|Died||27 October 2017 (aged 84)|
|Alma mater||University of Manchester|
|Known for||Switched reluctance drives|
|Awards||Faraday Medal (1990)|
IEEE Edison Medal (2005)
|Institutions||University of Leeds|
Peter John Lawrenson, FIEE, FIEEE, FRS, FREng (12 March 1933 – 27 October 2017) was an Emeritus Professor of Electrical Engineering at the University of Leeds who pioneered and championed the development of switched reluctance drive technology. He also made significant contributions to the analysis and computation of magnetic fields and electrical machines in general, writing several notable text books along with colleagues Kenneth Binns , Martyn Harris and J. Michael Stephenson  and latterly with C.W. ("Bill") Trowbridge  .
Lawrenson was born in Prescot, Lancashire, and educated at the University of Manchester from which he held the degrees of BSc, MSc and DSc. From 1956 to 1961 he was a research engineer at GEC. His early published activities include work on linear electrical machines with Eric Laithwaite, in which the linear induction motor was considered as a propulsion means for the shuttle in textile weaving machines. ,
In 1961 Lawrenson was appointed a Lecturer in Electrical Engineering at the University of Leeds, from where his publications show growing interest in reluctance machines - initially AC-fed synchronous reluctance motors       and later doubly-salient synchronous machines such as stepper motors (resulting in numerous further publications throughout the 1970's, often co-authored with research students and colleagues including Austin Hughes, Michael Stephenson, Paul Acarnley, Philip Blenkinsop, Norman Fulton and Jasmin Corda, to name but some of his co-workers). The first seminal paper on switched reluctance machines was published in 1980 . He remained at Leeds for 30 years, being promoted to Reader in 1965 and Professor of Electrical Engineering in 1966. He retired from his chair in 1991 with the title Emeritus Professor, in order to devote his full-time attention to the growing business he had co-founded in Leeds, Switched Reluctance Drives Ltd. 
Lawrenson is considered the father of the switched reluctance motor and associated drive technology. Based on research work that had been carried out jointly by the University of Leeds and the University of Nottingham, in 1980 he and three colleagues (Michael Stephenson, Bill Ray and Rex Davis) established a design, technology development and licensing business, Switched Reluctance Drives Ltd. Initially based in Leeds, UK, the company was sold to Emerson Electric in 1994, and whilst still based in the north of England at Harrogate, it became a wholly owned subsidiary of Nidec Corporation of Japan in 2010 (to whom Emerson sold its entire US-based motor interests). The former SR specialist unit was transferred to Nidec's Drive Systems subsidiary in 2016, but was much reduced in size and scope in 2019 when Nidec ended all manufacturing at the Harrogate site and greatly downsized the (until then) substantial engineering team. Nidec Drive Systems continues to supply SR motors and inverters, but presently only for customer-specific industrial and off-road vehicle applications.
Lawrenson was the recipient of the Faraday Medal of the Institution of Electrical Engineers, the ESSO Energy Gold Medal of The Royal Society and the J.A. Ewing Gold Medal of the Institution of Civil Engineers. He was elected a Fellow of the Royal Academy of Engineering (FREng) in 1980 and of the Royal Society (FRS) in 1982. Lawrenson won the IEEE Edison Medal in 2005 For outstanding contributions to the field of electrical machines, most notably the development and commercialization of switched reluctance drives.
- "List of Fellows".
- Peter John Lawrenson
- "Analysis and Computation of Electric and Magnetic Field Problems", K.J. Binns and P.J. Lawrenson, Pergamon Press, 1963
- "Per-Unit Systems with Special Reference to Electrical Machines (IEE Monograph Series, #4)", M.R. Harris, P.J. Lawrenson and J.M. Stephenson, Cambridge University Press, 1970
- "The Analytical and Numerical Solution of Electric and Magnetic Fields", K.J. Binns, P.J. Lawrenson and C.W. Trowbridge, Wiley-Blackwell, 1992
- "A self-oscillating induction motor for shuttle propulsion", E.R. Laithwaite and P.J. Lawrenson, Proceedings of the IEE - Part A: Power Engineering, Volume: 104, Issue 14, 1957, p.93
- "Shuttle propulsion", E.R. Laithwaite and P.J. Lawrenson, Journal of the Institution of Electrical Engineers, Volume 3, Issue 26, 1957, p.96-97
- "A new unexcited synchronous machine", P.J. Lawrenson and L.A. Agu, Proceedings of the Institution of Electrical Engineers, Volume 110, Issue 7, 1963, p.1275
- "Reluctance machines", P.J. Lawrenson and L.A. Agu, IEE Electronics and Power Journal, Volume 10 Issue 8, 1964, p.264-265
- "Theory and performance of polyphase reluctance machines", P.J. Lawrenson and L.A. Agu, Proceedings of the Institution of Electrical Engineers, Volume 111, Issue 8, 1964, pp.1435-1445
- "Low-inertia reluctance machines", P.J. Lawrenson and L.A. Agu, Proceedings of the Institution of Electrical Engineers, Volume 111, Issue 12, 1964, pp.2017-2025
- "Development and application of reluctance motors", P.J. Lawrenson, IEE Electronics and Power Journal, Volume 11, Issue 6, 1965, pp. 195-198
- "Two-speed operation of salient-pole reluctance machines", P.J. Lawrenson, Proceedings of the Institution of Electrical Engineers, Volume 112, issue 12, 1965, pp.2311 - 2316
- "Variable-speed switched reluctance motors", P.J. Lawrenson, J.M. Stephenson, P.T. Blenkinsop, J. Corda and N.N. Fulton, IEE Proceedings B - Electric Power Applications, Volume 127, Issue 4, 1980. pp. 253-265
- University of Leeds, List of Emeritus Professors Archived 2012-09-26 at the Wayback Machine
- Debrett's Biography
- "IEEE Edison Medal Recipients" IEEE official website. Retrieved 24 December 2010
- "Peter Lawrenson". IEEE Global History Network. IEEE. Retrieved 25 July 2011.