Motor Driving System Angle Prediction via Inclination Data

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing motor driving systems for electric vehicles face challenges in accurately predicting the motor shaft angle when the angle detector fails, especially in varying road conditions, leading to potential safety issues due to incorrect torque generation and unintended acceleration or deceleration.

Innovation Solution

The system employs a learning circuit that records and uses data from vehicle speed, torque, and vehicle inclination angle to predict the motor shaft angle, allowing for proper motor control even in failure scenarios, by associating these parameters in a storage apparatus and generating control signals based on learned data to adapt to different driving environments.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If wheel speed-enabled motor angle prediction means is used to predict motor shaft angle when angle detector fails, then motor can still be controlled in failure condition, but prediction accuracy deteriorates in inclined or gradient road conditions

Engineering Contradiction:
Improvemotor control reliabilityVSAvoidmotor shaft angle prediction accuracy
Core Design Contradiction:
ReliabilityVSMeasurement precision

Solution Approach 1:

The patent introduces vehicle inclination angle detector as an intermediary device to detect the inclination of the vehicle body. This intermediary sensor provides additional information about the traveling environment that is then used to correct the motor shaft angle prediction, resolving the accuracy deterioration caused by wheel speed mismatches in inclined conditions

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent implements a feedback mechanism where the detected vehicle inclination angle is fed back to the motor shaft angle prediction means. The prediction means uses this inclination information to correct its predictions, creating a closed-loop system that compensates for environmental factors and maintains accuracy despite angle detector failure

Inventive Principle:
Principle #23Feedback

2Device complexity

If motor shaft angle is predicted solely on basis of wheel speed, then system complexity remains low, but torque generation becomes incorrect in varying road conditions

Engineering Contradiction:
Improveprediction system complexityVSAvoidtorque generation reliability
Core Design Contradiction:
Device complexityVSReliability

Solution Approach 1:

The patent applies preliminary action by detecting the vehicle inclination angle in advance using the inclination angle detector before the motor shaft angle prediction is performed. This preliminary detection allows the system to proactively compensate for environmental effects rather than reacting to errors after they occur

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The patent makes the motor control system universal by enabling it to operate reliably across diverse traveling environments (flat roads, inclined roads, gradient conditions) through the multi-functional approach that combines wheel speed detection with vehicle inclination detection and integrated prediction

Inventive Principle:
Principle #6Universality (Multi-functionality)

Data Source

PatentEP3459780B1Motor driving system and motor driving method
Publication Date: 2021.11.17 RENESAS ELECTRONICS CORP
  • EP3459780B1 patent drawingFigure 1
  • EP3459780B1 patent drawingFigure 2
  • EP3459780B1 patent drawingFigure 3~4

AI summary

Provided are a motor angle detector for detecting a motor angle, a current detector for detecting a motor current value to drive a motor, a vehicle inclination angle detector for detecting a vehicle inclination angle, a motor control circuit for outputting a control signal to control the driving of the motor, and a storage apparatus. The storage apparatus stores data obtained by associating the motor current value, a setting value in the motor control circuit for outputting the control signal, the vehicle inclination angle, and the motor angle at a first time with each other, and the motor control circuit controls the driving of the motor on the basis of information of the motor current value and the vehicle inclination angle at a second time and the data at the first time.