Q. Explain state-variable techniques?

The matrix formulations associated with state-variable techniques have largely replaced the block-diagram formulations. Computer software for solving a great variety of state-equation formulations is available on most computer systems today. However, in the state-variable for- mulation, much of the physical reality of any system is lost, including the relationships between system response and system parameters.

With the development and widespread use of digital (discrete) control systems and the advent of relatively inexpensive digital computers, time-response methods have become more necessary and available. These may be divided into two broad methodologies:

1. The actual simulation or modeling of the system differential equations by either analog or digital computers.

2. The state-variable formulation of the system state equations and their solution by a digital computer. State-variable methods offer probably the most general approach to system analysis and are useful in the solution of both linear and nonlinear system equations.