By Li Xinping, People’s Daily
Prototypes of the CR450 bullet train, the world’s fastest high-speed train with a test speed of up to 450 kilometers per hour (km/h) and an operational speed of 400 km/h, were debuted in Beijing on Dec. 29, 2024.
The CR450 is significantly faster than the CR400 Fuxing high-speed trains currently in service, which operate at speeds of 350 km/h. Here are the secrets behind the higher speed.
Stronger Power
High-speed rail runs fast because it converts electrical energy into mechanical energy. The CR450, utilizing permanent magnet traction motors, has increased energy conversion efficiency by over 3 percent compared to the CR400, which uses asynchronous traction motors. The stronger power output enables the train to run faster.
Lower Resistance
As high-speed trains accelerate, aerodynamic resistance escalates exponentially with the velocity. When the speed rises to 400 km/h, the resistance will increase by 30 percent. This means that most of the energy generated by traction motors is expended in combating air resistance. With an innovative design, the CR450 has managed to slash operational resistance by 22 percent.
Lighter Weight
A lighter weight is crucial for high-speed trains. The CR450 has cut its weight by over 10 percent compared to the CR400, thanks to the adoption of new materials such as carbon fiber composites and magnesium alloys, as well as the topology optimization technique.
Better Performance
Apart from high speed, it is more important for bullet trains to have efficient braking. The CR450 now takes only 6,500 meters to achieve a complete stop from 400 km/h, the same braking distance as the CR400.
This outstanding performance has allowed the CR450 to reach a higher speed without increasing energy consumption. When running at 400 km/h, the eight-carriage CR450 consumes only 22 to 23 kilowatt-hours of electricity per kilometer, making it a cost-effective and eco-friendly choice for commercial operations.
The CR450 high-speed train also boasts many eye-catching designs.
More Intelligent
The CR450 is equipped with intelligent monitoring and diagnostic systems, which allow the train to collect data such as axle temperature and pressure from over 4,000 monitoring stations in real time. This advanced technology has enabled the train to recognize, assess and determine its actions by itself.
Besides, the CR450 has innovatively adopted time-sensitive network transmission signals, leading to a ten-fold increase in the efficiency of real-time data transmission. This has facilitated the communication among different systems on the train and enhanced the control precision.
Quieter Operation
The passengers’ level of comfort is greatly influenced by noise levels, which typically rise by two to three decibels for every 50 km/h increase in speed. The CR450 has managed to reduce its in-cabin noise by two decibels, making the overall noise level comparable to that of the high-speed trains currently in service, which operate at 350 km/h.
More Comfortable
The height of the CR450 has been trimmed from 4.05 meters to 3.85 meters to make the train more slender. Even with the reduction in the overall height, the height of the interior cabin remains unchanged. Thanks to this compact design, the CR450 offers 4 percent more room for passengers and has expanded the storage capacity for large luggage by 100 percent.
More functions
The CR450 is designed with adaptive lighting that can adjust brightness according to the outdoor environment, touchless restrooms with “airborne buttons,” and additional options like family compartments and multi-functional spaces.
“We are committed to providing passengers with diverse, convenient, and personalized services to enhance their travel experience,” said Ren Guangqiang, an executive with the Locomotive & Car Department of China Railway.
The CR450’s development represents China’s venture into new and unexplored aspects of the high-speed train industry.
China Railway launched research on basic theories and key technologies for high-speed trains operating at 400 km/h in 2018, followed by the beginning of development efforts in 2021.
In 2022, the company released overall technical specifications and extensively carried out simulation calculations and ground-based tests, including technical parameter tests on the Zhengzhou-Wanzhou and Jinan-Zhengzhou high-speed railways, and new technology component replacement tests on the Mile-Mengzi and Fuzhou-Xiamen high-speed railways. The production of prototype trains officially commenced in 2024.
According to Li Yongheng, an executive with the Department of Science, Technology and Information Technology of China Railway, the CR450’s successful completion was made possible with the data collected from the extensive track tests of over 200,000 kilometers, as well as over 1,000 simulation calculations and ground-based tests.
“For the first time in the world, the CR450 uses actual track tests to determine boundary conditions and confirm top-level indicators, thereby creating technical specifications based on actual requirements,” said Zhang Bo, head of the Locomotive & Car Research Institute of China Academy of Railway Sciences Corporation Limited.
Sources say that the R&D team of the CR450 has performed more than 100 experiments to explore how different parameters of the train are affected by the rising train speeds. They have gathered data features in different speed contexts and operating environments such as bridges, tunnels, and curves, laying a robust groundwork for the development of the CR450 high-speed train.
With the debut of the CR450 high-speed train prototypes, China has set a global precedent by establishing a standard system for the commercial operation of high-speed trains traveling at 400 km/h.
“The CR450 has demonstrated China’s overall capabilities in technological innovation and high-end equipment manufacturing,” said Li.
According to an official with China Railway, the company plans to conduct a range of line tests and assessments for the prototypes to further examine performance indicators, so as to expedite its entry into commercial operation.
