Ghulam Mustafa

Research Interests

My research is primarily focused on Control Systems. A few areas of current interest are:

  • Sampled-data control

  • Robust control

  • Cyber-physical systems

  • Application of control to power systems

Sampled-Data Systems

Most modern control systems manufactured today are implemented using digital computers and are referred to as computer-controlled systems or sampled- data systems. Using computers to implement controllers offer many advantages over analog implementation, such as, the controller can be easily re-programmed, controller is a software program so changes in hardware components do not affect it and delay can be handled easily.

Modern Sampled Data System 

Recent years have seen a rapid development in communication, computation and sensing technologies. This has opened up the possibility to design very large and complex control systems by integrating computation, control and communication. Figure shows a typical configuration of a modern sampled-data control system. A distinctive feature of this configuration is that all information between the controller and the plant is exchanged through a shared communication network.

Closing the control loop through a communication network has the advantages of reduced wiring cost and ease of maintenance and debugging; however, it makes the analysis and design of control system harder. It may not be possible to guarantee constant sampling periods and synchronized operation of the sampling and hold devices. For such systems, if a controller is designed with the assumption of constant sampling period, this could degrade the system performance and may even lead to instability of the closed-loop system. This motivates the development of sampled-data theory where the assumptions of constant sampling period and synchronized operation of sampler and hold are relaxed.

Our group has made some theoretical contributions in this area. Please see publications section for details.

Power Systems

The traditional power grid has unidirectional flow of information (power). A recent trend is to modernize the grid by integration of control, communication and IT infrastructure. This modern grid termed “Smart Grid” will facilitate in reducing the environmental impact and transparency of operation of the power system. However, integration of these control, communication and computation resources brings new challenges for the designer. Moreover, increase in loading put extra stress on the transmission system because transmission capacity has not increased proportionally. The transmission system is required to operate near the maximum capacity. Operators need more reliable information to operate the system.

Our research is focused on developing analysis and design tools for the safe, reliable and efficient operation of the smart grid. Please see publications section for contributions of our group in this area.