====== What is PID control ====== \\ \\ \\ **PID Control** \\ {{ :pid_block_diagram.jpg?direct&400 |}} \\ {{ :pid_waveform.png?direct&400 |}} \\ - A feedback-based control loop that compares the actual value with the target value. \\ - Combining the Proportional, Integral, and Derivative components, PID control reduces the system's error to make the output reach the set point and maintain that sate effectively. \\ - u(t) = {Kp x e(t)} + {Ki x ∫e(𝜏)d𝜏} + {Kd x de(t)/dt} \\ - u(t): control signal \\ - e(t) = Set point - process variable \\ - Kp: Proportional gain, Ki: Integral gain, Kd: Derivative gain \\ \\ **(i) Proportional** \\ {{ :p_control.jpg?direct&400 |}} \\ - The error is corrected in proportion to its current magnitude. \\ - P control output = Kp x Error \\ - If Kp is too large, overshoot and oscillation may occur. \\ \\ **(ii) Integral** \\ {{ :i_control.jpg?direct&400 |}} \\ - The error is corrected by considering the accumulated error over time. \\ - It helps eliminate small, long-standing errors, known as steady-state error. \\ - I control output = Ki x ∫(Error)dt \\ - If Ki is too large, the system may respond slowly or become unstable. \\ \\ **(iii) Derivative** \\ {{ :d_control.jpg?direct&400 |}} \\ - The derivative term predicts future error by analyzing the rate of change of the error and suppresses excessive responses. \\ - D control output = Kd x d(Error)/dt \\ - It reduces oscillation and helps stabilize the system smoothly.