PI, PD and PID combinations
Цель: Изучить тему «PI, PD and PID combinations» и закрепить её практическими заданиями и самопроверкой.
2 акад. часа чтение и разбор теории, решение задач, работа со схемой или виртуальным стендом и проверка понимания.
Основной материал
PI combines fast proportional reaction with offset removal. PD combines proportional with predictive damping but leaves offset in self-regulating process. PID combines all three.
Tuning trade-off
Fast response, low overshoot, disturbance rejection and robustness conflict. Aggressive tuning may give quick setpoint response but poor noise sensitivity and valve wear. Industrial tuning aims acceptable performance across disturbances, not perfect graph in one test.
Practical comparison
Level loops on integrating processes often use PI but tuning differs from self-regulating temperature. Flow loops often use PI with fast integral. Temperature may use PID/PI depending dynamics.
Практическая работа
For pressure, level, temperature propose initial controller structure P/PI/PID and justify. Not final tuning - choose based on dynamics/noise.
Самопроверка
• Why PI popular?
• What does PD lack?
• What trade-offs in tuning?
• Why one structure not universal?
• How valve wear relates aggressive control?
Что нужно запомнить
- PI combines fast proportional reaction with offset removal.
- PD combines proportional with predictive damping but leaves offset in self-regulating process.
- Fast response, low overshoot, disturbance rejection and robustness conflict.
- Aggressive tuning may give quick setpoint response but poor noise sensitivity and valve wear.
- Industrial tuning aims acceptable performance across disturbances, not perfect graph in one test.