C. C. Chan
University of Hong Kong
Hong Kong, China
AsianScientist (Mar. 2, 2018) – As Tesla’s electric cars turn heads and capture news headlines around the world, it is worth remembering that an Asian scientist was among the pioneers of electric vehicle technology. Professor C. C. Chan, the founding president of the World Electric Vehicle Association and the founding director of the International Research Center for Electric Vehicles (IRCEV), is known for being the first to use an alternating current (AC) motor in electric cars.
Chan’s influence on the electric vehicle scene goes back almost five decades and spans the globe. During the oil crisis in the 1970s, the US announced the electric and hybrid vehicles act, calling upon automobile manufacturers to conduct research on electric vehicles. A test center for electric vehicles was established in Hawaii, but the research program languished due to a lack of local expertise.
At that time, Chan was already a published author of several papers on electric vehicles, and so the Americans sought his expertise. He was more than happy to collaborate, even proceeding to establish the IRCEV to foster closer ties among the global research community to accelerate electric vehicle development. The IRCEV still exists within the University of Hong Kong today.
Over the years, Chan has written over 400 technical papers and 11 books and has been granted 10 patents, which are licensed by various Japanese and Chinese industries. His many accolades include the Medal of Engineering Excellence by the World Federation of Engineering Organizations and the Guanghua Engineering Science and Technology Prize which is the highest prize of the Chinese Academy of Engineering.
But beyond the technicalities of electric vehicle motors, Chan has also devoted much thought to issues of sustainability, as well as the intimate connection between energy systems and information.
In this interview with Asian Scientist Magazine, Chan recounts his humble beginnings and explains his vision for electric vehicles in the future.
- What inspired you to become an electrical engineer?
I think it was because in the years following World War II, there was an air of urgency to rebuild, and engineering seemed to be the most exciting field to be in. Of the various engineering disciplines, electrical engineering was most exciting to me because energy is required for living and electricity is the most important secondary source of energy—once you convert primary energy sources such as oil, gas or sunlight into electrical energy, it is the most efficient and easy to control and use. Electrical engineering therefore contributes to food, health and other important aspects of life; that was what attracted me to it.
- Why did you decide to start working on electric vehicles?
My interest in electric vehicles was inspired by my father. He was running a bus and taxi business in Java, and I remember wandering into the garage after school. There, I saw that there was oil and smoke emitting from the vehicles, and all the workers were very dirty. The vehicles looked nice when they were on the roads, but in the garage they were really ugly.
So I wondered if it was possible to have cars without the oil and smoke. I didn’t know the answer back then, of course. Then I went and did my bachelor’s degree in electrical engineering at the China University of Mining & Technology and I learnt that there were battery-operated cars in the mines to transport coal. I learnt about electric traction, and I understood that vehicles didn’t need to run by internal combustion engines—electric motors were a possibility.
However, I also realized that the drawback of electrical motors would be that the energy storage density of batteries was limited. The driving range and charging time were both big problems in the efficiency of electrical vehicles.
Only recently have lithium batteries come into the picture, making electric motors more feasible, and I myself am leading a project on next-generation electric power sources that use lithium-sulfur batteries which could double the storage capacity of existing technologies.
- You pioneered the AC motor driving system. What is the significance of this?
Any motor requires a field as motors are based on Faraday’s laws, that is, the interaction of a current and a field. In a direct current (DC) motor, the field comes from an exciting current, and therefore controlling the speed of the motor is easy.
In a DC motor, the exciting current produces the field, while the armature produces torque. But in an AC motor, the input current encompasses both the field component and the torque component—they cannot be split, so you have less control over speed. The advantage of the AC motor, however, is that it is simple, cheap and rugged.
Then in 1957, German engineers found that they could split the AC current into two components using microprocessors, and this was used to develop computers and many other electronics. But people didn’t realize that these microprocessors could be applied in the motor industry.
