Predictive Radiant Heating Thermostat for Overshoot Control

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional heating and cooling systems, particularly radiant heating systems, suffer from overshooting and undershooting due to thermal inertia, leading to inefficient energy use and discomfort, and existing thermostats face challenges in installation and user interface, especially in homes without a 'C' wire for power connection.

Innovation Solution

A thermostat with a processing system that uses predictive controls, including a parameterized model based on historical data to determine optimal control strategies for radiant heating systems, allowing for efficient temperature management without the need for a 'C' wire or household line current, featuring a user-friendly interface and wireless communication capabilities.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Loss of energy

If conventional heating control systems are used, then the system is simple to implement, but the system suffers from overshooting and undershooting due to thermal inertia, leading to energy inefficiency and discomfort

Engineering Contradiction:
Improveenergy efficiencyVSAvoidcontrol system complexity
Core Design Contradiction:
Loss of energyVSDevice complexity

Solution Approach 1:

The control system performs preliminary actions by predicting future temperature trends based on historical data and thermal models before overshooting or undershooting occurs. The system proactively adjusts heating operations in advance to prevent temperature deviations, rather than reactively responding after the problem occurs.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The system implements continuous feedback loops that monitor actual temperature measurements against predicted temperature trajectories. This feedback mechanism allows the control system to detect deviations early and adjust heating operations to maintain optimal temperature, preventing energy waste from overshooting and undershooting.

Inventive Principle:
Principle #23Feedback

2Ease of manufacture

If electronic thermostats are used without a C wire, then power stealing methods can be employed to avoid additional wiring, but the thermostat must rely on power stealing which limits its functionality and reliability

Engineering Contradiction:
Improveinstallation simplicityVSAvoidpower supply reliability
Core Design Contradiction:
Ease of manufactureVSReliability

Solution Approach 1:

The thermostat performs self-service by automatically detecting the presence of a C wire through impedance measurement and other electrical characteristics analysis. The system autonomously determines its power supply configuration and adapts its operation accordingly, eliminating the need for manual installation configuration or user intervention.

Inventive Principle:
Principle #25Self-service

Solution Approach 2:

The system changes its operational parameters based on the detected power supply configuration. When a C wire is detected, the thermostat switches to a more reliable power mode with enhanced functionality. When no C wire is present, it adapts to power-stealing mode with adjusted operational characteristics, optimizing performance for each scenario.

Inventive Principle:
Principle #35Parameter changes

3Ease of operation

If radiant heating systems operate with conventional control, then the system is easy to control, but thermal inertia causes the ambient temperature to continue rising above setpoint after heating discontinuation (overshooting) and falling below setpoint after heating resumption (undershooting)

Engineering Contradiction:
Improvecontrol simplicityVSAvoidtemperature control precision
Core Design Contradiction:
Ease of operationVSManufacturing precision

Solution Approach 1:

The control system takes preliminary action by predicting the thermal response of the radiant heating system before making control decisions. Using historical temperature data and thermal models, the system anticipates how long heating effects will persist after shutdown and how long it will take for temperature to drop to setpoint after restart, allowing it to pre-adjust control timing to prevent overshooting and undershooting.

Inventive Principle:
Principle #10Preliminary action

Data Source

PatentUS10012407B2Heating controls and methods for an environmental control system
Publication Date: 2018.07.03 GOOGLE LLC
  • US10012407B2 patent drawing
  • US10012407B2 patent drawing
  • US10012407B2 patent drawing

AI summary

Embodiments of the invention describe thermostats that use model predictive controls and related methods. A method of controlling a thermostat using a model predictive control may involve determining a parameterized model. The parameterized model may be used to predicted ambient temperature values for an enclosure. A set of radiant heating system control strategies may be selected for evaluation to determine an optimal control strategy from the set of control strategies. To determine the optimal control strategy, a predictive algorithm may be executed, in which each control strategy is applied to the parameterized model to predict an ambient temperature trajectory and each ambient temperature trajectory is processed in view of a predetermined assessment function. Processing the ambient temperature trajectory in this manner may involve minimizing a cost value associated with the ambient temperature trajectory. The radiant heating system may subsequently be controlled according to the selected optimal control strategy.