In recent years the rapid development of China's automobile industry, domestic car sales in 2009 exceeded 13 million, marking China as the world's automobile production and the consumer.
Noteworthy is that car ownership in China's current 80 million, is expected in 2020 China's car ownership more than 2 million by 2030 may be close to the level of developed countries, reaching 450 million. Therefore,glue stick the fuel market, there is a huge gap in demand and supply, in a sense, the sustainable development of China's automobile industry depends on new energy vehicles, especially electric vehicles.
The development of electric vehicles depends on the development of core technologies, namely batteries, electric motor drive and vehicle development. In the classification of electric vehicles on the basis of its development should focus on electric vehicles, the demand for the motor drive technology, efficient, digital and integrated into vehicle motor drive system technology trends.
Any electric car needs motor.
Electric vehicles including electric vehicles, hybrid electric vehicles and fuel cell electric vehicle categories, glue gun the power system structure shown in Figure 1.
Pure electric vehicles to provide power from the battery, motor vehicle drive system through the DC converter PWM frequency and amplitude modulation becomes available to the controlled AC motor torque generated by the motor through the gearbox driving electric vehicle movement. Bottleneck of pure electric vehicles is battery technology. The most promising energy-based electric vehicle battery is a lithium iron phosphate batteries, lithium iron phosphate battery safety, and energy density of 80 ~ 120wh/kg, cycle life is expected to reach 2,000 times per watt by 2012 when the costs could be reduced to 1.0 ~ 1.5 million, or a driving range of 200 km of electric vehicle battery costs can be controlled at 3 million. So far, Nissan introduced the Leaf pure electric vehicles, BMW introduced the MINIE, our government and car manufacturers have attached great importance to the development of pure electric vehicles, including FAW, Chery, Beijing Automotive, etc., in China's major automobile manufacturers 2010 Beijing Auto Show, have launched a pure electric vehicle prototype.
Hybrid electric vehicles have two power sources: internal combustion engine and motor, the hybrid electric vehicle power system, including internal combustion engines and motor, the structure is more complex. Wide range of efficient and effective use of the motor can be the characteristics of four-quadrant operation, when the resistance is large to provide the impetus by the motor, the resistance-hour use of electrical power generation, so that optimal efficiency of internal combustion engines have been working in the area, improve the energy efficiency of the system. Therefore, the internal combustion engine hybrid electric vehicle is not only smaller than normal internal combustion engine vehicle emissions, and reduce energy consumption by 5% to 50%. PRUIS example of Toyota, PRUIS with a 1.5 liter engine, but its dynamic performance equal to or even higher than the 2L ordinary internal combustion engine vehicles, from the well to wheels efficiency from 16 to 18% to 32%. So far, the cumulative sales of Toyota hybrid has more than 200 million units, marking the hybrid electric vehicle into the mass market.
Fuel cell electric vehicles using proton exchange membrane fuel cell power generation system, the fuel is hydrogen vehicle fuel and oxygen in the air, hydrogen and oxygen to produce electricity and water after chemical combination, so the fuel cell electric vehicle is a zero-emission electric vehicles. In the fuel cell electric vehicles, fuel cell power has given voltage range, poor dynamic response characteristics, it usually takes a DC - DC converter (DC-DC) step-up, regulators, and battery together motor drive system power supply.
60,70 Since the last century, the United States and other Western countries to fuel cells for military and aerospace applications to civilian power generation and as cars, submarines, and other sources of power, the world's leading automotive companies have invested significant human and material resources to carry out fuel cell electric Development of the car. These efforts in 2002 to 2003 and reached a peak. June 2002, held in Canada in the 14th World Hydrogen Energy Conference, presented by the leading fuel cell products for the concept of hydrogen energy society.