Automotive Electronic Differential System(EDS) Control Strategy And Technology Research

To ensure the wartime logistical needs, cross-country and the truck of military are requested a higher degree of performance. Electronic differential lock System(or EDS), which is based on the appendiculate conditions of the driving wheel, lock and unlock at appropriate time, give the vehicle full play to the ground friction and improve the vehicle performance through. Therefore, the research of EDS control strategy and technology have enormous significance to improve the mobility and capability in wartime troop transport capacity.This paper introduces the status at home and abroad of automobile differential lock and some methods of anti-skid control, analyses the advantages and disadvantages of these methods, analyses the transmission system structure for the EDS, and it establishes the vehicle dynamics model according to the engine, clutch, transmission, differential lock, and the tires for the automotive. On the basis of the model, this paper analysis and put forward the corresponding control strategy, that is, first of control the output power of engine (gasoline engine: to reduce fuel injection, ignition delay time, throttle position adjustment and the use of auxiliary air devices; Diesel: control the supply quantity and time of oil), when driving wheel slip ratio up to a certain limit, lock the larger differential one. Papers simulated automobile with two-wheel and single-wheel on based on fuzzy control by Simulink, completed structure design of the electronic control unit (ECU) and the differential lock mechanical through the analysis of the EDS demand, and completed structural design and control experiments and analysis for the differential lock based on step motor.Control strategy and technology research results of automotive electronic differential lock indicate that :(1)Mandatory lock-differential and self-locking differential has been little use in a variety of drive anti-skid ways because of its mechanical structure and mode of implementation shortcomings. Anti-skid control system (ASR) ,which have can more extensive use in the top grade small vehicle, combine with the Anti-lock Braking System (ABS), but it was restricted in the cross-country and the truck of military. EDS ,which have no noise, lock convenience; the characteristics of the strong drive, can overcome the shortcomings of mandatory lock-differential, self-locking differential and ASR; (2)EDS can locking differential lock attachment effectively coefficient in different road conditions when difference of wheel speed reach to the set limits, make a rational allocation of torque to each wheel, make full use of ground adhesion, drive the automobile start smoothly, improve drive anti-skid and off-road capability significantly on the special road .