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In the context of global energy instability caused by the transformation of global demand for energy and energy resources, one of the most important areas in the automotive industry is the development of electric vehicles. Serial production of high-tech electric vehicles with a long range contributes to the stabilization of the energy market and the sustainable development of the whole fuel-energy sector. To evaluate the possibility of optimizing the electric vehicles energy consumption, various regenerative braking strategies are discussed in the article based on the Nissan Leaf electric vehicle, which simulation model includes submodules of the traction electric motor, hybrid braking system, traction rechargeable battery and tires. In order to test the adequacy of the simulation model to reproduce the relationship between the operating parameters of electric vehicles various systems and evaluate their ability to regenerate energy during braking the simulation results were compared with the actual experimental data published by the Lab Avt research laboratory (USA). The relative error of the mathematical modeling results of the braking energy regeneration processes is 4.5 %, which indicates the adequacy of the electric vehicle simulation model and the possibility of its using as a base for research and comparison of the energy efficiency of various regenerative braking strategies. As the results of experiments have shown, the usage of the proposed control strategy of the regenerative braking maximum force allows increasing 2.14 times the energy recharging traffic to the battery as compared with the basic control strategy of fixed coefficient braking forces distribution with an increase in braking distance by 10 m. An alternative control strategy of regenerative braking optimal efficiency as compared to the basic control strategy provides a reduction in braking distance by 13.2 % at increasing by 84.4 % the amount of energy generated by the electric motor for recharging the batteries. The carried out investigations confirm the available significant potential for improving the efficiency of the electric vehicles usage by developing the control strategy and algorithms of the braking energy regeneration.

To ensure quality of dry friction clutch engagement in automated mechanical transmission during vehicle starting-up and maneuvering the control range of clutch actuator has to be maximum wide. It depends on the consistency of the clutch actuator geometric parameters with the electrical characteristics of the used solenoid valves, the output stage of the controller and the PWM control signal frequency. In addition to precision electronic control the driver must be able to “manually” operate the dry friction clutch in emergency. That is why friction clutch must have two independent control circuits. The original automated drive with a duplicate pneumohydraulic circuit for the friction clutch is presented in the paper, as well as the research results of the PWM frequency influence on operating range of the clutch pneumatic actuator. The research was based on the analysis of semi-natural experiment for assessing the functional performance of the designed automated mechatronic control system for the truck mechanical transmission. Ecomat R360 controllers were used as a hardware base of the test bench information control system. The developed software for the controller with one-parameter feedback on the clutch release lever movement allows to provide the PWM signal of varying duty ratio to the proportional solenoid valve of the automated drive. A graphical representation of the research results was performed with visualization possibilities of CoDeSys V2.3. During the semi-natural experiment, the polynomial dependence between variation of the clutch actuator control range and the generated PWM signal frequency in the range up to 400 Hz was revealed as well as practical recommendations on the choice of the optimum PWM signal frequency are also given in activity. The research results can be used in an adaptive control algorithm for automated mechanical transmission of trucks and road trains to ensure precise control of the clutch actuator in the starting-up and maneuvering processes.

The article presents a schematic diagram of the Euro-3 diesel engine electronic control and describes hard- and software platform of the high pressure fuel pump pneumatic actuator control that allows to realize the concept of electronic fuel supply control of diesel engine KamAZ-740. The strategic dependence beetwen the angular position of fuel pump governor lever and the angular position of electronic accelerator pedal were put on the basis of electronic control concept. Implementation of this dependence was carried out by applying a modulated PWM signal with determined duty cycle by the controller to the coil proportional solenoid valve, which is responsible for the amount of air pressure in the working chamber of the power air cylinder, connected by articulated-type to the governor lever of the high pressure fuel pump. In this case, the feedback control by position of governor lever of the high pressure fuel pump was introduced in the control circuit, but engine crankshaft speed control was carried out using a software continuous PID governor. Developed strategy gives possibility to track the deflection of control parameter from a predetermined value by real-time and almost instantly, to make a control action on actuators to eliminate this deflection, while providing a minimum time of transition. Governor’s setting (proportional, integral and differential component) performed empirically using the classical Ziegler – Nichols method, based on the analysis of the safety factor of automatic control system. The results of calculating the coefficients of proportional integral-differential regulator and oscillograms HIL experiment on testing the proposed diesel engine throttle control strategies using visualization CoDeSys V2.3 are given in activity.

The paper presents a schematic diagram of the powertrain automated control system based on dry friction clutch and manual gearbox. Mechatronic system has a modular configuration and allows to make the vehicle starting-up, low speed maneuvering and command or automatic gearshifting. Diesel engine, clutch and 10-step gearbox control is carried out at all movement modes by electronic modules when affected on mode selector, accelerator pedal and, if necessary, on brake pedal. Data exchange between electronic units is carried by SAE-J1939 protocol with a transmission rate of 250 kbit/s. Change in diesel fuel supply, clutch engagement and gearshifting take place automatically as a result of pneumatic power actuator operation by a signal from the controller to the corresponding solenoid valve or a combination thereof.Presents the results of semi-natural experiment on research of gear shifting process in the command mode of powertrain control. Transient gearshift oscillograms with various control algorithm structure have been given in the paper. The paper contains a ^iT^rative analysis of the oscillograma and a conclusion on expediency of gear shifting automation. A graphic representation of the semi-natural experiment results has been performed with the help of CoDeSys V2.3-visualization facilities.

Designed duplex actuator of friction clutch provides independent operation of two control circuits by using twin-lever declutching unit of original design. The invention allows to enhance mechatronic system reliability by preserving function on clutch control in case of electronics failure, energy carrier absence or its leakage from feeding/controlling mains. The paper provides an oscillogram that contains recording of road-train start-up process from standstill when a power plant operates in automatic mode. Such oscillogram proves operational capability of the designed automatic actuator with friction clutch.

The paper deals with an efficiency estimation of automated mechanical transmission at off-line simulation stage. A simulation model of a vehicle with an automated power unit for gear change control strategy research has been developed in the paper. The paper contains a complex mathematical description of the analysis scheme. It allows adequately to react to structure reorganization and parameter change of the dynamic system at an application of external disturbances from the road and a driver. A peculiar feature of the developed software that is an opportunity of real-time modeling. This decision enables to estimate automated mechanical transmission operation at a wide spectrum of the driver’s actions. The experiment on a driving simulation of a heavy truck with 40000 kg GCW on a road climb has been carried out. The estimated values of driving on a route have been compared during gear changes in automatic and command modes by drivers of various qualification. The paper contains conclusions about efficiency of the analyzed gear change control strategy. A strategy for improvement of automated mechanical transmission controlling algorithms has been proposed in the paper.