Design and Development of Energy Harvesting system based on Piezoelectric materials

Project Title

Design and Development of Energy Harvesting system based on Piezoelectric materials

Project Area of Specialization Wearables and ImplantableProject Summary

From the past, there has been an escalation of research in the field of energy harvesting system which is the process used to extract useful energy from the renewable sources available in the ambient environment. Piezoelectric materials are widely used in energy harvesting process to generate the electrical energy in response to ambient mechanical vibration. Additionally, Wind energy is considered to be the most prominent green source to solve the energy crisis and environmental pollution. Therefore, in this research project , hybridization device based on wind source and piezoelectric technique is designed and developed. Analytical modeling is developed and improved by including the influence of the width of a piezo material on output response of the energy harvester. Furthermore, a new technique to develop the mathematical model of energy harvester on the LabVIEW is introduced. Solid works 2016 is used to design this hybridization device. In this device, a concept of lever mechanism is presented being used to magnify the generated force in order to obtain polarization of piezo materials. So, Finite element analysis(FEA) of lever mechanism is done on solid works to obtain bearable values for stress, strain and displacement due to the application of a particular load. Moreover, energy harvesting system based on piezo-material does not depend only on the vibration’s level but greatly depends on the parametric values used in the transition system. Therefore, in this research work, transition system consists of an ideal mass, spring and damper is designed and developed. The Routh-Hurwitz criterion(R-H) is applied to check the stability of transition system. Model is also designed on MATLAB Simscape ToolboxTM  to obtain root-locus and step-response plots for the validation of stability analysis. The results reveal that the system is under-damped and reasonably stable. MATLAB Simscape Toolbox TM  is also used to design the energy harvesting system based on the piezoelectric-stack made-up of Lead Zirconate Titanate. From literature review, its observed that most of the researchers have shown quite linear relation-ships between applied force and voltage. Therefore, certain parametric equations are involved to contemplate the output response of energy harvester with stiffness and damping co-efficient. Optimization is also performed to obtain desired results under given experimental conditions. In energy scavenging system, traditional methods for selection of input parameters do not provide adequate or desired results. Therefore, statistical analysis based on Taguchi and ANOVA approaches are implemented to obtain the optimum output response from the energy harvester.

Project Objectives

The fundamental aim of this project is to build a system that can generate power from energy which used to get wasted in the past. This system when applied on a larger scale can generate a very high amount of power leading to the up scaling of civilization. This objective is accomplished by designing and developing a prototype of energy harvester based on low cost piezoelectric materials. The main objectives of this research project are:

• Design and development of the Horizontal Wind-Piezo scavenging device.
• Implementation of Finite element analysis for lever mechanism on Solid works to attain Stress, strain and displacement curves at a particular load.
• Simulation and analysis of the Energy Scavenging system by MATLAB Simscape ToolboxTM    to obtain generated voltage for various controllable parameters.
• To implement the mathematical modeling of;
  • Wind-based energy harvesting system by using differentiable parameters.
  • Piezo-based cantilever beam by statistically determinate structures.

• Statistical analysis by Taguchi and Anova approaches in order to obtain the voltage optimization of Piezo-scavenging system designed on MATLAB.
• To compare the experimental value with the theoretical as well as numerical value for checking the validity of the system.

Moreover, Figure 1 shows the detailed description of the tasks to accomplish above mentioned objectives.

  Project Implementation Method

This section is divided into following points:

1. Transition system based on Routh-Hurwitz criterion

Transition system consists of a mass which is analogous to inertia, a spring with appropriate stiffness and a damping element creating friction effects as shown in Figure 2.

Its inherently used to transform the mechanical vibration from some kind of industrial machine to piezo harvester. Therefore, Routh-Hurwitz criterion is used to check the stability of the system as given in Table 1.

In order to verify the results of theoretical analysis, MATLAB toolbox Simscape is used to obtain time response and root-locus plots of the system as shown in Figure 3. Results reveal that system in under damped and reasonably stable.

2. Design of energy scavenging system

The commercially available software MATLAB Simscape ToolboxTM  is also used to design the energy harvesting system based on the piezoelectric-stack made-up of Lead Zirconate Titanate. The main components of the design are PZT-stack itself, configuration parameters,  bridge rectifier with filter capacitor and resistive load as shown in the Figure 4.

The equivalent energy scavenging system can be observed from Figure 5.The proposed model has been used to observe the effect of controllable parameters such as force, damping element, stiffness, resistive load on the rectified output voltage.

3. Design of hybridization device on solid works

Solid works 2016 is used to design the model of energy harvester based on the wind-energy and piezo electric technique as shown in the Figure 6.

                                     *Detailed Information regarding this hybridization device is furnished in the technical details*  

4. Finite Element Analysis(FEA)

In the hybridization device, lever mechanism plays a vital role to magnify the spring force which is used to create alternative distributions on the piezo bars. So Solid works is used to analyze the results of finite element analysis  to obtain limiting values for stress stain and relative displacement as shown in Figure 7.

