The general motivation for this project, starting with Phase I, has been the need for systematic control co-design of power provision to the emerging vehicle architectures. Instead of designing specific hardware for the best static ratings and functionalities of the key equipment, dynamic inter-dependencies and functionalities must be modeled and controlled. This nonlinear fast control has become possible by progress in power electronics and materials. However, missing is the control logic for integrating these highly diverse technologies into a system which must meet difficult multiple performance objectives. This project is intended to fill this void. The unique contributions of this project are control and protection logic for providing power to vehicles operating over broad ranges of conditions. These include challenging missions as well as faults.
In this project we view a vehicle as a composition of dynamically-controlled subsystems whose interactions depend on how sensing, control and protection are designed and integrated. The overall approach is the one of ``co-design” by which the candidate architecture is selected for its functionalities, control is designed and the hardware-control-protection integrated system is re-assessed for its performance. This approach is one of the major new R&D&D pursued for changing terrestrial sources and the emerging power systems, including stand-alone microgrids. The problem of power train design for vehicle architectures is even harder because of the needs to reduce their weight and thermal effects, all else being equal. This requires control co-design selection of machines (DC, permanent magnet (PM), synchronous machines SM), doubly fed induction machines (DFIM)) and their power electronically-controlled conversion logic so that the integrated system meets previously unmet functionalities. This is achievable through cooperative control and protection of vehicle resources, loads and their interfaces.
The energy based control framework developed here directly addresses the need to integrate individual aircraft energy system components into electric power systems that operate in ways to ensure fault-tolerance, stability and efficiency. It introduces a multi-layered interactive approach so the desired power is provided in transiently stable ways in response to varying aircraft situations. The approach can be extended to controlling electric power systems for single vehicle and future multi-vehicle manned deep-space missions.
The non-NASA commercial applications primarily concern the operation of terrestrial electric power systems such as utility systems, “smart” grids and micro-grids. The proposed framework enables a significantly new approach to the modeling and control of future electric power systems which require the integration of diverse energy storage and intermittent resources.