"Permanent magnetic core" will invigorate Hong Kong's "smashing car"
Hong Kong's trams, commonly known as "smashing cars", have been in Hong Kong since 1904 and have a history of more than 100 years. They are still favored by Hong Kong citizens and tourists. They travel daily on the streets of Hong Kong and are full of vitality. One of the most important reasons is that it has a "core" that is always young. This "core" was upgraded by Yongji Electric Company of China CRRC.
On January 28, 2016, the permanent magnet traction system developed by CRRC Yongji Motor Company for Hong Kong Tram passed the assessments of Beijing Jiaotong University, Southwest Jiaotong University, China CRRC-related units and Hong Kong Tramways Co., Ltd. The conclusion of the expert review shows that the system design has reached the advanced level of the domestic electric drive system and has the conditions for loading and commissioning.
The first electric drive system of the Hong Kong electric train was a DC electric drive system powered by a DC motor. In 2008, Yongji Electric Company designed the AC asynchronous electric drive system according to the requirements of the Hong Kong Tram Company. It improved the system volume, traction power and maintenance scheme while greatly improving the reliability of the system. The first AC asynchronous electric drive system was delivered to the user in April 2009. This is also the first time that a hundred years of "smashing cars" have undergone a thorough upgrade of the electric drive system. Up to now, Yongji Electric has provided 71 sets of asynchronous traction systems for Hong Kong Tramways, which fully maintains the vitality of “brakes”.
With the increase of online vehicles for AC asynchronous systems, the grid capacity of Hong Kong Electric Railway DC Power Station is gradually unable to support more AC asynchronous systems running online at the same time. To this end, in early 2015, Yongji Electric Co., Ltd. began to develop a more efficient and energy-saving AC permanent magnet electric drive system for Hong Kong trams. At present, the system completes the prototype trial, type test, ground joint adjustment test and through expert review, will carry out the loading operation assessment.
At present, only a few companies such as Alstom of France have experience in mass application of permanent magnet traction technology, and the development of domestic traction permanent magnet synchronous motor and permanent magnet electric drive system is still in its infancy, and has not been applied to the city rail car. field. Hong Kong Tram Permanent Magnet Electric Drive System is a new product developed by Yongji Electric Company in the field of railcars after mastering permanent magnet control technologies such as electric vehicles and marine propulsion systems.
Permanent magnet motors have obvious advantages such as small size, light weight, high efficiency, low noise, stable speed and high reliability, and are more suitable for urban rail vehicles. A large number of research and operation examples at home and abroad show that its advantage in urban transportation is that it is highly efficient and energy-saving. Under the same operating conditions, the permanent magnet traction system can save more than 20% energy compared with the asynchronous traction system. Increased as the regenerative braking performance increases. With the current Hong Kong tram running 10 hours a day, the journey is about 120 kilometers, the annual power consumption of the asynchronous traction system is 50,000 degrees, and the assembled permanent magnet traction system can save at least 9000 degrees per year.