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With linear actuated brakes the actuation force (or torque) rises linearly from 0 to the full actuation force at full braking. This means that the actuation must be designed for the rare case of full-braking. The parts must be designed for this peak load (e.g. motor, gear) and the transmission ratio is determined by the full-braking actuation torque, which causes the highest transmission ratio and hence determines slow actuation dynamic. Ideally the actuation should make the fastest travel at low normal force and turn to slow movement and high force at the highest pad force. Mathematically the torque transmission ratio should optimally be an exact representation of the actuation characteristics (actuation torque over actuation movement), creating the highest torque-transmission ratio at highest force and the fastest movement at low pad force.

The VE-brake is an electromechanical disc brake with very low actuation force, actuated by a small electro motor. It was originally conceived as a vehicle brake but is equally applicable to wind turbines and other equipment. It has been highly successful in extreme dynamometer tests and is now being installed in test vehicles. As a foot-brake the VE-brake releases automatically at power-off and can be actuated to a parking position, which stays at power-off. The auto-release function can be inverted so that it brakes automatically at power-off as an emergency brake for wind turbines and rolling stock. A considerable amount of electricity is required to keep conventional windmill-brakes released. In light wind, the VE brake enhances yield by permitting the turbine a lower start-up speed, and in gusty or higher wind speeds, the graduated activation enables the turbine to continue functioning in demand-braked mode, rather than switching to emergency shut-down mode.

Conventional brakes commence with given brake torque distribution and abruptly change to wheel individual torque corrections when ABS-ESP intervenes. This leads to less than optimal braking, firstly around the transition from “given distribution” to individual ABS-ESP control and secondly when ABS-ESP switches from “locked” to “rotating”. Neither of these states offers the optimal deceleration. The VE mechatronic brake (EMB, electro mechanical brake) is designed to apply wheel individual braking with wheel optimized torques that give the best braking and stability from initial input to maximum deceleration, without sudden transition to ABS-ESP. With electric drive motors, a very rapid adjustable part of wheel individual torque can be combined with the individually controllable VE brakes.