Novel FCS-MPC low switching frequency control method

Abstract

The invention provides a novel FCS-MPC low switching frequency control method, and relates to the field of the control of electric power and electronic converters. The method includes following steps: sampling a practical value and applying an optimal switch combination selected at the previous period; controlling time-delay compensation; realizing current prediction in two future control periods based on a prediction time domain extending principle; evaluating the selected effective switch combination according to a system value function, and selecting the optimal switch combination for the effect in the next control period; and repeating the above process in the next control period. According to the method, unnecessary switching of switches between adjacent control periods is effectively avoided, the switching frequency of the system is reduced, the method is not limited by an electric power and electronic converter topology structure and a prediction model and is irrelevant to the problem of setting of a weight factor, the algorithm concept is clear, the realization is easy, the operation burden of the control system is not increased, and the dynamic performance of the control system is not affected.

Description

technical field [0001] The invention relates to the technical field of power electronic converter control, in particular to a low switching frequency control method suitable for an FCS-MPC control system. Background technique [0002] For power electronic converters, especially high-power multi-level frequency conversion devices, the switching loss of switching devices has become the most important power loss part of the frequency conversion device with the increase of its voltage level and power level. The low switching frequency operation of the device can not only effectively reduce its own power loss, but also help to increase the output power of the device and improve its output current capability. Therefore, the development of high-power multi-level power electronic converters and their popularization and application in energy saving and consumption reduction must first solve the problem of low switching frequency control. [0003] In the power electronic converter co...

AI Technical Summary

Problems solved by technology

This method has a clear concept and is easy to understand, but there is a problem that the weight coefficient is difficult to set, and it can only achieve low switching frequency control in one control cycle in the future

To achieve low switching frequency control in multiple control cycles in the future, the existing method is to adopt a multi-step predictive control method, but the multi-step predictive method will increase the amount of predictive calculations exponentially, resulting in a heavy computational burden on the controller, which is difficult to achieve. accomplish

[0004] From the analysis of the research status of low switching frequency at home and abroad, the scheme based on FCS-MPC has shown excellent performance in the control of low switching frequency of converters with different topologies due to its inherent multi-constraint conditions and multi-objective task processing capabilities. Strong adaptability and control potential, but so far there is no low switching frequency control method that is suitable for all power electronic converter topologies, has no weight factor tuning problem, and does not affect the calculation amount of the FCS-MPC control system.

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