Distributed Control Modules With Built-In Fault-Preserving Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Distributed control systems face challenges in maintaining controllability of turbomachines when a distributed control module fails, leading to potential loss of control, reduced efficiency, or damage to the turbomachine, especially due to communication or sensor faults.
Innovation Solution
Incorporating a built-in test module within the distributed control module to determine fault states and switch to augmented control regimes, such as augmented closed-loop or open-loop control, to preserve control of controllable components, even in the presence of communication or sensor faults, thereby minimizing the impact of failures.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If distributed control modules are used to localize control commands, then system reliability is improved by isolating failures to individual modules, but control may be lost when a module fails due to communication or sensor faults
Solution Approach 1:
The control module performs self-diagnostics and detects fault states before they lead to complete control loss. By proactively identifying communication faults, sensor faults, or actuator faults, the system can switch to alternative control modes in advance, maintaining control continuity and preventing total failure of the controllable component.
Solution Approach 2:
The control module dynamically switches between different control modes (normal mode, augmented control mode, safe mode) based on the detected fault state. This dynamic adaptation allows the system to maintain control of the controllable component under varying fault conditions, transitioning from closed-loop control to open-loop control or other alternative modes as needed.
2Difficulty of detecting and measuring
If built-in test modules are added to detect fault states, then fault detection capability is improved, but device complexity increases
Solution Approach 1:
The built-in test module is integrated within the distributed control module itself, combining diagnostic functions with control functions in a single unit. This merging eliminates the need for separate external diagnostic systems, reducing overall system complexity while maintaining comprehensive fault detection capabilities for communication faults, sensor faults, and actuator faults.
Solution Approach 2:
The control module is designed with multi-functionality, serving both as a control unit and a diagnostic unit. The same hardware and software resources are used for both normal control operations and self-diagnostics, allowing the module to detect multiple types of faults (communication, sensor, actuator) without requiring dedicated separate systems for each function.
3Reliability
If control modes are switched based on fault states, then control continuity is improved, but control logic complexity increases
Solution Approach 1:
Alternative control modes and their associated control logic are pre-configured within the control module before faults occur. When a fault state is detected, the module simply switches to the pre-prepared alternative mode rather than computing a new control strategy in real-time. This approach maintains control continuity while minimizing the computational complexity of fault response logic.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A distributed control system (100) may include a main processing unit (102), a distributed control module (104), and a controllable component (112). The distributed control module (104) may be configured to determine a fault state (400) associated with a control loop (600) using a built-in test module (300). The built-in test module (300) may be incorporated into the distributed control module (104). The fault state (400) may include no faults (508), a communication fault (510), a sensor operation fault (512), or a controllable component fault (526). The distributed control module (104) may be configured to transmit a closed-loop control command (602) from the distributed control module (104) to a controllable component (112) when the fault state (400) comprises no faults (508), or transmit an augmented control command (604) from the distributed control module (104) to the controllable component (112) when the fault state (400) comprises a communication fault (510) or a sensor operation fault (512), or transmit a disconnect control command (634) from the distributed control module (104) to the controllable component (112) when the fault state (400) comprises a controllable component fault (526).