Increasing fuel economy of commercial transport by using a hybrid power train

2020 ◽  
Vol 12 (2) ◽  
pp. 158
Author(s):  
E.S. Meltsyn ◽  
A.A. Markina
Author(s):  
E. S. Meltsin ◽  
◽  
A. A. Markina ◽  
A. V. Ilin ◽  
◽  
...  

The issue of increasing the fuel cost effectiveness of passenger commercial vehicles is one of the most important, since the annual increase in the fuel cost leads to an increase in the fixed costs of not only transport companies, but also of small- and medium-sized businesses. Using a hybrid power train (HPT) can reduce fuel consumption in the urban cycle, which is important for commercial vehicles used to deliver goods and passengers within the city limits, especially when megacities are involved, where traffic is heavy and average speeds are not high. The cost of cars with a hybrid power train, such as Toyota Prius, Lexus RX 450h, Ford Fusion Hybrid and others, remains quite high and does not allow to pay back the car only due to fuel economy. On the other hand, the configuration of these vehicles does not allow them to be used as a commercial vehicle for transporting small loads and passengers, Therefore, it is proposed to consider the option of converting a car with a gasoline engine and calculate the possible fuel economy.


Chapter 10 presents the principles of the plug-in hybrid power train (PHEV) operation. The power trains of the battery-powered vehicle (BEV – pure electric) are close to the plug in hybrid drives. For this reason, the pure electric mode of operation of the plug in hybrid power train is very important. The vehicle’s range of driving autonomy must be extended. It means the design process has to be focused on energy economy, emphasizing electricity consumption. Simultaneously, the increasing of the battery’s capacity causes its mass and volume also to increase. Generally, it is not recommended. After many tests, one can observe the strong dependence between the proper multiple gear speed, the proper mechanical transmission adjustment, and the vehicle’s driving range, which in the case of the plug-in hybrid power train means long distance of a drive using the majority the battery’s energy. The mechanical ratio’s proper adjustment and its influence on the vehicle’s driving range autonomy is discussed in the chapter. Three types of the automatic mechanical transmission are depicted: the toothed gear (ball), the belt’s continuously variable transmission, and the planetary transmission system called the “Compact Hybrid Planetary Transmission Drive,” equipped additionally with tooth gear reducers, connected or disconnected by the specially constructed electromagnetic clutches. The number of mechanical ratios—gear speeds—depends on the vehicle’s size, mass, and function, which in the majority of cases means the maximal speed value.


Chapter 9 is devoted to simulation research showing the influence of changes of the power train’s parameters and control strategy on the vehicle’s energy consumption, depending on different driving conditions. The control strategy role is to manage how much energy, frankly speaking, how much of the torque-speed relations referring to the power alteration, are flowing to or from each component. In this way, the components of the hybrid power train have to be integrated with a control strategy, and of course, with its energetic parameters to achieve the optimal design for a given set of constraints. The hybrid power train is very complex and non-linear to its every component. One effective method of system optimization is numerical computation, the simulation, as in the case of the multivalent suboptimal procedure regarding the number of electrical mechanical drive’s elements, whose simultaneous operation is connected with the proper energy flow control. The minimization of a power train’s internal losses is the target. The quality factor is minimal energy, as well as minimal fuel and electricity consumption. The fuel consumption by the hybrid power train has to be considered in relation to the conventional propelled vehicle. First of all, the commonly chosen statistic driving cycles should be taken into consideration. Unfortunately, this is not enough. The additional tests as for the vehicle’s climbing, acceleration, and power train behavior, referring to real driving situations, are strongly recommended during the drive design process.


Chapter 4 presents an approach to obtain the power simulation model of electric machines that would be practically useful in hybrid power train simulation studies. The induction motor (AC) and the permanent magnet motor’s (PM) mathematical dynamic models are based on the necessary and fundamental knowledge conveyed in the previous chapter. These generic models are here adapted to the hybrid power train requirements, while the mechanical characteristics of the vehicle’s driving system are relegated to the background. The vector field oriented control of induction and permanent magnet motors is applied in the conducted mathematical modeling. The influence of the controlled voltage frequency is discussed as well. In the case of permanent magnet motors, the adjusted method of magnetic field weakening is very important during pulse modulation (PWM) control. The chapter presents the model of synchronous permanent motor magnetic field weakening. The basic simulation studies’ results dedicated especially to the above-mentioned electric motors are included. One of the targets of these simulations is the determination of these electric machines’ static characteristics (motor’s map) as the function: output mechanical torque versus the motors’ shaft rotational speed. This feature is indicated as the map of electric machines connected with its efficiency in a four quarterly operation (4Q), which means the operation of the motor/generator mode in two directions of the shaft rotational speed, which appears very useful in practice.


