Tham khảo tài liệu 'understanding automotive electronics 5e episode 10', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | DIGITAL ENGINE CONTROL SYSTEM 7 11. The secondary air management system is used a. to control EGR b. to avoid knock c. with low-octane fuels d. to improve performance of the catalytic converter 12. When knock is detected in a closed-loop ignition system spark timing is a. initially advanced then retarded slowly b. always advanced to BDC c. retarded then advanced d. none of the above 13. Secondary functions of a digital engine control system may include a. evaporative emissions canister purge b. torque converter lockup c. secondary air management d. all of the above 14. In a direct electronic ignition control system a. the distributor is not required b. spark plugs are not needed c. the coil is not needed d. none of the above UNDERSTANDING AUTOMOTIVE ELECTRONICS 259 VEHICLE MOTION CONTROL 8 Vehicle Motion Control Electronic controls can automate some driver functions that were previously performed manually. A cruise control is a closed-loop system that uses feedback of vehicle speed to adjust throttle position. The previous chapter discussed the application of digital electronics to engine control. This chapter discusses the application of electronics to vehicle motion control systems such as cruise control tire slip control ride control antilock braking and electronic power steering control. TYPICAL CRUISE CONTROL SYSTEM Automotive cruise control is an excellent example of the type of electronic feedback control system that was discussed in general terms in Chapter 2. Recall that the components of a control system include the plant or system being controlled and a sensor for measuring the plant variable being regulated. It also includes an electronic control system that receives inputs in the form of the desired value of the regulated variable and the measured value of that variable from the sensor. The control system generates an error signal constituting the difference between the desired and actual values of this variable. It then generates an output from this .
