Generator Torque Control for Vehicle Start-Stop Voltage Stability

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Vehicles with start-stop systems experience significant voltage dips in the electrical system when electrical consumers are activated during the starting phase due to limited generator torque, which is not adequately addressed by existing technologies.

Innovation Solution

A method and device that detect the operating state of a vehicle and deactivate the limitation of generator torque when in a start-stop mode, ensuring maximum electrical power is available to the electrical system by monitoring communication between the internal combustion engine control unit and generator controller, and using pulse width modulation signals to recognize and respond to the start-stop state.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If generator torque is limited during starting phase, then engine starting is facilitated, but voltage dips occur in electrical system when consumers are switched on

Engineering Contradiction:
Improveengine startingVSAvoidelectrical system stability
Core Design Contradiction:
Ease of operationVSReliability

Solution Approach 1:

The generator control system dynamically adjusts torque limitation based on detected operating states. During start-stop operating state, the system deactivates torque limitation to provide unlimited generator torque, while during normal starting phase, torque limitation remains active. This dynamic adaptation resolves the contradiction by making the torque limitation conditional rather than fixed.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The system changes the torque parameter of the generator based on the detected operating state. When transitioning from starting phase to start-stop operating state, the torque limitation parameter is deactivated, allowing the generator to deliver maximum torque without restriction, thereby preventing voltage dips while maintaining ease of operation during critical periods.

Inventive Principle:
Principle #35Parameter changes

2Reliability

If unlimited generator torque is provided during start-stop operating state, then voltage dips are prevented, but system complexity increases due to state detection and control logic

Engineering Contradiction:
Improveelectrical system stabilityVSAvoidcontrol system complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The control system continuously monitors operating state parameters and uses this feedback to determine whether to activate or deactivate torque limitation. The detector monitors communication between engine control unit and generator controller, and the deactivation device responds accordingly. This feedback mechanism enables automatic adaptation without requiring complex manual intervention or overly sophisticated control algorithms.

Inventive Principle:
Principle #23Feedback

Solution Approach 2:

The generator control system automatically detects its own operating state and self-adjusts the torque limitation setting without external intervention. The system monitors its own operational context and makes appropriate control decisions, reducing the need for additional complex control hardware or software while maintaining electrical system stability.

Inventive Principle:
Principle #25Self-service

3Power

If generator torque limitation is deactivated in start-stop mode, then maximum electrical power is available, but frequent engine starts may cause excessive wear

Engineering Contradiction:
Improveelectrical power availabilityVSAvoidengine durability
Core Design Contradiction:
PowerVSStrength

Solution Approach 1:

The system applies different torque control strategies to different operating states. During start-stop operating state specifically, unlimited torque is provided to prevent voltage dips, while during other operating states, appropriate torque limitation is maintained. This localized approach ensures electrical stability is prioritized only when the vehicle is stationary and engine restart is anticipated, rather than universally, thereby reducing unnecessary stress on the engine.

Inventive Principle:
Principle #3Local quality

Data Source

PatentEP2694798B1Method and device for operating a generator
Publication Date: 2019.12.11 ROBERT BOSCH GMBH
  • EP2694798B1 patent drawingFigure 1~2
  • EP2694798B1 patent drawingFigure 3~4

AI summary

The invention relates to a method for operating a generator for an internal combustion engine of a vehicle, having a starting operating state and a start-stop operating state, wherein a torque of the generator is limited in the starting operating state, comprising: detection (101) of an operating state of the vehicle; and deactivation (103) of a limiting of the torque of the generator, if the detected operating state corresponds to the start-stop operating state.