Panu Sainio

Hardware-in-the-loop verification environment for heavy-duty hybrid electric vehicles

This paper presents an implementation of a versatile hardware-in-the-loop verification environment for heavy-duty hybrid electric vehicle (HEV) control software development. The verification environment is located at university facilities, and it consists of full-scale HEV systems that can be loaded with either an electric motor dynamometer or a programmable chassis dynamometer. Model-based software development tools and rapid control prototyping hardware are used to control the test bench hardware and to develop and execute control software. The verification environment can also be used e.g. to measure the efficiency of electric traction motors, power electronic converters, energy storages, and hydraulic pumps.

Efficiency of Direct Driven Hydraulic Drive for Non-Road Mobile Working Machines

As answer for tendencies for compact and powerful solution for electro-hydraulic systems, this paper investigates directly driven hydraulic setup for non-road mobile machinery (NRMM) application. The control of the system is implemented directly with a servo motor drive without conventional hydraulic control valves, which allows accurate control and regeneration. Speed of the double-acting cylinder is determined by in-coming oil flow from the pump, out-coming flow to the hydraulic motor and angular speed of the electric motor. The paper provides a detailed analysis of the system and an evaluation of setup usage for NRMM application. Finally, possible improvements of the suggested system are discussed.

Optimal proportion of studded tyres in traffic flow to prevent polishing of an icy road

Studded tyres can significantly wear the road surface and increase particle emissions from the road surface, which has a negative impact on air quality in urban areas. However, road wear might have a positive aspect by roughening the road surface and thus preventing polishing. As a consequence, other vehicles than the ones using studded tyres might also benefit from the usage of studded tyres. The impact of the proportion of studded tyres in the traffic flow on the tyre-ice friction coefficient was studied with a fleet of real cars in a closed environment under strict procedural control. The results show that a proportion of 25-50% studded tyres in the traffic flow is enough to prevent ice from developing in a manner that is critically slippery for non-studded winter tyres. It was also observed that the visual appearance of the ice surface does not indicate if the ice has become more slippery or not.

POSITION CONTROL OF DIRECT DRIVEN HYDRAULIC DRIVE

This paper investigates directly driven hydraulic setup for non-road mobile machinery (NRMM) application. The purpose of this research is to utilize the excellent control capabilities of modern electric drives in electro-hydraulic systems, create direct drive position control for the hydraulic cylinder and verify the results by measurements. The control is implemented directly with a motor drive without conventional control valves. Speed and position of the double-acting cylinder is determined by in-coming oil flow from the pump, out-coming flow of hydraulic motor and angular speed of the electric motor with a single feedback from motor rotor encoder. Empirical results proved that the control suits NRMM application. The achieved maximum final position error of 3.1 % of the position control for tested cycle is fulfilling required accuracy.Copyright

DIRECT-DRIVEN HYDRAULIC DRIVE WITHOUT CONVENTIONAL OIL TANK

The direct-driven hydraulic drive (DDH) combines the advantages of compact high power of the hydraulic system and flexible control of the electric motor. This paper concentrates on modelling of the direct-driven hydraulic setup and investigating control challenges. In the DDH setup, the speed and position control of a double-acting cylinder is implemented directly with a Synchronous Torque Motor drive in a close-loop system without conventional valve-control. In addition to this, hydraulic accumulator is employed as a replacement of the conventional oil tank. To achieve excellent control capabilities, a fuzzy controller is designed to control the rotation speed of the motor drive. The system is investigated by means of simulations. As a result, designed controller benefits the hydraulic system.