Hybrid Engine Speed Transition Control to Suppress Intake Noise
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Irregular sound is generated from the intake system of an engine when motoring control is shifted to firing control and the engine rotational speed is decreased to a predetermined rotational speed by motor torque, as existing technologies do not effectively manage the transition.
Innovation Solution
A control method for a series hybrid car that sets the torque generated by the internal combustion engine lower than the required torque within a predetermined rotational-speed range during the transition from non-combustion to combustion mode, using a first electric motor to decrease the engine rotational speed to a target speed within that range.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If the engine rotational speed is rapidly decreased from motoring control to firing control to consume regenerative power, then the power consumption efficiency is improved, but irregular sound is generated from the intake system
Solution Approach 1:
The control device performs preliminary action by setting the engine rotational speed to a target value that prevents irregular sound before the transition to firing control is completed. The target rotational speed is calculated based on intake system resonance characteristics, and the engine speed is controlled to approach this target gradually, avoiding the harmful sound phenomenon while maintaining efficient power consumption.
Solution Approach 2:
The invention changes the operational parameters of the engine during transition by dynamically adjusting the target rotational speed based on the relationship between engine speed and intake system resonance. The control device modifies the engine rotational speed parameter to avoid resonant frequencies that cause irregular sound, while still achieving the desired power consumption efficiency through controlled deceleration to the calculated target speed.
2Object-affected harmful factors
If the engine rotational speed is maintained at high speed to avoid intake system irregular sound, then the sound quality is improved, but the power consumption efficiency decreases
Solution Approach 1:
The control device applies dynamics by continuously adjusting the target rotational speed based on real-time operating conditions and the relationship between engine speed and intake system resonance. Rather than maintaining a fixed high speed, the system dynamically optimizes the rotational speed trajectory during transition, allowing the engine to decelerate to the calculated target speed that prevents irregular sound while minimizing unnecessary power consumption.
Solution Approach 2:
The invention uses skipping by rapidly transitioning through the problematic rotational speed range where intake system irregular sound occurs. The control device calculates the target rotational speed that avoids resonance and controls the engine to skip through the harmful speed range quickly, reaching the target speed efficiently without prolonged exposure to conditions that generate irregular sound or waste energy.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach minimizes irregular sound from the engine intake system during the transition from motoring to firing control, reducing occupant discomfort and maintaining smooth engine operation.
Implementation Method 1
a rotational speed of an internal combustion engine shifting from a non-combustion mode to a combustion mode is decreased to a rotational speed within a predetermined rotational-speed range by a first electric motor
Implementation Method 2
a torque generated by the internal combustion engine is set lower than a required torque within a predetermined rotational-speed range for the internal combustion engine in the combustion mode
Data Source
Figure 1
Figure 2
Figure 3
AI summary
In an electric device control method and an electric device of the present invention, during a period in which a rotational speed of an internal combustion engine shifting from a non-combustion mode to a combustion mode is decreased to a rotational speed within a predetermined rotational-speed range by a first electric motor connected to the internal combustion engine, a torque generated by the internal combustion engine is set lower than a required torque within the predetermined rotational-speed range for the internal combustion engine in the combustion mode.