Hybrid Vehicle Angle Reference Calibration for Vibration Reduction

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing systems in hybrid vehicles lack precise determination of the angular reference between the internal combustion engine and the electric motor, leading to inefficiencies in reducing vibration excitations in the motor-transmission system.

Innovation Solution

An angular position detection device using a crankshaft sensor for absolute engine position and a rotor position sensor for relative motor position, with electronic control units to determine and adjust the mechanical angular reference between the two, incorporating a learning and calibration function to correct errors and improve accuracy.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Device complexity

If a constant angular offset determined when the internal combustion engine is stationary or slowly rotating is used, then the device complexity is reduced, but the measurement precision of the angular reference deteriorates

Engineering Contradiction:
Improveangular reference determinationVSAvoidangular reference precision
Core Design Contradiction:
Device complexityVSMeasurement precision

Solution Approach 1:

The patent applies preliminary action by determining the mechanical angular reference relationship between the internal combustion engine and electric motor during stationary or slow-rotation states before normal operation begins. This preliminary determination captures the true mechanical angular offset without vibration interference, storing it as a constant value for subsequent use during dynamic operation, thus resolving the contradiction between simplicity and precision.

Inventive Principle:
Principle #10Preliminary action

2Ease of operation

If the angular reference is determined without considering pole jumps, then the ease of operation is improved, but the reliability of the angular position detection deteriorates

Engineering Contradiction:
Improveangular reference calculationVSAvoidangular position detection
Core Design Contradiction:
Ease of operationVSReliability

Solution Approach 1:

The patent implements feedback by continuously monitoring the angular position relationship between engine and motor, detecting pole jump events when the calculated angular offset exceeds expected thresholds. When pole jumps are detected, the system automatically corrects the angular reference by identifying the correct reference pole and adjusting the offset accordingly, ensuring reliable angular position detection while maintaining operational simplicity through automated correction mechanisms.

Inventive Principle:
Principle #23Feedback

Data Source

PatentEP4313649B1Angular position detection device in a hybrid vehicle
Publication Date: 2025.10.22 BAYERISCHE MOTOREN WERKE AG
  • EP4313649B1 patent drawingFigure 1
  • EP4313649B1 patent drawingFigure 2

AI summary

The invention relates to an angular position detection device in a hybrid vehicle with an internal combustion engine, having a crankshaft sensor for detecting an absolute internal combustion engine angular position with respect to a defined position mark, having an electric machine, having a rotor position sensor for detecting a relative electric machine angular position based on a reference point, in particular a reference pole comprising a plurality of identical rotor poles, and having at least one electronic control unit. The at least one control unit is configured such that the absolute internal combustion engine angular position and the relative electric machine angular position are detected when the internal combustion engine is stationary and the electric machine is stationary and such that a mechanical angular reference of the internal combustion engine with respect to the electric machine is determined, on the basis of these angular positions, as an angle difference between the position mark and an initial reference point and is stored.