My contribution thus lies in the development of core principles that bring together these elements to create the AC motor driving system. I have four rules that are not patented but they have been published in my book with the Oxford University Press, which are essential for the creation of an electric motor.
In summary, you need a high power density, good torque-speed characteristics, a high efficiency regardless of torque and speed, and lastly, reasonable cost. You must meet these requirements from the electromagnetic point of view, and at the same time, you must consider the mechanical resilience of the motor and a cooling system.
- What are some of the remaining limitations in the electric vehicles industry?
The electric vehicles industry is now in the beginning of the commercialization stage in China, and we can expect exponential growth. China now leads the world in terms of the number of electric vehicles on its roads.
But whether this growth can be healthy growth remains to be seen. The first big challenge is the range of electric vehicles. Typically, current battery technology is capable of 200 Watt hours per kilogram. Charging requires several hours, and for every charge, an electric vehicle can travel less than 200 kilometers. In contrast, for gasoline cars, you only need a few minutes for refueling to travel hundreds of kilometers.
The second challenge lies in the price of electric vehicles. If you look at the whole life cycle of a product, electric vehicles are cheaper. But the initial cost of these vehicles is really high, beyond what some people can afford.
While subsidies may help alleviate this situation, they only push production capacity, not the improvement of technology. For example, in China, the subsidies are so high that the car manufacturers do not have the incentive to improve the technology.
- How might some of the challenges facing electric vehicles be overcome?
On the technology front, improvements are still needed for the chassis and the core of electric vehicles. The chassis must be lightweight and strong, because then you require less power. For the core, improvements can be made to the electric motor, the electric battery and the electric control system. Among the three, the battery is the most important—we can push the envelope with lithium sulfur batteries and solid-state lithium batteries.
I also think that increasing the variety of electric vehicles is important. You need citizen cars that are inexpensive, safe and reliable for short distance travel. You also need family cars, like SUVs, which can take more passengers. Then you should have high performance luxury cars, as well as electric public transportation vehicles, such as taxis and buses.
But in addition to better technology and more variety, policies and market-driven approaches are also necessary to increase the adoption of electric vehicles. Without policies in place, electric vehicles may struggle to become mainstream. But without paying attention to market forces, the push for widespread adoption electric vehicles will not be sustainable.
So you need a good product, good infrastructure and good business models. An example of infrastructure would be charging stations, and a possible business model would be car sharing. What you need to create is an ecosystem to support electric vehicles.
It is also important to acknowledge that electric vehicles are not just a means of transportation. They are important carriers of energy within a larger energy system. This is because of the electric car battery, which allows the two-way flow of energy: you can charge it at night, but in the day, the vehicle could be used to charge appliances in the home, or even deliver power to the grid. Moreover, vehicles are carriers of information and culture, which means that you can have the integration of transportation, energy, information and humanity.
- What keeps you motivated teaching and doing research at your age?
Well, I ask myself what should I do in this world? And I am particularly inspired by the crest of Harvard University, upon which is written ‘veritas’—truth.
I feel compelled to find the truth for the betterment of society. To find the truth, you must have curiosity and do research to discover things. It’s challenging but also exciting and rewarding, especially when the work has impact on future generations. Problems like urbanization, aging populations, climate change, sustainable energy and new diseases are global grand challenges, and I think it is rewarding to be involved in facing these grand challenges.
- What advice do you have for younger scientists?
First of all, they must have curiosity. But more than that, they must have foresight and learn from history. They must understand what society needs and also the grassroots needs. At the same time, they must have an awareness of developments around the world, both in the East and in the West.
In addition to these, they should pay attention to six I’s. Inspiration and imagination are important, which enable innovation. Then there needs to be integration—of academia and industry, and of policy, technology and talent, the market, finance and culture. After that, implementation and investment are essential.
This article is from a monthly series called Asia’s Scientific Trailblazers. Click here to read other articles in the series.
Copyright: Asian Scientist Magazine; Photo: C. C. Chan.
Disclaimer: This article does not necessarily reflect the views of AsianScientist or its staff.