Study on Energy Harvester Using Dynamic Vibration Absorber ...Œ¯動/RotO...Study on Energy...
Transcript of Study on Energy Harvester Using Dynamic Vibration Absorber ...Œ¯動/RotO...Study on Energy...
Study on Energy Harvester Using Dynamic Vibration Absorber for Automotive Applications
◎Yasuyuki Takamura, Katsuhiro Hirata,
Noboru Niguchi, Masayuki Kato (Osaka University)
Yuki Tojima, Takeshi Tojo,
Hiroki Koguchi, Keisuke Ushida (AISIN SEIKI CO,.Ltd)
EM10
26th July 2018
2Contents
◎Introduction
◎Simulation on drive train components・Frequency characteristics・Decision of the engine speed range harvesting
◎Proposal of the power generation device
◎Power generation simulation of the simple model・Operating theory・Investigation of the effectiveness of the proposed device
◎Conclusion
3Contents
◎Introduction
◎Simulation on drive train components・Frequency characteristics・Decision of the engine speed range harvesting
◎Proposal of the power generation device
◎Power generation simulation of the simple model・Operating theory・Investigation of the effectiveness of the proposed device
◎Conclusion
Problem of noise
Noise during driving
4
Generating mechanism of muffled sound
Engine T/M
Diff
Tire
Driveshaft
Clutch
5
Torque fluctuation(3-cylinders engine)
Inhalation Compression Explosion Exhaust
Vibration control of driving system6
Frequency characteristic of driveshaft
・Muffled sound generates at frequencies higher 15 Hz・All the energy of vibrations is converted into losses such as a heat andsound
Technique
Problem
・Design drive train components not to resonate with the torque fluctuation
General measure against muffled sound
(FF,MT)
Torsional vibration of shaft
→Energy of vibration is consumed as loss of heats
→Decrease the vibrations generated bythe engine torque
Engine T/M
Diff
Tire
Driveshaft
Clutch
Muffled sound
7
Damper
Measure using damper clutch
Torque fluctuation
Proposed device harvesting energy
(FF,MT)
Torsional vibration of shaft
Torque fluctuation Engine T/M
Diff
Tire
Driveshaft
Clutch
Muffled sound
8
Development of a power generation device harvesting energy of vibrations→Decrease muffled sound without losses of
energy→ Utilization electric power generated
Purpose
Power generation device
9Contents
◎Introduction
◎Simulation on drive train components・Frequency characteristics・Decision of the engine speed range harvesting
◎Proposal of the power generation device
◎Power generation simulation of the simple model・Operating theory・Investigation of the effectiveness of the proposed device
◎Conclusion
Simulation on drive train components
In order to simulate the torsional vibrations simply, we use a 2-inertia system model
・Effectiveness harvesting energy utilizing a mechanical resonance
・Relationship between the engine speed and harvested energy
Examination
10
T
1I 2IK
D
1 2
(Engine) (Generation device)
Frequency characteristics
Moment of inertia of the engine [kgm2] I1=0.14
Moment of inertia of the generation device [kgm2] I2=0.07
Synthetic inertia [kgm2] 1
𝐼=
1
𝐼1+
1
𝐼2
Spring constant [Nm/rad] K=Iω2=414(15Hz)
Viscosity coefficient [Nms/rad] D=K/1000=0.414
Frequency of the excitation force is changed from 1Hz to 30Hz,Amplitude of the excitation force is 2Nm, the offset is 5Nm
The excitation force(15Hz)
11
T
1I 2IK
D
1 2
(Engine) (Generation device)
Mathematical model
gen212111 TDKTI
gen212122 TDKI
121gen
2
21
2
21
2
11
2
222
1
2
1
2
11 TTDKII
dt
Torque of the generation device ※ Gain21gen T
12
T
1I 2IK
D
1 2
(Engine) (Generation device)
Frequency characteristics
121gen
2
21
2
21
2
11
2
222
1
2
1
2
11 TTDKII
dt
Input power Harvested energy
It is effective to harvest energy utilizing a mechanical resonance
13
Resonance frequency (15Hz)
Decision of the engine speed harvesting energy
The moment of inertia of the engine [kgm2] I1=0.14
The moment of inertia of the generation device[kgm2] I2=0.007~0.07
The synthetic inertia [kgm2] 1
𝐼=
1
𝐼1+
1
𝐼2
The spring constant [Nm/rad] K=I・ω 2
The viscosity coefficient [Nms/rad] D=K/1000
The frequency of the excitation force is changed from 15Hz, 75Hz,162.5HzThe amplitude of the excitation force is 2Nm, the offset is 5Nm.
