Overview
More and more automatic guided vehicles (AGVs) are under consideration as an analysis during the last ten years has shown their effectiveness and cost advantages. At the time of this project only a few ports were equipped with AGVs; most still work with a manual-driven operation.
Such systems are expensive and the pollution aspects with diesel-driven vehicles are high, increasing the energy cost further for operators. Since the signing of the Kyoto Protocol, these diesel engines operating around the clock in harbours that are mostly located in the centre of cities are seen in a bad light due to their polluting features.
The project ISTU considered an alternative technology for such AGVs to overcome some of these major problems within a future generation. ISTU concentrated on the design and specification of a two-container wagon for terminal applications based on a speed of up to 50 km/h with a diesel-electric power supply unit to provide an autonomous integrated electrical propulsion system. The chosen technology can be extended to all major future eco-efficient systems.
The objective was the design, marketing and validation of a container platform, satisfying a practical driving cycle of two-container wagons within terminal applications including their requested security and application aspects.
A major objective was to integrate all the main propulsion components such as motor, power converter, cooling and embedded controllers in one drive. With this propulsion rated at 30 kVA, it was expected the creation of the basic drive component for the container platform with improved characteristics of a reduced cost (by 30%), an efficiency increase of 2% and a system availability of up to 98%, validated by a laboratory set-up.
As a technical goal, the ISTU vehicle was designed for terminal application based on a standard speed of 12 km/h and a maximum speed of up to 50 km/h. The ISTU project optimises and designs the complete vehicle system (i.e. all electro-mechanical components, including a diesel-electric power supply unit to provide an autonomous integrated electrical propulsion system).
The full vehicle integration was part of the project while the engineering work concentrates on the documentation and the specification of all needed components, including the power supply in the form of a cost effective diesel/generation set. The product was evaluated as per its cost targets where strong objectives for market acceptance have been set.
The market approach and the application is a final objective of the project, including security aspects for such systems in their environment and the dissemination in the market of the chosen technology.
The project analysed the needs and application scenarios in harbours with related logistic centres.
Using basic assumptions, the targets for the drive requirements were set and accordingly the engineering process was started. To avoid critical interference from the different involved partners and their tasks, the drive were coupled with the wheels of the platform via a cardan shaft although not a standard in today's rail technology.
Via this approach it was possible to proceed to simultaneous engineering while the cost targets were reached. The design of the vehicle and the propulsion was done individually.
A first prototype of the Integrated Propulsion Motor Unit called 'IPMOT' confirmed the technical features and revealed improvement possibilities with regard to the overloading characteristics of such a motor. These features were integrated in a redesigned and completed product.
In parallel, the full vehicle was designed with a proper diesel-electric power supply unit and all components integrated in the vehicle structure. As an extension of this technology, a road driven vehicle was additionally analysed.
Funding
Results
To cope with the objectives a simple switched reluctance 30 kW motor as base propulsion component was chosen This motor and its components to be integrated were dimensioned and the layout done for all the requested components of this integration process. Furthermore a brake system has been added on the shaft of the motor.
Within a redesign it has increased the overload capabilities considerably as to allow the integrated motor to be the main component within future hybrid drives. Additionally this drive has been analysed for road operation which is an alternative market request. The engineering for a rail vehicle is actually validated in a test belt although the simulated results are demonstrating the targeted values already.
Dissemination was done through several conferences and in the World Cargo News. Technology was actually presented to different ports and will be demonstrated on a fair next. A follow up intends to intensify the work on a suitable logistic control to come to an unmanned automatic piloted transport system for eco-efficient electrical power supply system.
Technical Implications
A first prototype of the integrated drive called IPMOT confirmed the technical features and revealed some improvement possibilities with regard to the overloading characteristics of such motor. In a further redesigned and completed product, we integrated these features by smaller changes in the winding layout. Parallel the full vehicle was designed, a proper diesel-electric power supply unit chosen and all components integrated in the vehicle structure.
The vehicle is called the 'Integrated standard transportation unit' (ISTU) and is designed as an alternative to conventional locomotive-pulled freight for rail applications on rail, for drayage between cargo distribution centres and in port container yards as an AGV. A major part of the research project was to design drive components suited for hybrid application which is expected to be more cost and eco-efficient, fuel efficient and reliable than what is available today on the market. ITAPS has developed an integrated motor concept (IPMOT) that is similar to the once used in the latest hybrid cars but with high overloading capabilities. With this technology it is expected to reduce the pollution in modern harbours. With our future hybrid concept and this motor, AGVs will overcome the inertia of a heavy load even with nearly half the power of today diesel engines. The new electric propulsion concept has been developed based on switched reluctance motor technology - an AC motor with no windings or permanent magnets on the rotor which gives a high reliability to the product. With a 80-100 kW engine a low-speed rail application, where the load on a two-axle ISTU is limited by the 22.5 t axle load, can be realised. Within partnerships between ITAPS and companies from Poland and the Czech Republic the ISTUs and AGVs will be produced.
Readiness
Extension to industrial dense areas where such systems are expected to reduce road traffic, pollution and noise is possible. ISTU is an official Trade Mark.