New proposed adaptive frequency load shedding scheme for cogeneration plants

Industrial power systems can benefit from load shedding following loss of utility mains. Conventional underfrequency load shedding has been the most common technique applied to save a system from blackouts. This method is based on multiple frequency settings where pre-specified amounts of load are shed when these levels are breached. As the shed and see principle was not immune to blackouts a rate-of-change-of-frequency (ROCOF) technique was developed to enhance its performance. The ROCOF method proved to require an adequate knowledge of the power system operating strategies. The authors demonstrate the dependence of ROCOF on the power system configuration and propose a new adaptive technique which utilises online information of the operating status of the overall system