John D Ainsworth

Title: Innovations of John D Ainsworth

Introduction

John D Ainsworth is a notable inventor based in Stafford, GB. He has made significant contributions to the field of electrical engineering, particularly in the development of multilevel converters. With a total of five patents to his name, Ainsworth's work focuses on minimizing harmonic content in converter systems.

Latest Patents

One of Ainsworth's latest patents is a switching control arrangement for a multilevel converter. This innovation minimizes the harmonic content of the converter voltage or current through both open-loop and closed-loop control of the timing of the switching of the GTOs associated with energy-storage components like capacitors. In the first open-loop arrangement, the converter current is quantized over its working range, with different threshold values based on the quantization values of the current. The second open-loop arrangement provides continuous, non-quantized control based on a quadratic approximation to the desired current-dependent behavior of the GTO switching angles. The third, closed-loop arrangement offers different GTO-switching threshold levels controlled by a Fourier integration process to nullify specific harmonics. This control arrangement is applicable to chain or stacked-capacitor multilevel converters and can be utilized in SVC applications or scenarios where the converter draws both real and reactive power.

Another significant patent by Ainsworth is for a multilevel converter with capacitor voltage balancing. This converter features a set of series-connected capacitors and associated series-connected switching elements. It employs a main control loop to manage aspects of an AC system, such as busbar voltage, by controlling the switching times of the elements. Additionally, it includes subsidiary control loops to establish a desired relationship between mean DC voltage levels on the capacitors. These loops combine signals proportional to DC voltage levels and tap currents to modulate the timing of switching elements connected to capacitors that are out of balance, preventing runaway voltage conditions.

Career Highlights

Throughout his career, Ainsworth has worked with prominent companies, including Associated Electrical Industries Limited and Gec-Alsthom Limited. His experience in these organizations has contributed to his expertise in electrical systems and innovations.

Collaborations

Ainsworth has collaborated with various professionals in his field, including David R Trainer, enhancing his work through shared knowledge and expertise.

Conclusion

John D Ainsworth's contributions to electrical engineering through his innovative patents have significantly advanced the