate thanks to electromagnets of similar poles fitted under the train and on the bottom of the T-shape guideway that the train floats above. The magnets repel each other, thus creating a gap between them and allowing the train to stay suspended. about 1 cm (~0.4 in.) above the guideway and keeps the train levitated even when it's not moving. Additional magnets located throughout the train help to keep it stable during travel.
Maglev trains have fewer moving parts than conventional wheeled trains, which means less noise and maintenance, but they require that new guideways (tracks) be built, which is a considerable expense. According to Wikipedia, the Shanghai Maglev trains, elevated guideways, and stations cost $1.33 billion. From end to end the system is 30.5 kilometres (19.0 miles), resulting in a cost of $43.6 million per kilometre.
A video showing the Shanghai Maglev train starting at the station
Do Maglev trains have wheels?
EMS Maglev trains have small auxiliary wheels that allow the train to move along the guideway when it is unpowered, but the train does not roll on them during normal operation.
However, EDS maglev trains like the ones in Japan levitate higher above the guideway than EMS trains. EDS trains roll on these wheels until the superconducting magnets on the bogies begin to interact with the guideway’s magnets. When an EDS maglev train reaches 150 kph (93 mph), the magnetic field lifts the train 10 cm (~4 in.) above the guideway, and the wheels are no longer in contact with the guideway.
Once there is no more physical contact, speed can be increased dramatically. When an EDS train’s speed decreases, the body is lowered until the wheels make contact again and the train rolls on them as it slows and comes to a stop.
In addition, some maglev trains are designed to deploy these auxiliary wheels as a mechanical braking system to augment the magnetic system if needed.
The Shanghai Maglev project
Shanghai Transrapid began routine operations in late 2003. However, it took years of development and testing to reach this milestone.
The German engineering companies Siemens and ThyssenKrupp formed a joint venture in the 1970s called Transrapid. They built a series of maglev trains over the years, which were used around the world, but they were not typically high-speed trains.
The government of China hired Transrapid to develop a high-speed maglev to connect the Shanghai Pudong Airport with the Longyang Road Station and thus born the Shanghai Transrapid high-speed line. Transrapid was also in charge of system integration and testing, ensuring that the train’s systems and subsystems worked seamlessly together. The Transrapid 08-type maglev trains were built in Germany.
Building the guideway
Based on German and Chinese technology, a dedicated elevated guideway was designed and built in Shanghai. The guideway provides the magnetic levitation and propulsion required by the train. The guideway requires steel with low magnetic permeability, otherwise, it may create energy-draining eddy currents.
In addition to the electrical concerns, the guideway had to be built to precise dimensional specifications. The line itself is operated by SMTD Shanghai Maglev Transportation Development Co., Ltd.
18 guideway sections were built in the Chinese city of Kassel, as well as 124,000 stators to be mounted on the guideway. ThyssenKrupp Transrapid built the motor windings that were installed within the stators.
Eight flexible steel girders for the switches were manufactured and fitted out by Krupp Stahlbau Hannover. Switch control units and motor windings were outsourced. The guideway, comprised of girders, substructures, and foundations, was built by the Chinese, with the consultation of the German guideway consortium. Everything was installed in Shanghai by Chinese personnel working under the guidance of Transrapid.
Testing the world's fastest commercial train
Shanghai Transrapid was tested extensively before it was put into service with paying passengers. The testing program included both laboratory and on-track testing.
Wind tunnel testing
Aerodynamics is a critical area of study for every vehicle, from cars and trucks to aircraft, spacecraft, and trains. Shanghai Transrapid was tested in a wind tunnel to measure its drag and lift coefficients, as well as the effect of crosswinds.
Noise and vibration tests
As with any vehicle, tests were performed to measure and mitigate unpleasant noise and vibrations generated by the train during operation. Vibrations are also important to evaluate to ensure that the structure’s natural frequencies are not excited to the point of causing mechanical failures.
There are two related and yet fundamentally different testing methodologies used:
NVH (noise, vibration, and harshness) testing and
Comprehensive safety testing involves simulating various scenarios to evaluate the responsiveness of safety features. Crash tests and emergency simulations are conducted to ascertain the train's behavior under extreme conditions, ensuring that safety measures are effective in protecting passengers and minimizing risks.
The seamless integration of various subsystems and components is crucial for the overall functionality of every kind of train. Integration tests were conducted to verify that all systems worked cohesively. During this process, compatibility or functional problems are identified and corrected.
Shanghai Transrapid operates primarily outdoors, in all kinds of weather and temperatures. The train cars were subjected to extreme temperature and environmental testing to ensure their resilience and longevity. This included evaluating resistance to weather conditions and wear caused by environmental elements as well as the HVAC system’s ability to provide a comfortable environment for the passengers.
Following a series of low-speed tests, high-speed tests were conducted on the same guideway to assess Shanghai Transrapid’s overall performance at typical operating speeds. Of particular interest were acceleration and deceleration. How fast could she reach her top cruising speed, and how fast could she safely decelerate and come to a stop?
Efficient propulsion and reliable braking are critical components of the functionality of every train, especially very fast ones. Tests focus on evaluating the propulsion system's acceleration, deceleration, and overall efficiency.
A train’s ability to increase and decrease speed under a wide range of passenger loads and operating conditions must be tested against the engineering models created during the design phase and according to the operational specifications of the governing authority. Acceleration and vibration are measured using accelerometers, displayed in real-time during testing, and stored digitally for offline analysis.
During testing, the Shanghai Transrapid was pushed to 501 kph (311 MPH) to evaluate its performance during extreme speed conditions. Speed data could be obtained from the train itself, as well as via external sensors. These measurements provided critical information about the movements of the train under all conditions.
