Networked Water Heater Control for Balanced Load and Wear
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional cascade water heater systems face issues with uneven usage distribution among water heaters, leading to disparate wear and tear, inefficient energy conservation, and the need for a more accurate method to estimate remaining life, as well as the risk of single-point failures and excessive cycling due to fixed control schemes.
Innovation Solution
A masterless control method where each water heater controller communicates via a communication bus, broadcasting usage planning data and adjusting heating loads based on efficiency and usage history to distribute demand seamlessly across the network, eliminating the need for a master controller and allowing for dynamic addition or removal of units without disrupting service.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If a single water heater is used, then the system is simple, but it provides a single point of failure and cannot meet varying large demands
Solution Approach 1:
The system divides a single water heater into multiple independent water heater units (first water heater, second water heater, third water heater, etc.), each capable of operating autonomously. This segmentation eliminates the single point of failure by distributing the heating function across multiple units, while each unit maintains its own controller and communication capability.
2Reliability
If multiple water heaters are cascaded, then demand coverage and reliability improve, but usage distribution becomes uneven causing disparate wear
Solution Approach 1:
The system dynamically adjusts the operational status of each water heater unit based on real-time demand and usage history. Controllers communicate usage data and receive commands to modulate or shut off specific units, creating a dynamic load distribution that adapts to changing conditions rather than following a fixed cascade pattern.
Solution Approach 2:
Each water heater controller monitors its own usage and communicates this information to other controllers in the network. The system uses this feedback to make informed decisions about which units should be active, ensuring that wear is distributed more evenly across all units based on their current state and historical usage patterns.
3Ease of operation
If a master controller is used, then coordination is centralized, but the system becomes vulnerable to single-point control failures
Solution Approach 1:
The invention extracts the master controller function from the system, eliminating the centralized control point. Each water heater unit is equipped with its own controller that can independently make decisions about operation, modulation, and shutdown based on communications with other units, removing the single point of control failure.
Solution Approach 2:
Each water heater unit is empowered to make its own operational decisions through its controller. The units self-coordinate by exchanging information about demand, usage, and status, allowing each unit to autonomously determine when to operate, modulate, or shut off without requiring instructions from a central authority.
4Ease of manufacture
If fixed control schemes are used, then implementation is simple, but excessive cycling occurs when demand falls within dead bands
Solution Approach 1:
The control scheme transitions from a fixed, predetermined sequence to a dynamic system that adjusts unit operation based on real-time demand conditions. When demand falls within what would traditionally be a dead band, the system dynamically determines which units should operate and at what modulation levels, preventing excessive cycling through coordinated control.
Solution Approach 2:
The system changes the operational parameters (modulation levels, on/off states) of individual water heater units based on current demand conditions rather than following a fixed sequence. This allows the system to adapt to varying demand patterns and avoid the excessive cycling that occurs with rigid fixed control schemes.
Data Source
AI summary
Disclosed is a masterless control system for controlling a plurality of fluidly and operably connected water heaters to meet a hot water demand such that overall efficiency is maximized and usage disparity between water heaters is minimized. There is further disclosed a method for detecting a small system demand in said network by adjusting the setting of each flow limiting valve of each water heater. There is still further disclosed a method for enabling seamless addition or removal of a heater in service and heating load distribution to water heaters.