The third generation of rail transit traction technology has been successfully conquered

After 11 years, a total of 10 million tests, 150G data, and a cost of 100 million yuan, CRRC's Zhuzhou Electric Locomotive Research Institute Co.
, Ltd.
(hereinafter referred to as "Zhuzhou Institute") has conquered the third-generation rail transit traction technology, namely the permanent magnet synchronous motor traction system (hereinafter referred to as the "permanent magnet traction system"), mastered completely independent intellectual property rights, and become a major strategic weapon
for China's high-speed rail market.

On May 16, 2015, the permanent magnet synchronous motor used in Changsha Metro Line 1 was successfully delivered
.
This is the first time in China that the permanent magnet synchronous motor is loaded into the entire subway vehicle and put into loading application
.

Ding Rongjun, academician of the Chinese Academy of Engineering and general manager of Zhuzhou Institute, revealed that at present, Zhuzhou Institute has developed a 690kW permanent magnet traction system that can be used for high-speed rail trains with a speed of 500 kilometers per hour, and will be produced in small batches
.
This marks that China has become one of
the few countries in the world that has mastered the technology of high-speed rail permanent magnet traction system after Germany, Japan, France and other countries.

"China's permanent magnet traction system with completely independent intellectual property rights has taken the pace of industrialization, and the 'permanent magnet traction era' of China's rail transit has finally arrived
.
" Ding Rongjun said
.

From "for subway" to "for high-speed rail": "After climbing Hengshan and climbing Mount Everest"

The traction drive system is known as the "heart of the train" in the industry, and its performance determines the power quality, energy consumption and control characteristics of the train to some extent, and also affects the economy, comfort and reliability of the train, which is the key to
energy-saving upgrades.

The first generation of the world's rail transit vehicle traction system is the DC motor traction system, and the second generation is the AC asynchronous motor traction system that started in the 70s of the 20th century, which is the current mainstream technology
.

Feng Jianghua, deputy general manager of Zhuzhou Institute, introduced, "For rail transit traction technology, the permanent magnet traction system is a revolution, and whoever has the permanent magnet traction system has the right
to speak in high-speed rail.
”

Permanent magnet traction system is the power system of the train, composed of two parts: converter and motor, of which the converter is equivalent to the heart of the train, the motor is like the muscle of the train, the motor is mainly responsible for transmitting power, completing the transformation of electrical energy to mechanical energy, driving the train to run
smoothly.

At present, international equipment manufacturers such as Siemens and Bombardier have taken permanent magnet traction systems as their research and development direction
.
In this emerging field, China has not lost at the beginning
.

In 2003, the elaboration of the permanent magnet traction system first reached Feng Jianghua's ears
.
At that time, the technology was still in the theoretical research stage
.
However, Feng Jianghua realized that the permanent magnet traction system will replace the AC asynchronous motor traction system and must be developed
quickly.
In that year, Zhuzhou Institute took the lead in establishing the first permanent magnet traction system R&D team in China, "starting from scratch"
.

Xu Junfeng, deputy director of the Foundation and Platform R&D Center of Zhuzhou Institute, said that in the research and development stage of AC asynchronous motor traction system, China lagged behind foreign countries by more than 20 years; In the more advanced field of permanent magnet synchronization, "we are like a car without lights, groping on a mountain road with dark lights, a little uncertain direction, and the consequences are not just mistracking"
.

"Motor temperature control is the biggest bottleneck
in the progress of the project.
" Xu Junfeng introduced that in order to avoid water, dust, iron filings and other corrosion of the permanent magnet inside the motor, the motor adopts a fully enclosed structure, but because the motor power is too large and the heat generation is too high, the permanent magnet material may have a serious risk
of irreversible magnetic loss under the conditions of high temperature, vibration and reverse strong magnetic field.
"If the train loses magnetism at high speed, the consequences are unimaginable
.
"

Feng Jianghua recalled that "there was no information to learn from, and there was a lack of relevant equipment for R&D and testing", and Zhuzhou could only "cross the river by feeling the stones", and many data still had to rely on relatively primitive and stupid methods
.
"For example, the motor heating test is done for five or six hours, and the motor temperature control data is manually squatted throughout the whole process to record, so that it can slowly accumulate
.
" Feng Jianghua said
.

