Semiconductor device and motor control program
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing semiconductor devices face challenges in reducing memory capacity while accurately suppressing torque vibration in motors, often requiring lower resolution or fewer compensation tables, which compromises accuracy.
Innovation Solution
A semiconductor device with a compensation-value completion circuit that uses a completion function to calculate torque compensation values based on a compensation value table, reducing memory usage by approximating polynomial functions to derive compensation values for any rotation angle, thereby updating the compensation table effectively.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If the resolution of the rotation angle or the compensation value is decreased, or the number of tables is decreased to reduce memory capacity, then the used memory capacity is reduced, but the accuracy in suppressing the torque vibration is decreased
Solution Approach 1:
The patent changes the parameter representation from discrete table lookups to continuous polynomial function evaluation. By representing compensation values as polynomial functions of rotation angle rather than discrete table entries, the system achieves continuous high-resolution compensation while storing only polynomial coefficients, dramatically reducing memory requirements while maintaining or improving suppression accuracy.
Solution Approach 2:
The patent creates a mathematical model (polynomial function) that copies and generalizes the compensation pattern observed in discrete measurements. Instead of storing all possible compensation values, the system stores a compact polynomial representation that can generate accurate compensation values for any rotation angle, effectively copying the essential compensation behavior in a space-efficient form.
2Measurement precision
If basic compensation data is created for each rotation speed using multiple compensation tables, then torque vibration suppression accuracy is improved, but the used memory capacity increases
Solution Approach 1:
The patent transforms the storage requirement from multiple full-size compensation tables to a single compact polynomial coefficient set. By changing the representation parameter from discrete compensation values to polynomial coefficients, the system maintains the ability to provide speed-specific compensation while reducing memory usage from storing complete tables to storing only coefficient parameters.
Solution Approach 2:
The polynomial function serves multiple purposes: it provides compensation values for any rotation angle, can be adjusted for different rotation speeds by modifying coefficients, and maintains continuous accuracy across the entire rotation range. This single universal representation replaces multiple specialized tables, achieving multi-functionality with reduced memory capacity.
Data Source
AI summary
A RAM stores a compensation value table in which a torque compensation value of each of discrete rotation angles that are discrete rotation angles of a motor is registered. A processor performs a step (a) of extracting a vibration component based on speed difference between a speed command value and a value of a rotation speed of the motor, and of calculating and deriving an update amount of each of the discrete rotation angles required for suppressing the vibration component. The processor further performs a step (b) of updating the compensation value table based on the update amount of each of the discrete rotation angles. The processor further performs a step (c) of calculating and deriving the torque compensation value of each any rotation angle of the motor by use of the compensation value table and a completion function, and of reflecting it to a motor control signal.