The hybrid power train is a complex system. It consists of mechanical and electrical components, and each of them is important. The evolution of the Hybrid Electric Vehicle (HEV) power trains is presented from the historical point of view. This chapter discusses the selected review of the hybrid power train’s architectural engineering. It includes the development of the hybrid vehicle power train’s construction from the simple series and parallel drives to the planetary gear hybrid power trains. The fuel consumption difference between the pure Internal Combustion Engine (ICE) drive and the hybrid drive is especially emphasized. Generally, there are two main hybrid drive types that are possible to define. Both these hybrid drive types are not mainly differentiated by their power train architecture. The first is the “full hybrid” drive, which is a power train equipped with a relatively low capacity battery that is not rechargeable from an external current source, and whose battery energy balance—its State-Of-Charge (SOC)—has to be obtained. The second one is the “plug in hybrid,” which means the necessity of recharging the battery by plugging into the grid when the final State-Of-Charge (SOC) of the battery is not acceptable. Additionally, the chapter focuses on the fuel cell series hybrid power train, which is only shown because its operation and design are beyond the scope of this book.


2020 ◽  
Vol 10 (22) ◽  
pp. 8310
Author(s):  
Nicu Bizon ◽  
Mihai Oproescu ◽  
Phatiphat Thounthong ◽  
Mihai Varlam ◽  
Elena Carcadea ◽  
...  

In this study, the performance and safe operation of the fuel cell (FC) system and battery-based energy storage system (ESS) included in an FC/ESS/renewable hybrid power system (HPS) is fully analyzed under dynamic load and variable power from renewable sources. Power-following control (PFC) is used for either the air regulator or the fuel regulator of the FC system, or it is switched to the inputs of the air and hydrogen regulators based on a threshold of load demand; these strategies are referred to as air-PFC, fuel-PFC, and air/fuel-PFC, respectively. The performance and safe operation of the FC system and battery-based ESS under these strategies is compared to the static feed-forward (sFF) control used by most commercial strategies implemented in FC systems, FC/renewable HPSs, and FC vehicles. This study highlights the benefits of using a PFC-based strategy to establish FC-system fueling flows, in addition to an optimal control of the boost power converter to maximize fuel economy. For example, the fuel economy for a 6 kW FC system using the air/fuel-PFC strategy compared to the strategies air-PFC, fuel-PFC, and the sFF benchmark is 6.60%, 7.53%, and 12.60% of the total hydrogen consumed by these strategies under a load profile of up and down the stairs using 1 kW/2 s per step. For an FC/ESS/renewable system, the fuel economy of an air/fuel-PFC strategy compared to same strategies is 7.28%, 8.23%, and 13.43%, which is better by about 0.7% because an FC system operates at lower power due to the renewable energy available in this case study.


Author(s):  
Shekaina Justin ◽  
Samia Larguesh ◽  
Wafaa Shoukry ◽  
Ghada Naif Alnemer ◽  
J Shermina

2013 ◽  
Vol 300-301 ◽  
pp. 327-332
Author(s):  
Guo Liang Wang ◽  
Ji Ye Zhang ◽  
Xiao Hui Xu ◽  
Ming Li

A new hybrid power system with the “power grid-battery-ultracapacitor” was presented. The coupling relationship between the new hybrid power system and train driving was studied on the basis of considering the coupling relationship between train dynamics and the new hybrid power system. A traction simulation system was established. It could be used for traction simulation calculation on hybrid power train. It provided support for dynamics analysis of the new hybrid power train, design and optimization of the new hybrid power system and optimization of the train operation. In the end, traction simulation calculation for hybrid power train was done with actual line. The calculation results provided strong support for the development of the hybrid power train.


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