Hybrid Propulsion Load Shedding Control to Prevent Generator Overspeed
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In aircraft hybrid engine systems, sudden loss of electrical power from a generator can lead to rapid propagation of faults, damage to propulsion systems, and potential overspeed conditions due to abrupt load changes, which can shorten the service life or cause immediate damage.
Innovation Solution
A series hybrid propulsion system with a gas turbine engine, electrical generator, and electrically-driven propulsors, featuring a voltage regulator that applies an emergency load or variable resistive load to manage power distribution and prevent overspeed conditions by monitoring voltage and current, using a shunt circuit and energy storage to stabilize the system.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the generator is disconnected from the power grid due to a fault, then the electrical power distribution is interrupted, but the gas turbine engine experiences abrupt load reduction leading to overspeed conditions that can cause immediate damage
Solution Approach 1:
An emergency load device is introduced as an intermediary component between the generator and the power grid. This device acts as a mediator that absorbs excess electrical power when the generator is disconnected, preventing the harmful overspeed condition while maintaining system reliability. The emergency load serves as a buffer that protects the gas turbine engine from abrupt load changes.
Solution Approach 2:
The system applies preliminary anti-action by pre-positioning the emergency load device ready to activate immediately upon detection of generator disconnection. The control system monitors the connection status and preemptively prepares the emergency load to counteract the harmful overspeed condition before it can cause damage, rather than responding after the damage occurs.
2Stability of the object's composition
If an abrupt reduction in load on the electrical grid occurs, then the generator may experience overspeed conditions, but maintaining constant load can lead to overvoltage conditions
Solution Approach 1:
The emergency load device employs dynamic resistance control to adapt to changing system conditions. The resistance value is not fixed but is dynamically adjusted based on real-time monitoring of voltage and current levels. This dynamic adjustment allows the system to maintain stability while preventing both overspeed and overvoltage conditions, as the load characteristics change in response to system needs.
Solution Approach 2:
The system changes the electrical parameters of the emergency load device, specifically the resistance value, to optimize performance under different operating conditions. By varying the resistance parameter, the system can control the amount of power absorbed and prevent harmful overvoltage conditions while maintaining grid stability during transient events.
3Reliability
If a fault in the generator causes near instantaneous loss of electrical power, then the propulsion system may experience rapid fault propagation, but delaying detection can significantly damage the propulsion system
Solution Approach 1:
The control system implements continuous feedback monitoring of the connection status between the generator and the power grid. Sensors detect changes in electrical parameters such as current flow and voltage levels, providing real-time feedback to the control logic. This feedback mechanism enables immediate detection of generator faults and triggers the emergency load activation without any significant time delay, preventing rapid fault propagation.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The solution effectively mitigates the risk of propulsion system damage by stabilizing the load on the generator, preventing overspeed conditions, and allowing for safe operation during faults by applying emergency or variable resistive loads, thus extending the service life and ensuring immediate response to power disruptions.
Implementation Method 1
the one or more actions includes applying an emergency load to the generator... the emergency load is applied via a shunt circuit at the voltage regulator... the one or more actions includes applying a variable resistive load to the generator
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A series hybrid propulsion system (10) of an aircraft includes a gas turbine engine (12), an electrical generator (14) operably connected to the gas turbine engine (12) configured to generate electrical power from operation of the gas turbine engine (12), and one or more electrically-driven propulsors configured to provide propulsion for the aircraft, and an electrical power grid (18) configured to distribute electrical power generated at least at the electrical generator (14) to the one or more electrically-driven propulsors. A voltage regulator (20) is positioned downstream of the electrical generator (14) and is configured to take one or more actions to compensate for a loss of load on the generator (14).