Open-loop vs closed-loop control in Power Electronics - Hands-On Comparison

Understanding Open-loop vs Closed-loop Control

📖 Scenario: You are designing a simple temperature control system for a small room heater. You want to understand how open-loop and closed-loop control methods work in this real-world context.

🎯 Goal: Build a step-by-step conceptual model that shows the difference between open-loop and closed-loop control using simple variables and logic.

📋 What You'll Learn

Create a variable representing the heater power level

Add a target temperature setting variable

Implement open-loop control logic to set heater power without feedback

Implement closed-loop control logic that adjusts heater power based on actual temperature feedback

💡 Why This Matters

🌍 Real World

Understanding open-loop and closed-loop control helps design systems like thermostats, motor speed controllers, and automatic lighting.

💼 Career

Control systems knowledge is essential for engineers working in automation, robotics, power electronics, and HVAC industries.

1

DATA SETUP: Define heater power and actual temperature variables

Create two variables: heater_power set to 50 (representing 50% power) and actual_temperature set to 20 (degrees Celsius).

Power Electronics

# Create variables heater_power and actual_temperature with given values
# Your code here

Need a hint?

Think of heater_power as how much energy the heater uses, and actual_temperature as the current room temperature.

2

CONFIGURATION: Set the target temperature

Add a variable called target_temperature and set it to 22 (degrees Celsius), representing the desired room temperature.

Power Electronics

heater_power = 50
actual_temperature = 20
# Define target_temperature variable
# Your code here

Need a hint?

This is the temperature you want the room to reach.

3

CORE LOGIC: Implement open-loop control logic

Write a comment explaining open-loop control, then set heater_power to 70 without using actual_temperature or feedback.

Power Electronics

heater_power = 50
actual_temperature = 20
target_temperature = 22
# Explain open-loop control and set heater_power to 70
# Your code here

Need a hint?

Open-loop means the heater power is set blindly, without checking if the room is warm enough.

4

COMPLETION: Implement closed-loop control logic

Write a comment explaining closed-loop control, then use an if statement to increase heater_power to 80 if actual_temperature is less than target_temperature, otherwise set it to 30.

Power Electronics

heater_power = 50
actual_temperature = 20
target_temperature = 22
# Open-loop control sets heater power without feedback
heater_power = 70
# Add closed-loop control logic below
# Your code here

Need a hint?

Closed-loop means the heater power changes depending on the room temperature compared to the target.