Excitation force(15Hz)
14
T
1I 2IK
D
1 2
(Engine) (Generation device)
・harvesting in the lower engine speed ・designing the device so that I2 becomes large
Harvested energyTorsional vibration (I2=0.07)
15Decision of the engine speed harvesting energy
The harvested energy increases
16Contents
◎Introduction
◎Simulation on drive train components・Frequency characteristics・Decision of the engine speed range harvesting
◎Proposal of the power generation device
◎Power generation simulation of the simple model・Operating theory・Investigation of the effectiveness of the proposed device
◎Conclusion
Structure of the proposed device
Yoke 50JN400/JFE Steel
Magnet N42SH/Shin-Etsu Chemical
Number of pole 8
Number of slots 8
Coil turns per teeth 40
Iron stack length[mm] 50
Shaft diameter[mm] 16
Inner rotor length[mm] 6
Teeth length[mm] 16
Teeth width[mm] 10.7
Air gap length[mm] 0.5
Magnet length[mm] 3
Outer rotor[mm] 11
Basic specifications
Outer rotor
Inner rotor
Permanent magnet
Coil
Outer yoke
Inner yoke
Shaft
Generation device
17
Analysis model and conditions
Analysis model(Stable point)
Analysis conditions
Number of elements 35460
Number of nodes 13946
Number of steps 91
Remanence of Magnet[T] 1.3
CoilsNumber of turn per
teeth40
18
Analysis result
Cogging torque Flux linkage coils
Peak torque[Nm] 12.24
Spring constant[Nm/rad] 77.29
Magnet Flux[Wbp-p] 0.502
The device can utilize the Cogging torque as the spring constant
19
Problem of the proposed device
In the stable point, the proposed device can not output
20
In the unstable point
In the stable point
21Contents
◎Introduction
◎Simulation on drive train components・Frequency characteristics・Decision of the engine speed range harvesting
◎Proposal of the power generation device
◎Power generation simulation of the simple model・Operating theory・Investigation of the effectiveness of the proposed device
◎Conclusion
Power generation simulation
Moment of inertia of the engine [kgm2] I1=0.14
Moment of inertia of the generation device [kgm2] I2=0.013
Synthetic inertia [kgm2] 1
𝐼=
1
𝐼1+
1
𝐼2
Spring constant [Nm/rad] Km=105
Viscosity coefficient [Nms/rad] D=K/1000
Coil resistance [W] R=1.04
The frequency of the excitation force is 15HzThe amplitude of the excitation force is 2Nm, the offset is 5Nm
Excitation force (15Hz)
22
T
1I 2I
1 2
genT
(Generation device)(Engine)
Operating theory
gen2111 TDTI
gen2122 TDI
motion equations
0b KiLRi
Circuit equation
cgen TTT i
electromagnetic torque
※Ti: current torque,Tc: cogging torque
※L: Inductance,Kb: back EMF constant
T
1I 2I
1 2
genT
23
21 ,
Mathematical model of simulations
Simulation of the power generation due to torsional vibrations
θ1,2 i
𝑇𝑖,𝑇𝐶θ1,2T
1I 1I
1I 2I
2I
24
Motion equations Circuit equation
・Induced voltage
・Inductance
Magnetic equation
Electromagnetic Torque
・Current torque
・Cogging torque
Result of simulations
Voltage and Current
・The proposed device can convert the energy of torsional vibrations to magnetic energy and output as electric energy
・The amount of power generation is small
25
Amount of power generation
Adjusting the phase 26
・The phase difference is about 90 degrees・The amount of power generation decreases
tan𝜓 = −𝜔𝐿
𝑅∝ 𝑁
𝜓:the phase angle𝜔:frequency of vibration
𝐿:Inductance𝑅:Coil resistance(1.04W)
𝑁:the number of coils
Inductance
wL
R実軸
虚軸
Y
𝜓 ≒ 84
The amount of power generation increases by adjusting the phase
27Contents
◎Introduction
◎Simulation on drive train components・Frequency characteristics・Decision of the engine speed range harvesting
◎Proposal of the power generation device
◎Power generation simulation of the simple model・Operating theory・Investigation of the effectiveness of the proposed device
◎Conclusion
28Summary
◎Simulation on drive train components・Frequency characteristics➡It is effective to harvest energy utilizing a mechanical resonance
・Decision of the engine speed range harvesting➡The harvested energy increases and the amount of generation
power increases by harvesting in the lower engine speed
◎Proposal of the power generation device
◎Power generation simulation of the simple model・Investigation of the effectiveness of the proposed device➡The proposed device can convert the energy of torsional vibrations
to magnetic energy and output as electric energy➡The amount of power generation increases by adjusting the phase