Numerical control based on the FPGA components of a synchrone machine

There have been major revolutions in variable-speed electric drives, notably in the performance enhancement of power electronics components and in the use of new digital solutions as a basis for implementing control algorithms. The first control algorithms were implemented using analog solutions. Thanks to their speed and continuous operation, these solutions were able to achieve high-bandwidth controls. However, they lacked reliability due to their sensitivity to disturbances and variations in control parameters linked to the thermal constraints of analog control circuits. To overcome these drawbacks, digital solutions were the natural choice. The first digital implementations of electrical machine control algorithms were made using microcontrollers, microprocessors and DSPs (Digital Signal Processors). These digital solutions solved the problems associated with the use of analog controls. They also offered significant cost benefits and greater design flexibility. However, despite the advantages offered by these digital solutions, some of the benefits offered by analog implementations have been lost. This is mainly due to the fact that the discretization and quantization of the control algorithms to be implemented, as well as computation time delays, deteriorate control performance in terms of correction speed and control resolution.

Technological advances in microelectronics have made new digital solutions available, such as FPGAs (Field Programmable Gate Arrays) and ASICs (Application Specific Integrated Circuits), which can be used as digital targets for implementing control algorithms. The inherent parallelism of these new solutions and their high computing capacities mean that calculation times are negligible, despite the complexity of the algorithms to be implemented. The use of these hardware solutions therefore makes it possible to recover certain analog performances while retaining the advantages of digital solutions. What's more, these solutions meet the new requirements of modern controls. Indeed, in addition to improving control performance by reducing calculation times, the parallelism of hardware solutions means that several algorithms can be integrated on a single target, providing different functions and working independently of each other. Furthermore, compared with the standard digital solutions used in variable-speed electric drives, FPGAs offer the designer access to the hardware architecture, since it is the designer himself who is responsible for its design. Nevertheless, this new degree of freedom presents the designer with an additional difficulty, since it is up to him to implement the control architecture. To this end, when implementing algorithms on FPGA targets, it makes sense to rely on a more automated and less intuitive methodical approach. This approach...