AC Rotary Machine Control Mode Switching for Ripple and Loss Reduction
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Solution Overview
Problem
Existing AC rotary machine control methods face increased processing load due to constant loss calculations, and result in large ripple components of bus and winding currents, leading to increased losses.
Innovation Solution
An AC rotary machine controller that switches between three control modes based on operating state: phase current ripple suppression, bus current ripple suppression, and switching loss suppression, using voltage command calculations and PWM control to minimize ripple components and losses.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If loss calculation and comparison is performed constantly to select the drive method with lowest loss, then the optimal drive method is selected, but the processing load increases
Solution Approach 1:
The control method dynamically switches between different control modes (first control mode with one inverter, second control mode with the other inverter, third control mode with both inverters) based on operating conditions such as rotational speed and torque requirements, rather than constantly calculating and comparing losses. This dynamic adaptation allows the system to achieve near-optimal performance while significantly reducing processing load.
Data Source
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AI summary
To provide an AC rotary machine controller, a vehicle apparatus, and an electric power steering apparatus which can achieve appropriately reduction of the ripple component of the bus current, reduction of the ripple component of the winding current of each phase, or reduction of the switching loss. An AC rotary machine controller controls an AC rotary machine provided with one set or a plurality of sets of three-phase windings; switches a first control mode, a second control mode, and a third control mode, based on an operating state of the AC rotary machine, for each set; executes a phase current ripple suppression control in the first control mode; executes a bus current ripple suppression control in the second control mode; and executes a switching loss suppression control in the third control mode.