Basic Requirements Of Control Systems

‌Basic requirements of control systems mainly include stability, steady-state accuracy and dynamic response speed. ‌‌

‌Stability‌: Stability is the most basic requirement for control systems. System stability means that when disturbed, although the controlled quantity will deviate from the original equilibrium state, the system can return to the original equilibrium state after the disturbance is eliminated. Stability requires that the system can still work normally when the internal parameters change slightly or the initial conditions change.

‌Steady-state accuracy‌: The steady-state accuracy of the system is usually expressed by the steady-state error. The smaller the steady-state error, the higher the accuracy of the system output following the reference input. Even if the system is disturbed, its output will gradually recover to the original equilibrium state. After reaching the steady state, the difference between the system output and the expected output is the steady-state error.

‌Dynamic response speed‌: The dynamic response speed requires the system to respond quickly when disturbed or the input signal changes. This includes indicators such as the system's rise time, overshoot and adjustment time. Fast response means that the system can reach or approach its target state in a short time.

In addition, the design of the control system also needs to consider other factors, such as the nonlinearity and time-varying nature of the system. Nonlinear systems do not have homogeneity and superposition principles, and their output response and stability are related to the initial state. Time-varying systems refer to system parameters that change over time, which affects the stability and performance of the system.