TECHNOLOGIES

MACCON is specialized in many areas of electric motor and drive technology. Here are some of the highlights:

    SWM Hi-Rel Motorcontroller

    REDUNDANT SYSTEMS

    In many critical applications such as MIL and Aerospace reliability is essential. Motion systems may not fail, correctly expressed - they must offer excellent availability.

    In the field of aircraft actuation for example the target is to achieve a level of MTBF, which is comparable with that of hydraulic systems. 

    To achieve high availability we combine two techniques. We design our sub-systems to high quality levels and to derating standards but also provide redundancy at motion system level.

    This redundancy may be either:

    • Dual – a single failure may result in reduced performance but system operation must still be possible (this might be the requirement for an automobile or life-support system) – OR
    • Triple – the failure of one channel causes no loss in performance; a second failure may result in reduced performance but system operation must still be possible (this is typically the requirement for aircraft)

    In both cases the failure must be recognised and reported to the host control system, which itself may be redundant!

    Motors & Sensors

    At the motor level we have developed redundancy design techniques both for permanent-magnet and for switched reluctance machines.
    In some cases, depending on the mechanical solution it can make sense to duplicate the motor completely.

    At sensor level both approaches may apply – full duplication (or triplication) or use of multiple reading-heads using the same sensor disc.

    Mechanics

    In order to achieve high reliability high design standards must apply. These include the optimum choice of materials as well as stress analysis to allow for the worst-case load, force and acceleration conditions. At the same time every effort must be made to minimise the mass of the mechanical sub-system. 

    In mechanical designs redundancy techniques are also feasible. Both gearboxes and linear screw systems can be made to include two parallel torque or force transmission paths; if one fails, the other takes over the full load.

    Power electronics

    In addition to high MTBF and derating design techniques we also apply redundancy principles in our power electronics design. The latter approach makes high demands on miniaturisation, interconnections and packaging; the power stages otherwise become large and bulky, which in most applications is not acceptable.

    Software & Control

    The demands on our real-time software are very high, particularly with regard to documentation and verification.
    Often the control hardware is redundant, full duplication or triplication applies.
    Such redundant control sub-systems are managed by arbitration logic – the two working systems override and take over control from the system, which has failed or which is producing a contradictory command.