Electrical Drive System for Mobile Cranes

Kurzfassung

A blue-chip Austrian company is developing an electrical drive system for mobile cranes (predominantly Permanent Synchronic motors) to achieve a high dynamic dimensional performance for mobile cranes and lifting technologies without the need for sensors. A major advantage of the drive system concept is the possibility to control the exact rotor position of the telescope motor and the position of the crane arm. They are searching for development partners and licensees in the engineering sectors.

Details

General Description:
An Austrian blue-chip company is a specialist manufacturer of crane and lifting technologies and is developing a new drive system process for positioning and energy control without the need for sensors. The INFORM system utilises electric motors (predominantly Permanent Synchronic motors) to achieve a high dynamic dimensional performance.

The basic idea consists of transforming three-phase current into electrical energy and dispersing this energy through a current converter to the individual parts of the crane where the energy is once again transformed into mechanical movement.

A major advantages of INFORM with mobile cranes is the possibility to use a cost-effective selective motor steering. A parallel utilisation of electrical cable and the information leads.

A prototype of this system will be built into a standard mobile crane type:
- Development of the drive system components
- Combustion of the motors and electronics
- Integration into a prototype

Automation of the system movements is accomplished through simple electrification without the use of bus cable, which allows for versatile movement over short distances and represents a significant advantage over energy transmissions utilising heavy hydraulic systems.

Through long electrical cables as required by a crane, a voltage shock wave is able to bring the function of the regulator to a standstill.

The drive tasks demand a highly dynamic motor regulation with a high starting moment. This is possible through the concept of field-oriented regulation (vector regulation) of the three-phase generator. The INFORM system offers sensor-less regulation up to the point of standstill. A major advantage of the drive system concept is the possibility to control the exact rotor position of the telescope motor and the position of the top of the crane arm. Another important aspect is the possibility of retraction when exposed to a strong force as the motor regulation concept recognises the abrupt movement within milliseconds and allows for a dynamic response.

The INFORM process allows for an accurate control of synchronic or asynchronic machines without any of the associated disadvantages that would be associated with compact systems utilising lower-frequency speeds.

Patent Strategy:
Patents are to be registered for the entire crane design, the telescope drive system, the electronic solutions and the current converter. Patent research has been undertaken to ascertain the viability of the proposed patents with positive a response. The potential for the logistics industry is substantial, especially goods transport and logistics.

Present Level of Technology:
Electrical drives dominate stationary cranes where there is space to house the speed generator and the bus cable connections. This is not the case for mobile transport cranes technologies.

Innovative Aspects:
Technical description:
The development of an electrical drive system utilising electrical servo motors systems.

This technology replaces hydraulic systems with the advantages of no loss of hydraulic oil and a clean electrical drive system.

Electrical systems for mobile loading cranes are only of interest when they achieve the same performance level as hydraulic systems with regard to weight requirements. The INFORM system offers the best technical conditions:

- Will reduce the rotor temperature and the electrical motors can accordingly be of small dimensional construction.

- The size of construction can be further reduced by the removal of an external speed generator (revolutions), which is normally essential for the control, and steering of a crane.

Main Advantages:
Economical Advantages:
The new system and technologies offer solutions for transport and logistic centres with respect to a faster turnaround for loaded and unloaded goods, primarily in the rail logistics branch, and will offer diversity and complementarities to the more common systems already available.

The long-term security of the industry will be secured based on the robust, sensor-less and environmentally friendly industrial drives and motors.

A feasibility study has been conducted to ascertain the technical and economical advantages when taking safety considerations into account for crane and lifting technologies.

The INFORM process drive-system concept enables the design and development of compact electrical motors and machines with a substantial weight reduction.

This concept is of particular use for mobile transport interfaces and allows for the possibility to position without the additional rotation transducer. This means that there is no malfunctioning bus cable.