Updates over time have allowed DTC to reach beyond demanding, high-dynamic applications for which it was created. Software improvements and the commonality of high-power microprocessors make DTC drives economically justified for wider implementation. Ability to respond rapidly to changes in process variables, such as pressure, tension, or position using exceptional speed and torque control dynamics makes DTC attractive to more industries.
Moreover, AC drives offer dramatic energy savings potential for large numbers of variable-speed pump/fan applications. Because pump speed versus power has a cubic relationship, a process sequence that allows the pump to run at 50% speed would use only 1/8 of full power.
Direct torque control has shown a continuum of hardware and software developments over its near 30-year lifespan. Based on firm theoretical foundations and DSP technology, DTC has overcome limitations of the early processors. Powerful processors now rapidly execute complex control algorithms, update motor model parameters, and switch the drive’s transistors for optimal performance.
ABB’s respected drive engineering heritage and substantial resources have gone into developing direct torque control. Today, DTC remains a living technology. It has grown into a brand larger than “torque control” by incorporating intelligent user interfaces, drive diagnostic features, and system-level software.
Looking ahead, ABB intends to follow the same path with its enduring DTC technology. Customers of ABB drives can be confident that the benefits of direct torque control in which they invest today will continue for the long term.