Principal Engineer – Software and Electronics (June 2009 – April 2011)

Whisper Tech Limited’s vision is the Stirling engine-based WhisperGen™ heat and power system – a smarter way to provide home heat and power with the added benefit of reduced environmental impact. This micro combined heat and power (microCHP) system is produced in both on-grid and off-grid forms.

This role is responsible for the technical leadership, development and management of a small team of multi-disciplined embedded engineers that designed and developed the control power electronics for the WhisperGen heat and power system.

The role was primarily to take the Electronics and Software Department from a start-up group to a fully professional Department using mature processes and procedures as it looks for more opportunities to grow in size and capability.

Key Points

• Provide clear technical direction for the Electronics and Software Department.
• Working with other Engineering disciplines to establish a professional development life cycle for Electronics and Software.
• Actively maintain and develop new relationships with professionals outside of the business that will be required for consultancy from time to time.
• Responsible for the delivery of technical work to the project plan.
• Project planning the Electronics and Software components of larger projects.
• Perform analysis and create industry best practice processes and development life cycles for the Electronics and Software Department.
• Work closely with QA Manager and other Engineering groups to agree on Software Release and Hardware Revision processes.
• Instigate an issue tracking and work flow management system for the Electronics and Software Department.

My technical involvement covered two major projects. The first was a re-architecture of a piece of safety critical firmware that had been written by a previous junior engineer was found to have some potentially serious issues. The firmware running on an Atmel CPU was being used to measure and determine if the product was trying to generate electricity and had become isolated from the electricity grid. A circuit, called GIMU (Grid Impedance Measurement Unit) would try to determine if the grid had disappeared by measuring tiny changes in the impedance at the generator.

The second piece of technical work involved creating a test system (a linux pc) which could test the engine control software and electronics by simulating a real stirling engine. A stirling engine is a very complex device to control and testing the various failure modes on a real engine would take many hours due to the complex mechanical machinery and environmental aspect. The test suite comprised of a network interfaced virtual stirling engine, and a test engine which took test scripts and assertions. By adding a test mode to the control electronics to effectively speed up time, a full safety test run could be completed in 2 hours, something that previously took one mechanical/electrical engineer over a week. The virtual stirling engine could also be used to diagnose issues on a real engine, by taking control of individual or groups of a real stirling engine when connected to a real running unit.