E-trailer
This page provides the steps on how to model e-trailer project from e-Traction. e-trailer project is a concept project from e-Traction in which e-trailer is a normal trailer that has an electric motor mounted to one of its axle.
The ultimate goal of this project is to increase energy efficiency [kWh/km] hence reducing operating cost.
Contents
Creating the simulation
All of the component modules used in this simulations can be downloaded from (insert e-trailer folder)
The first step in creating this simulation is the same as the example simulation for Parallel Hybrid vehicle simulation. Click here to learn more.
Test scenarios
The test scenarios that will be used for this simulation is the so-called WHVC (World Harmonized Vehicle Cycle).
To get the same result as the simulation result presented below, do not change any global surrounding environment variable inside the parameter_main file.
ECU
A simple control algorithm has been developed and implemented into the e - trailer model in order to control the energy distribution between the Internal Combustion Engine and the Electric Machine. The control algorithm used the accelerator and brake pedal position to determine the demanded torque by the vehicle so that it can follow the desired driving cycle. The amount of throttle and brake required was calculated by the driver model which also includes the gear shift logic that calculates the required gear number for a certain moment. The electric machine is used together with the I.C.E. to achieve the demanded torque when the ECU determined that the demanded torque is above the maximum capability of what the engine can supply. If the state of charge of the battery is lower than the minimum charge value, the electric machine will be used as a generator to charge the battery. The electric machine is also used for braking the vehicle when possible, however, mechanical brakes will be used when the braking from the electric machine is not sufficient.
The input signals to the ECU modules are:
| Subsystem | Input signal | Signal label | Retrieved from |
|---|---|---|---|
| Driver | Accelerator pedal position | Drv_AccPedl_Rt | Vehicle driver manual sensor |
| Brake pedal position | Drv_BrkPedl_Rt | ||
| Drive cycle reference speed | Drivecycle_RefSpeed_mps | ||
| Clutch pedal position | Drv_CluPedl_Rt | ||
| Requested gear number | Drv_nrGearReq | ||
| Plant model | Actual engine speed | Eng_nAct_radps | Engine sensor |
| Crankshaft torque | Eng_tqCrkSftAct_Nm | ||
| Indicated torque | Eng_tqindAct_Nm | ||
| Engine oil temperature | Eng_tOilAct_K | ||
| Battery output current | Batt_iAct_A | Battery sensor | |
| Battery output voltage | Batt_uAct_V | ||
| State of charge | Batt_socAct_Rt | ||
| Battery temperature | Batt_tAct_K | ||
| Clutch disengaged or not | Clu_flgConnected_B | Clutch sensor | |
| Electric machine output torque | ElecMac_tqAct_Nm | Electric machine sensor | |
| Electric machine output speed | ElecMac_nAct_radps | ||
| Electric machine output current | ElecMac_iAct_A | ||
| Electric machine output temperature | ElecMac_tAct_K | ||
| Transmission output speed | Transm_nOutAct_radps | Transmission sensor | |
| Transmission gear number | Transm_nrGearAct | ||
| Clutch lock | Transm_flgConnected_B | ||
| Transmission input speed | Transm_nInAct_radps | ||
| Vehicle velocity | Chassis_vVehAct_mps | Total vehicle speed | |
| Wheel speed | Chassis_nWheelAct_radps | Total wheel speed | |
| Vehicle mass | Chassis_massVehAct_kg | Total vehicle mass | |
| Road slope | Chassis_slopeRoad_kg | either chassis slope from Truck or Trailer since both of should be the same | |
| Auxiliary system output current | Aux_iAct_A | Electrical auxiliary sensor |
Plant model
The plant model for e-trailer project is split up into two group, those are the truck and the trailer.
The vehicle topology for e-trailer is similar to the Parallel Hybrid vehicle example. However, the electric motor in e-trailer is connected to the trailer wheel while the Parallel Hybrid vehicle connect the electric motor to the mechanical gear which connects both engine and electric motor together.