Eight years after the establishment of the R&D team, that is, at the end of 2011, the permanent magnet traction system of Zhuzhou Institute was successfully loaded on Shenyang Metro Line 2, realizing the first application in the field of domestic rail transit, ending the history
of China's railways without permanent magnet traction system.
Zhuzhou Institute has also become the only enterprise
in China that has mastered the complete set of independent permanent magnet traction system technology.
By the end of May 2015, Shenyang Metro Line 2 had operated 70,000 kilometers
of passengers without trouble.

"This time, we grabbed the top spot
.
" Feng Jianghua told reporters that in 2011, Zhuzhou was appointed to participate in the national "863 Plan" of the "key project of major key technology and equipment development of high-speed railway", and undertook the research and development of permanent magnet traction system for high-speed
EMUs.

From "small power" to "high power", from "subway" to "high-speed rail", Zhuzhou is facing new difficulties
.

Li Yifeng, chief design expert of Zhuzhou Institute, told China Economic Weekly that the power of the permanent magnet synchronous motor used in the Shenyang Metro is 190kW, and the motor power of the high-speed EMU with a speed of 500 kilometers per hour is as high as 690kW, and it is always in a high-speed operation state, which poses great challenges to the stability and reliability of the traction system.

Despite this, Zhuzhou Institute completed the task
ahead of schedule.
In December 2013, Zhuzhou Institute successfully developed a motor that can be used for high-speed rail bullet trains with a speed of 500 kilometers per hour, and in October 2014, it was successfully loaded and evaluated
in Qingdao Sifang Joint Stock Company.

"If it goes well, China's high-speed rail will soon be fully equipped with the permanent magnet traction system, which is not only more energy-efficient, but also more stable and safer
.
" Li Yifeng said
.

"Energy saving artifact": increase the power of high-speed rail motors by 60%

Ding Rongjun told China Economic Weekly that in 2014, Zhuzhou's traction system accounted for 57% of the urban rail train market, and will gradually replace the asynchronous motor system with a permanent magnet traction system
in the future.

Liu Kean, deputy general manager and chief engineer of Times Electric Company, a subsidiary of Zhuzhou, said: "High efficiency and energy saving are the most prominent advantages
of permanent magnet traction systems.
”

The data shows that the 690kW permanent magnet synchronous motor developed by Zhuzhou has 60% more power than the current mainstream asynchronous motor, and the motor loss is reduced by 70%.

According to the actual operation data of Shenyang Metro Line 2, Liu Kean calculated an account: a subway can save energy equivalent to 4 million yuan per year, "This is the profit, which one will not want to use it?" ”

An industry analysis report produced by Liu Kean shows that by 2020, about 100 urban rail transit lines
will be built across the country.
If 60% of the new lines adopt permanent magnet traction system, the expected output value will reach 10 billion yuan, and the annual energy consumption of new lines will save 240 million yuan
nationwide.

Permanent magnet systems also show strong alternative advantages
in the field of central air conditioning.
Central air conditioning based on permanent magnet variable frequency drive system can achieve energy saving of 40%.

A 240kW central air conditioner can save at least 115,200 kWh
of electricity a year if it runs for four months a year.
According to the calculation of 40,000 central air conditioners in the country, it can save 4.
6 billion kWh of electricity and reduce emissions of 460,000 tons of carbon dioxide
in one year.

Since the start of research and development in 2009, Zhuzhou Institute has successfully developed the world's first set of central commercial air conditioning permanent magnet high-speed direct drive system, becoming the only supplier
of central air conditioning permanent magnet drive system at home and abroad.
By the end of April 2015, more than 400 sets
of permanent magnet systems in Zhuzhou Institute had been applied to central air conditioning.
At the China Refrigeration Exhibition in April this year, Gree Electric Appliances introduced the central air conditioner equipped with permanent magnet synchronous frequency conversion heat pump centrifuge to the market
as its high-end product.

The high efficiency and energy saving of the permanent magnet traction system have enabled Zhuzhou to occupy the high point
of market competition in the fields of electric vehicles, wind power generation, and 100% low-floor modern trams.

Feng Jianghua said that the research and development and industrial application of permanent magnet traction system is still in its infancy, "In the future, on the one hand, Zhuzhou Institute will deepen and refine the research and development of technology vertically, and on the other hand, it will continuously expand the application field of permanent magnet traction technology horizontally to achieve a comprehensive layout and continuous leadership
.
" ”