Konstrukce a automatizace zkušebního stanoviště

Abstract

Chemnitz University of Technology has been involved since 2018 in an academic automotive championship gathering 1:10 fuel cell/battery-powered vehicles. The goal of the race being to travel the longest distance with a limited amount of hydrogen and electricity, it would be meaningful to predict the vehicle fuel consumption prior to the race for a given driving style. For this purpose, the present work proposes a new approach which consisted in designing a chassis dynamometer allowing to implement race driving cycles and to emulate the related road load thanks to a real time industrial automation PLC software. In particular, the chassis dynamometer was designed with PTC CREO and is composed of four trunnionmounted hub dynamometers whose power absorption is performed by hysteresis brakes. The four modules can be controlled independently to adapt the type of 1:10 vehicle powertrain and are controlled from sequences that are implemented by using TwinCAT 3. The data acquisition system from Beckho Automation based on the real time eld bus EtherCAT has enabled the system to be tested under high transient driving cycles. The work has resulted of a chassis dynamometer capable of assessing the vehicle speed from 0 to 30 km=h with an accuracy lower than 3%. The vehicle battery voltage can be measuredin the range 0 to 10 V with an uncertainty lower than 0.1 %. Moreover, the test bench allow to compute the wheel's torque with a proper stability but considering a long delay between the reference torque value and dynamometer response. Finally, a driving cycle has been implemented and the vehicle associated to the PID controller has showed a response time lower than 80 ms.

Chemnitz University of Technology has been involved since 2018 in an academic automotive championship gathering 1:10 fuel cell/battery-powered vehicles. The goal of the race being to travel the longest distance with a limited amount of hydrogen and electricity, it would be meaningful to predict the vehicle fuel consumption prior to the race for a given driving style. For this purpose, the present work proposes a new approach which consisted in designing a chassis dynamometer allowing to implement race driving cycles and to emulate the related road load thanks to a real time industrial automation PLC software. In particular, the chassis dynamometer was designed with PTC CREO and is composed of four trunnionmounted hub dynamometers whose power absorption is performed by hysteresis brakes. The four modules can be controlled independently to adapt the type of 1:10 vehicle powertrain and are controlled from sequences that are implemented by using TwinCAT 3. The data acquisition system from Beckho Automation based on the real time eld bus EtherCAT has enabled the system to be tested under high transient driving cycles. The work has resulted of a chassis dynamometer capable of assessing the vehicle speed from 0 to 30 km=h with an accuracy lower than 3%. The vehicle battery voltage can be measuredin the range 0 to 10 V with an uncertainty lower than 0.1 %. Moreover, the test bench allow to compute the wheel's torque with a proper stability but considering a long delay between the reference torque value and dynamometer response. Finally, a driving cycle has been implemented and the vehicle associated to the PID controller has showed a response time lower than 80 ms.