Control Techniques began life in 1973, when Wheatley and his fellow founders, Ken Briggs and Kevin Curran, set up a drives manufacturing company, KTK (based on their initials). They had previously worked together at Mawdsley’s, an engineering firm that was involved in the emerging drives business. But the three felt it was not innovating fast enough, and they could do better working for themselves. Wheatley, a former coal miner, was responsible for sales, Briggs for product design, and Curran for business management.

In 1979, KTK moved to Newtown in mid-Wales, where it was offered rent-free factory space by the Mid-Wales Development Corporation.

In 1982, KTK invented the world’s smallest drive. In 1985, KTK changed its name to Control Techniques and in 1989 launched the world’s first digital DC drive, the Mentor. In the same year, CT created the world’s first practical flux vector AC drive, the Commander CD.

In 1990, Wheatley was awarded an OBE for service to the electronics industry.

In 1995, Control Techniques was acquired by Emerson Electric, which fired Wheatley two years later. He then became chairman of a new drives company, Focus Dynamics, but had to resign when Emerson won a court case in which it alleged that Wheatley had broken an undertaking not to re-enter the drives business for a fixed period after leaving Emerson.

He later counter-sued the American company for wrongful dismissal, claiming around £9m in damages, but in 1999 lost his case in the High Court.

In the same year, he bought Focus Dynamics’ drives activities following a takeover of Focus by Breckenburn, a company co-owned by Wheatley and the rail entrepreneur Sandy Anderson. The Focus Dynamics board had tried to fend off the £5.3m bid, suggesting that it undervalued the company. They even threatened to break up the company rather than sell it to Breckenburn.

In 2001, Focus Dynamics was put into liquidation after Wheatley failed to raise £22m to secure the company’s future. Most of the money was needed to fund two large acquisitions that Wheatley had been planning – including the DC drives business of a big name in the sector. Wheatley had managed to raise £15m before time ran out.

After the failure of Focus Dynamics, Wheatley went into semi-retirement. He later suffered a severe gardening accident which led to the loss of a leg.

In 2017, Control Techniques as acquired by the Japanese motors giant, Nidec.

In a statement following Trevor Wheatley’s Death, Control Techniques said it was “deeply saddened to learn of the passing of one of its founding fathers, leaders and pioneers.” It described him as “a true innovator in every sense, who took Control Techniques to world status. Trevor was a man of action, committed to the continuous development of drives.

“Trevor was never afraid to stand out,” the statement added. “This philosophy to be courageous, bold, and daring to be different is one that we continue to this day. Without Trevor, there wouldn’t be an us.”