Dynamic operating tests were performed to evaluate how Shanghai Transrapid would handle curves in the tracks, uneven tracks, or even unexpected changes in the track’s magnetic field. Test runs were conducted on the guideway during operation using measuring instruments and sensors to capture these results for online observation as well as deeper off-line analysis
Brake tests are an integral part of dynamic tests. The full range of emergency braking tests was performed to ensure that Shanghai Transrapid would handle both normal operation braking as well as emergency braking events. The ability of rail vehicles to remain stable during emergency situations is important for obvious reasons.
One of the fundamental aspects of Maglev technology is its ability to levitate above the guideway and maintain stability on all three axes. Engineers conducted extensive tests to verify that the magnetic levitation system could effectively counteract gravitational and inertial forces, ensuring a smooth and stable ride. System performance was tested under various loads and speeds.
Reliability and endurance tests
The Shanghai Maglev was subjected to extensive reliability, endurance, and structural testing. Simulating long-term operation, the train was run continuously for extended periods during which its critical systems were monitored continuously. Afterwards, critical components were inspected for signs of wear, fatigue, or damage.
When testing trains, ballast is used in the train to simulate the weight of actual human passengers and luggage. This ballast is sometimes in the form of actual crash test dummies like automobile makers use.
However, if testing the effects on human physiology isn’t necessary, simpler and less expensive barrels filled with water are used. This ballast is distributed around the train where the passengers would be. For example, in the USA, the rail industry considers a “standard passenger” to be 175 lbs (79.38 kg).
Tests with passengers
Finally, it was time for test runs with actual passengers. These tests were used to get direct feedback from passengers about their experiences so that any necessary final adjustments could be made.
In today’s typical testing scenarios, comprehensive baselines are created using objective measurements from data acquisition instruments. This is followed by subjective assessments provided by human beings.
The combination of these outputs allows engineers to perform train validation. The goal is always to have safe vehicles which also provide a comfortable experience for the passengers.
Future faster trains
Even faster trains are in development that will move to the top of this list once they are fully operational. Here are just a few of them:
The Japanese L0 series SC (superconducting) maglev train is planned to run at 500 kph (311 mph). It is expected to start going into service in 2027. During performance testing in 2015, L0 set a world speed record for a train, reaching 603 km/h (375 mph).
Japan’s upcoming Chuo Shinkansen line will connect Tokyo and Nagoya. It will use EDS Maglev (Magnetic Levitation) technology. Travel time between the two cities will be reduced by approximately 50% compared to today’s Tokaido Shinkansen line. The line will be extended eventually to Osaka.
Japan has been at the forefront of maglev technology since the 1970s. Reportedly JR Central is financing the Chuo Shinkansen SC maglev line without the use of any public money.
In China, the Qingdao CRCC 600 maglev train has been designed to travel at 600 km/h (373 mph). Its typical operational maximum speed has not been announced, but the train is expected to begin entering service in 2025.
Qingdao was developed by CRRC Qingdao Sifang Co in the port city of Qingdao, a subsidiary of China Railway Rolling Stock Corporation headquartered in Beijing, the world's largest rolling stock manufacturer by annual production volume.
China licensed Transrapid technology from the German engineering company ThyssenKrupp. It will be China’s first multicity high-speed maglev train, expected to be faster than even air travel between many cities when considering all aspects of the commute. These trains are either wholly or mostly funded and controlled by the Chinese government.
As of this writing, full-scale high-speed testing of the CRCC 600 is limited by the lack of long guideways to run them on. Guideways of at least 50 km are needed to get the train up to full speed for any length of time.
In the meantime, scientists and engineers are developing complex finite element models to simulate stress, strain, vibration, and load on critical components such as the swing bars. According to a 2022 report in the International Journal of Mechanical System Dynamics, multi-body system simulation (MBS) is being used to evaluate train dynamic performance at 600 kph speeds.
What about the USA?
Due to the United States’ well-known preference for automobile and air travel, it has lagged behind the rest of the world regarding high-speed rail travel. However, the busy “northeast corridor” that spans from Boston through New York City to Washington DC has long been the country’s busiest route and national carrier AMTRAK runs a combination of regular and high-speed passenger trains called Acela.
Acela currently runs up to 241 km/h (150 mph), but only on a fraction of the length of the northeast corridor. This is due to traffic and the limitations of track infrastructure. Amtrak has contracted with Alstom to build a new fleet of cars called Avelia Liberty that will be operated up to 257 km/h (160 mph), scheduled for operation starting in 2024.
A company called Northeast Maglev has bigger aspirations: to build a high-speed maglev system to connect Washington DC to first Baltimore, then to New York City. Traffic in this busy corridor is bad and getting worse every year, so such a system could make a positive impact.
The company reports that the average Washington, DC commuter spends 102 hours/year in traffic, costing each commuter $2,060 per year, adding up to $6.3 billion per year. At 300 mph (482 km/h) the time between the main northeast cities would be reduced to one hour. The project is under development but is still years in the future. Interestingly, JR Central has been in discussions with the Americans about the possibility of providing Shinkashen trains for this line.
The Shanghai Transrapid project was spearheaded by two of the world’s most experienced train manufacturers from Germany in cooperation with their Chinese customers. A rigorous testing process ensured that the train would meet all required safety standards. Combined with finite element modelling, objective physical testing demonstrated the train’s reliability and efficiency before it was officially opened to the public in 2003.
The proof is in an extremely high safety record. In 20 years of operation, there have only been a few safety incidents and no injuries. In 2006 there was an electrical fire in a car as the train was leaving Pudong station. In 2011 there was an equipment failure that caused an operating delay of approximately one hour.
As a result of good engineering, rigorous testing, and ongoing maintenance, Shanghai Transrapid has been a reliable and remarkably safe train.