Control System Design for HVDC system

High voltage direct current (HVDC) systems are used in electrical power systems as a supplement to AC power transmission. Power transfer by means of HVDC must be used in the case of asynchronous AC systems and high voltage cables longer than about 50 Km. The control of DC power through an HVDC link can be achieved through the control of direct current or voltage, which are determined by firing angle control of the valves. Other variables such as reactive power and AC voltage can be controlled by a combination of firing angle control, transformer tap-changer control, and reactive shunt element switching. The complexity of HVDC controls has increased over the years. The reason for this is two fold: 1. Digital signal processors make it possible to incorporate extensive functionality.2. Customers ask for more extensive functionality to assist the AC system.In this project main research objectives are:1. To get fundamental insight into the dynamic properties of an HVDC plant from a control theory perspective.2. To evaluate modern digital simulation tools, like EMTDC and SimPower for HVDC controller design and testing.3. To explore how classical or modern control theory can be used to tune systematically linear and linear parameter varying controllers for performance and robustness over complete range of operations.