SBIR-STTR Award

MSI proposes to develop a reliable control system that will electrically combine multiple 10 to 50kW turbo-alternators to create a stable 100 to 500kW micro-grid. The military needs to easily and reliably set up compact micro-grids for a variety of power-supply applications. The emergence of commercially available turbo-alternator products in the 10-50 kW range has created an opportunity to fill this important military need. Multiple micro-turbines will be operated only when there is an electrical demand. The turbines must start quickly, and immediately and automatically connect to the AC micro-grid. The problem is that currently available control technologies do not meet the requirements for such micro-grids. A Phase I goal is to demonstrate a practical method for reliably and efficiently “mechanically paralleling” micro-turbines. An equally important problem is that commercially available turbogenerators are not necessarily designed to withstand the mechanical loads that will be imposed by rapid mechanical paralleling. Therefore, a related Phase I goal is to evaluate changes required to turbogenerators to allow micro-grid operation. A successful Phase II project will conclude with a micro-grid demonstration by MSI and its subcontractor, Fairmount Automation.

Keywords:
Turbogenerator, Mechanical Paralleling, Control System, Torsional Analysis, Transient Response, Gas Turbine, Foil Bearings, Synchronization

The project goal is to enable the electrical outputs of multiple, very compact turbogenerators in the 10-50 kW range to be combined (“mechanically paralleled”) in order to create a compact, stable, reliable, and efficient microgrid capable of providing up to 500 kW of “island” power that can be subject to rapid transients, without suffering degradation. To accomplish this, MSI has assembled a team of experienced and accomplished individuals in the fields of electrical control, high rotational speed electrical power generation, and rotordynamics and mechanical behavior, and has established a cooperative relationship with a DoD contractor/ supplier of microturbine generators. Analytical methods are being applied that consist of simplified but robust approaches in Phase I and high fidelity numerical techniques in Phase II involving comprehensive nonlinear finite element and finite difference multiphysics (i.e. simultaneous electromagnetic/stress/deflection/vibration) analysis of detailed component and fully assembled system geometries. Specialized testing will be used to validate the analysis and simulation tools. Phase II will conclude with a demonstrated rapid paralleling control system applicable to a wide range of systems, a modified set of small turbojet generators operating as a microgrid, plus rotor system design modifications and a scaling methodology applicable to larger turbojet generators.

Keywords:
Turbogenerator, Mechanical Paralleling, Control System, Electro-Mechanical Analysis, Transient Response, Gas Turbine, Synchronization