PI (Proportional-Integral) partition control method for inverter system

Abstract

The invention discloses a PI (Proportional-Integral) partition control method for an inverter system, which comprises the steps of performing partition division on the working state of the inverter system, judging the current working state of the inverter system when the inverter system is in operation, and selecting a corresponding PI parameter group to perform control on the inverter system according to the current working state of the inverter system. PI control at the DC side and the AC side of the system is carried out in a partition mode according to a predetermined judgment mechanism; asoft start interval, a large load interval, a large load reduction interval and a stable working interval respectively correspond to different PI parameter groups; and each parameter groups include adifferent proportional coefficient Kp, integral coefficient Ki and PWM duty ratio saturation amplitude limit Lim, thereby enabling the system to always maintain the optimal state when being suddenlyswitched in different working conditions such as no load, light load, heavy load and full load, not only have fast response, but also have safe steady-state output.

Description

technical field [0001] The invention relates to the technical field of new energy and power electronics, in particular to a PI partition control method of an inverter system. Background technique [0002] The inverter is an inverter device that realizes DC to AC. Common inverter control methods include PI (proportional integral), PR (proportional resonance), sliding film, and repetitive control. Among them, the PI algorithm is classic and easy to implement, and is the most common method in current practical applications. [0003] The inverter system needs to respond quickly when the system load changes greatly in order to restore stability as soon as possible. In order to reduce the deviation as soon as possible, speed up the response speed, and shorten the adjustment time, the proportional coefficient Kp in the PI regulator should be large and the integral coefficient Ki should be small. However, such parameters are easy to cause side effects such as overshoot and oversho...

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Problems solved by technology

However, such parameters are easy to cause side effects such as overshoot and overshoot or periodic oscillation; and if you choose milder parameters, it will cause the problem of slow dynamic response

Sometimes, a set of PI parameters suitable for full load adjusted through engineering setting and experience will always fail to work stably once light load or no load

It is necessary to respond quickly, but also to be stable and reliable. A single set of control parameters is often unable to take into account various working conditions, and only a set of relatively suitable parameters can be selected as a compromise. This is because it is difficult to control the control parameters of the inverter system during the tuning process. technical problems

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