The input signals for truck component modules are:
| Module | Input signal | Signal label | Retrieved from |
|---|---|---|---|
| Internal combustion engine | Requested engine speed | Eng_nReq_radps | ECU cmd |
| Switch Speed / torque control | Eng_flgReqSwitch_B | ||
| Requested engine torque | Eng_tqReq_Nm | ||
| Exhaust brake ON / OFF | Eng_flgExhaustBrake_B | ||
| Engine ON / OFF | Eng_flgonoff_B | ||
| Starter motor ON / OFF | Eng_strtReq_B | ||
| Fuel cut off | Eng_flgFuelCut_B | ||
| Engine rotational speed | phys_speed_radps | Clutch mechanical fb output | |
| Clutch | Requested clutch pedal position | Clu_ratReq_B | ECU cmd |
| Clutch torque input | phys_torque_Nm | ICE mechanical output | |
| Clutch inertia input | phys_inertia_kgm2 | ||
| Clutch rotational speed input | phys_speed_radps | Transmission mechanical fb output | |
| Transmission | Requested gear number | Transm_nrGearReq | ECU cmd |
| Transmission torque input | phys_torque_Nm | Clutch mechanical output | |
| Transmission inertia input | phys_inertia_kgm2 | ||
| Transmission rotational speed input | phys_speed_radps | Final gear mechanical fb output | |
| Final gear | Final gear torque input | phys_torque_Nm | Transmission mechanical output |
| Final gear inertia input | phys_inertia_kgm2 | ||
| Final gear rotational speed input | phys_speed_radps | Chassis mechanical fb output | |
| Truck Chassis | Requested chassis brake torque | Chassis_tqBrake_Nm | ECU cmd |
| Chassis torque input | phys_torque_Nm | Plant model total vehicle torque | |
| Chassis inertia input | phys_inertia_kgm2 | Plant model total vehicle inertia | |
| Drivecycle slope | Chassis_slopeRoad_Rad | Test scenarios |
The input signals for trailer component modules are:
| Module | Input signal | Signal label | Retrieved from |
|---|---|---|---|
| Battery | Battery current input | battery | Plant model battery current input |
| Battery Actual cooling flow | Batt_flowActCooling_kgps | ECU cmd | |
| Electric machine | Requested electric machine speed | ElecMac_nReq_radps | ECU cmd |
| Switch speed / torque control | ElecMac_flgReqSwitch_B | ||
| Requested electric machine torque | ElecMac_tqReq_Nm | ||
| Electric machine actual cooling flow | ElecMac_flowActCooling_kgps | ||
| Electric machine voltage input | phys_voltage_V | Battery electrical output | |
| Electric machine rotational speed input | phys_speed_radps | Trailer chassis sensor | |
| Electrical auxiliary system | Requested power | Aux_pwrElecReq_W | ECU cmd |
| Voltage input | phys_voltage_V | Battery electrical output | |
| Trailer Chassis | Requested chassis brake torque | Chassis_tqBrake_Nm | ECU cmd |
| Chassis torque input | phys_torque_Nm | Plant model total vehicle torque | |
| Chassis inertia input | phys_inertia_kgm2 | Plant model total vehicle inertia | |
| Drivecycle slope | Chassis_slopeRoad_Rad | Test scenarios |
Driver
The e-trailer project use manual transmission, the drive manual module will be used as the driver model.
The input signals for the driver module are:
| Subsystem | Input signal | Signal label | Retrieved from |
|---|---|---|---|
| Plant model | Actual vehicle velocity | Chassis_vVehAct_mps | Plant model total vehicle speed |
| Transmission input speed | Transm_nInAct_radps | Transmission sensor | |
| Transmission actual gear number | Transm_nrGearAct | ||
| Clutch disengaged or not | Clu_flgConnected_B | Clutch module | |
| Driver | Accelerator pedal rate | Drv_AccPedl_Rt | Driver module |
| Drive cycle | Drive cycle time and speed | drivecycle_time_speed | Test scenario module |
