Existing and increasing electrical equipment
"There has to be a better way to start a car than by hand," at least that's what your great-grandparents thought. Electric starter motors have become an integral part of cars. These remain the most powerful electric motors besides the traction motor. With the advent of idle-stop technology and mild hybrid vehicles, starter motors are transforming into starter generators and taking on more functions. In some designs, enhanced starter motors can be used to "creep" while driving after parking, blurring the lines between starter motors and electric traction motors.
Windshield wipers are perhaps the most common example of electric motor application in modern automobiles. Every car has at least one wiper motor for the front wipers. Rear window wipers are increasingly popular in SUVs and cars with hatchback tailgates, meaning that rear wipers and their corresponding motors are present in most cars. Another motor pumps washer fluid to the windshield, and in some cars, it pumps it to the headlights, which may have their own small wipers.
Almost every car has a blower to circulate air through the heating and cooling systems; many vehicles have two or more fans inside the cabin. High-end vehicles also have fans installed in the seats for cushion ventilation and heat distribution.
Want to know where the electric motor is? The power seats are the perfect place to find it. In economy cars, the motor provides convenient fore-and-aft adjustment and backrest tilt. In luxury sedans, the motor controls height adjustment, seat cushion tilt, lumbar support, headrest adjustment, and seat cushion stability. Other seat features that use electric motors include powered seat folding and powered loading of the rear seats.
In the past, car windows were often opened and closed manually, but now electric windows are common; future generations will not understand why people used to use traditional round handles to lower their windows.
Each window houses a concealed electric motor, including variations such as sunroofs and rear windows found on minivans. The actuators used for these windows can be as simple as relays, but safety requirements (such as detecting obstacles or clamping objects) necessitate the use of more intelligent actuators with motion monitoring and drive force limiting.
The shift from manual to electric locks has made car locks increasingly convenient. The advantages of electric control include convenient features like remote operation, and enhanced safety and intelligence features such as automatic unlocking after a collision. Unlike power windows, electric door locks must retain a manual operation option, which influences the design of the electric door lock motor and its structure.
Indicators on dashboards or clusters may evolve into light-emitting diodes (LEDs) or other types of displays, but now every dial and instrument uses a small electric motor. Among the kinds of conveniences offered, other electric motors include common features such as folding and position-adjustable side mirrors, as well as more stylish applications such as convertible roofs, retractable running boards, and glass partitions between the driver and passenger.
Under the hood, electric motors are becoming increasingly common in other areas as well. In many cases, electric motors are replacing belt-driven mechanical components. Examples include radiator fans, fuel pumps, water pumps, and compressors. There are several advantages to changing these functions from belt-driven to electric drives. One advantage is that drive motors using modern electronics are more energy efficient than those using belts and pulleys, resulting in benefits such as improved fuel efficiency, reduced weight, and lower emissions. Another advantage is that using electric motors instead of belts allows for greater freedom in mechanical design, as the mounting locations of pumps and fans are not limited by the constraints of connecting serpentine belts to every pulley.
Technology Trends
Most electric motors in today's cars use a standard 12V automotive system, employing a belt-driven alternator to generate voltage and storing it in lead-acid batteries. This setup has been good for decades, but the latest vehicles require more comfort, entertainment, navigation, driver assistance, and safety features.
Dual-voltage 12V and 48V systems can move some high-current loads away from 12V batteries. The advantages of using 48V power are a four-fold reduction in current for the same power output, along with lighter cables and motor windings. Applications with high-current loads that may be upgraded to 48V power include starter motors, turbochargers, fuel pumps, water pumps, and cooling fans. Installing a 48V electrical system for these components could potentially save approximately 10% on fuel consumption.
Brushed DC motors are the traditional solution for driving most electrical convenience functions in a car body. These motors are simple to drive and relatively inexpensive because the brushes provide commutation. In some applications, brushless DC (BLDC) motors offer a significant advantage in power density, resulting in lighter weight and better fuel economy and lower emissions. Manufacturers have chosen BLDC motors for windshield wipers, cabin heating, ventilation, and air conditioning (HVAC) blowers and pumps. In these applications, the motors tend to operate for extended periods rather than for momentary use like power windows or power seats, where the simplicity and cost-effectiveness of brushed motors remain advantageous.
in conclusion
So, how many electric motors does your car have? You'd be hard-pressed to find a new car with fewer than a dozen electric motors, while a typical modern car on American roads likely has 40 or more. The increasing prevalence of electric vehicles will spur innovation in automotive electric motors. However, electric motors are already very common in ICE-propelled vehicles, and with their application being updated every model year, they make these applications more convenient, with better intelligent systems and a safer operating environment, while reducing environmental impact. We still have a lot of room for development.
