PLC PID Constant Pressure Water Supply Design (42 chars)

Design of PLC-Based PID Constant Pressure Water Supply System

Student: XXX Supervisor: XXX College: XXX Date: 2023.X

• Design Goal: Constant Pressure Water Supply
• Core Concept: PLC Executes PID Algorithm
• Control VFD to Regulate Pump Speed
• Maintain Stable Pipeline Pressure

• Traditional supply: Significant pressure fluctuations
• Traditional supply: High energy consumption
• Constant pressure needs: Stable water supply
• Constant pressure needs: Energy savings
• Constant pressure needs: Intelligent control

• Design PLC-based PID Constant Pressure Water Supply System
• Improve Water Supply System Efficiency
• Significantly Reduce Pump Energy Consumption
• Promote Industrial Automation Applications

PLC Solution Advantages Stable, reliable; strong anti-interference; modular design enables easy expansion and maintenance. Ideal for industrial constant pressure water systems; ensures long-term efficiency, low failure rate.

Microcontroller Solution Features Low cost, compact; poor scalability, weak anti-interference. Unsuitable for complex control; high programming/maintenance difficulty, insufficient industrial reliability.

Mature VFD + PID Integration International research integrates VFDs with PID controllers into standardized solutions. Enables precise motor speed control and closed-loop pressure regulation, widely used in industrial automation for enhanced stability and response.

Europe/US Water System Applications VFD-PID constant pressure solutions in Europe/US water systems achieve 30%+ energy savings. Reduces consumption, boosts reliability, minimizes wear—proving high maturity.

• CTH200 series PLC, inverter, water pump form system
• Sensors provide real-time pressure feedback
• PLC executes PID algorithm calculations
• Inverter regulates pump speed for constant pressure

Control, Detection & Alarm Components Control: CTH200 PLC handles PID algorithm, logic control. Detection: Pressure sensors monitor network pressure; level sensors track tank levels. Alarm: Over/low pressure, level limits ensure safe, stable operation.

Water Pump & Pipeline Schematic Features main/auxiliary pumps, tank, pipeline network. Supply flow: Tank storage → Pump boost → Pipeline delivery → End user; variable frequency constant pressure closed-loop control.

• PID Principles: Proportional (P), Integral (I), Derivative (D) Control
• P Control: Output proportional to error magnitude
• I Control: Integrates error to eliminate steady-state offset
• D Control: Predicts changes to suppress overshoot oscillation
• PLC Implementation: Ladder logic for real-time output
• Drives VFD: Regulates pump speed for constant pressure

• Real-time tank level monitoring with upper/lower thresholds.
• Upper limit: Close inlet valve and trigger alarm.
• Lower limit: Start pump and execute alarm logic.
• Alarm reset: Automatic when level normalizes.

• Sensor Drift → Recalibrate Sensor.
• Communication Failure → Check Cables & Interfaces.
• PID Oscillation → Optimize Proportional/Integral Parameters.
• Liquid Level Alarm Failure → Verify Switch Status.
• Water Pump Not Starting → Check Power Control Signal.

**Achievements

• Successfully built stable constant pressure water supply system
• Precise PID control enables energy efficiency

Improvement Directions

• Integrate wireless monitoring module
• Introduce AI algorithms for parameter optimization

Closing Remarks: Project successfully concluded, prospects unlimited!**

Welcome Questions and In-Depth Discussion

> Heartfelt thanks to my advisor for guidance and advice, classmates for help and discussions, and family for support and encouragement. This achievement is due to your contributions. 🙏

— Li Ming, Undergraduate, School of Automation