5. Statistical Analysis based on Taguchi design of experiment and Anova Approach

The Taguchi method is a standardize statistical approach to obtain optimum output with the best combination of inputs. This is accomplished through partial factorial design of experiments. Although DOE was originally introduced for robust quality control in manufacturing industries. This method has significance importance in the diverse filed of research and engineering.  Results of this Taguchi method are based on the signal to noise ratio and mean plots as shown in Figure 8. In order to support the results of Taguchi analysis we have performed analysis of variance which comes under the Taguchi Grey. ANOVA test is used to determine the individual contribution of an input parameters for the output response. The present ANOVA is designed with the confidence interval of 95% having the significance level of 5%.

Benefits of the Project

1. In today’s era, energy is the part and parcel for the life of human beings to survive in this mighty world. In order to accomplish that energy, different techniques of energy generation are on the way up. But unluckily, these methods are relatively costly, space expanding, material devouring and above all perilous to the atmosphere.
2. Therefore, until now there was a vacuum for alternative ef?cient energy source that must be the ecofriendly. But nature blessing is the gift that actually cultivates appreciation and the gratitude. So here comes the importance of the piezoelectric materials that actually have the capability to generate the power system which could be a good alternative for fossil fuels etc.
3. It is clean, nonhazardous, easy implementable, inexpensive and ecofriendly source of energy. And the device we have designed and developed is capable to extract that energy which is useless and based on those ambient vibrations electrical energy could be attained.
4. Moreover, with the recent advancement in wireless technology and self-powered electronics, most of the applications now require having the sensor-nodes for a longtime. Normally, power supply is the conventional battery, however due to their lifetime, problems can be encountered while using the batteries. The replacement of batteries is an endless task and can generate problems as the electronics could die at any time .So, an alternative renewable energy source must be needed to obtain the electrical field by using natural resources. Based on these requirements, its highly recommended to use this device in windy areas where wind energy could be utilized to develop small kind of power storage system used as an alternative for a battery.

Technical Details of Final Deliverable

The block diagram for proposed design of energy harvester is shown in the Figure 9. It’s based on a hybridization device consists of a wind machine having three blades with a mutual radius ‘r’. This machine is actually used to extract the kinetic energy from wind-source present in the ambient environment. Output of the device contains a shaft whose diameter is set by considering the shear strength of the material. In this way rotational motion is attained and the shaft is further connected to the wheel of scotch yoke mechanism to accomplish the linear motion. Scotch yoke mechanism actually consists of a slotted rod and a cylindrical slider to make sure that the predefined motion is only in the direction perpendicular to the axis of the shaft .Maximum linear distance covered due to the scotch yoke mechanism depends upon circumference of wheel(C) and can be depicted from Eq.(1).

                                   Linear distance= Number of rotations ×C                         (1)

As observable from Figure 9, rod of scotch yoke mechanism is further connected to spring to obtain generated force. But spring force is not sufficient to produce the alternative distributions on the piezo-beam so lever mechanism with particular young’s modulus (EB) is used to magnify the desired spring force. Hence, equivalent force being applied on the piezo material(Fp) is highly dependent on magnifying ratio(?), relative displacement and the damping force as given in Eq.( 2).

 

Due to application of alternative load on piezo material, polarization effect is influenced and charges are separated so voltage will be generated given in Eqs.(3) and (4).

                                                 

Utilization of research results

• Comparison between analytical and literature results has been developed as shown in the Figure 10. It reveals that generated force will be increased with the variation in the stiffness of the spring.
• Similarly, its contemplated from Figure 11 both stiffness and electrical power are directly proportional to each other.
• Scatter diagrams are used to observe the linear relationship between stiffness and the output voltage as shown in the Figure 12.
• The graphical representations are designed on statistical software NCSS 12 to observe the cumulative effect of all the controllable factors on output voltage and power as shown in Figure 13.

Final Deliverable of the Project HW/SW integrated systemType of Industry Energy Technologies Wearables and ImplantablesSustainable Development Goals Affordable and Clean Energy, Industry, Innovation and InfrastructureRequired Resources

Elapsed time since start of the project	Milestone	Deliverable
Month 1	Design of transition system on Matlab	Design of transition system on Matlab
Month 2	Stability analysis of transition system	Stability analysis of transition system
Month 3	Control parameters for Matlab Simscape Toolbox	Control parameters for Matlab Simscape Toolbox
Month 4	Statistical analysis based on Taguchi and ANOVA approach	Statistical analysis based on Taguchi and ANOVA approach
Month 5	Design of hybridization device on solid works 2016	Design of hybridization device on solid works 2016
Month 6	Implementation of finite element analysis for lever mechanism	Implementation of finite element analysis for lever mechanism
Month 7	Development of wind based piezoelectric energy harvester	Development of wind based piezoelectric energy harvester
Month 8	Analytical model for wind based energy harvester	Analytical model for wind based energy harvester
Month 9	Comparison between analytical and literature results	Comparison between analytical and literature results