Background

A Tier-1 aerospace manufacturer launched a technology development program for next-generation Variable Speed Constant Frequency (VSCF) converters. The technology needed to be quickly matured from TRL3 to TRL6. New technologies and control algorithms were required to meet state-of-the-art performance objectives. Preliminary control concepts had been developed and simulated by company researchers at nominal operating conditions. Further development was required to meet performance requirements over the entire operational envelope of an aircraft Electrical Power Generation System (EPGS). Laboratory validation testing was required to meet TRL4, TRL5 and TRL6 readiness criteria.

Result

Kaney provided a controls subject matter expert to work collaboratively with the customer.  Detailed models were created and used to define a variety of worst-case operating conditions.  Simulations at the worst-case operating conditions showed that new control algorithms would be needed to meet performance targets. Kaney developed these control algorithms on behalf of the customer, and the algorithms were subsequently baselined into the design.

An off the shelf rapid prototyping controller was used in conjunction with a power converter breadboard to perform Hardware in the Loop (HIL) validation testing. The control algorithm design was iteratively improved multiple times and changes were validated on the HIL test bed.  By testing the control algorithms prior to manufacture of a custom control circuit card, cost and schedule savings were both realized.

 Kaney’s Involvement

• Developed innovative control algorithms to solve performance challenges, overcoming issues that could have become “show-stoppers.”  As a result, three patent applications (assigned to the customer) were issued.
• Wrote detailed Technical Memoranda documenting the control algorithm design, principles of operation, rationale for design decisions and stability margins.
• Developed average and switching models of the power converter, controller and a variety of power system loads.
• Provided a detailed change log, documenting developmental revisions to control algorithms and system models.
• Conducted lab testing to assess system performance with linear loads, non-linear loads, unbalanced loads and short-circuits.

Maintained the COTS HIL control system used for controls development.