Optimal speed torque output method of asynchronous motor for electric bus based on random forest regression algorithm

Abstract

The invention discloses an optimal speed torque output method of an asynchronous motor for an electric bus based on a random forest regression algorithm. The method comprises steps of firstly, establishing an asynchronous motor vector control system based on a current ratio output model; secondly, establishing an analytical model of the maximum torque output according to a limiting condition of the maximum voltage (Usmax) and the maximum current (Ismax); thirdly, analyzing an excitation current torque current change law corresponding to the maximum torque output under different operating conditions, establishing a voltage closed-loop vector analysis model, and embedding a vector control system; then, establishing an AVL (AVL list GmbH) experimental platform, acquiring actually measured sample data, and establishing a random forest regression (RFR) model using the operating condition parameters as input and output; and finally, embedding the regression model in the vector control systemto realize the regression of the motor operating in different conditions, namely the optimal speed torque control. The method has accurate matching current, does not need to divide the asynchronous motor into operating areas, and improves the stability of the speed torque output.

Description

technical field [0001] The invention relates to the technical field of asynchronous motors, in particular to a method for outputting optimal speed and torque of asynchronous motors for electric buses based on a random forest regression algorithm. Background technique [0002] Common asynchronous motor control methods include direct torque control (Direct torque control, DTC) and vector control (vector control, VC). DTC performs Bang-Bang control on torque and stator flux linkage, which avoids the transformation of rotating coordinates and makes the structure of the control system simple, but it is easy to generate torque ripple, and the speed regulation width is not high; VC decouples torque and rotor flux linkage Control, easy to achieve continuous and stable torque control, wide speed range. Therefore, according to the operation of electric buses in all working conditions (electric buses operate in different environments, there are three typical working conditions: conges...

AI Technical Summary

Problems solved by technology

The disadvantages of the existing technology are: 1. Formula derivation is required, which is highly dependent on motor parameters and has many influencing factors

2. Multiple PI regulators are required to control the field weakening area (the area above the rated speed), the system is complex and parameter setting is difficult

3. The actual input Inaccurate, resulting in the problem of response lag in the output voltage vector after passing through the PI controller

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