Power converters design and analysis for high power piezoelectric ultrasonic transducers

Ghasemi, Negareh; Zare, Firuz

doi:10.1109/epe.2014.6910986

Cited by 7 publications

(5 citation statements)

References 23 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Figure 4 shows the variation of f o of the system with increasing l c from 0 mm to 22 mm. The drop in the f o from the f i correlates with research work in which resonance frequency is found to be the lowest frequency within the impedance curve [36]. The output power of the system gradually increases with l c due to its approach near resonance frequency, which allows efficient transmission of the ultrasonic power to the material.…”

Section: Resultssupporting

confidence: 56%

Utilization of ultrasonically forced pulsating water jet decaying for bone cement removal

Nag

Hloch

Dixit

et al. 2020

Int J Adv Manuf Technol

View full text Add to dashboard Cite

Ultrasonic pulsating water jet for non-thermal and selective removal of acrylic bone cement is studied. Variation of acoustic chamber length is used for tuning of the ultrasonic system into the resonance regime to gain maximum power transmission. The study investigates the minimal technological conditions such as nozzle traverse speed and supply water pressure required to generate disintegration grooves in bone cement mantle. It also proposes the safe standoff distance range, which is essential for its potential application during the extraction of bone cement without compromising host bone. Palacos R+G bone cement was used for the experiments. Generated groove depths were measured using MicroProf FRT and analyzed using SPIP software. Depth values showed an increasing trend with an increase in acoustic chamber length, decrease in traverse speed, and increase in supply pressure values. From the entire experimental domain, a maximum depth of 615 μm was obtained at 22-mm chamber length, 0.5mm/s traverse speed, 10-MPa pressure, and a standoff distance of 4 mm. Brittle fractured surface features like material chipping, micro-pits, cracks, and sheared material layers were observed in the SEM images. Disintegrated debris, diameter 21-37 μm, conceived from pit diameters can be used to design a suction unit. Real-time control of the disintegration process using accelerometer sensors was shown. The results support the idea of using pulsating water jet for bone cement removal in a single blind hole. Minimal technological parameters reduce reaction force of the hand tool, allowing bone cement removal without bone fracture or perforation.

show abstract

Section: Resultssupporting

confidence: 56%

Utilization of ultrasonically forced pulsating water jet decaying for bone cement removal

Nag

Hloch

Dixit

et al. 2020

Int J Adv Manuf Technol

View full text Add to dashboard Cite

show abstract

“…However, the resonant frequency of the transducer can be easily changed during its operation due to environmental and structural changes. The effect of the transducer resonant frequency changes on its energy conversion performance was thoroughly studied in (Ghasemi, 2012;Ghasemi et al, 2012;Davari et al, 2014) and it was shown that the transducer performance is degraded with the change of its resonant frequency. Therefore, detecting the resonant frequency of the transducer and adjusting the operating frequency of the system during the real-time operation is necessary for efficient energy conversion.…”

Section: Treatment Methodsmentioning

confidence: 99%

“…Therefore, detecting the resonant frequency of the transducer and adjusting the operating frequency of the system during the real-time operation is necessary for efficient energy conversion. To address this issue, an online algorithm was developed in (Davari et al, 2014) to measure the main resonant frequency of the transducer during the real-time operation. Any change in the main resonant frequency of the transducer can be detected using this algorithm.…”

Section: Treatment Methodsmentioning

confidence: 99%

“…Once any variation in the resonant frequency was detected, the operating frequency can be adjusted accordingly to achieve the efficient energy conversion performance of the transducer and deliver the maximum power to the water solution. These issues can be addressed by developing smart power electronics converters to generate excitation signals with adjustable power and frequency (Ghasemi, 2012;Davari et al, 2014). Figure 1 shows a power converter and its control algorithm that can be developed for a dual-mode ultrasound system.…”

Section: Treatment Methodsmentioning

confidence: 99%

See 1 more Smart Citation

Removal of polycyclic aromatic hydrocarbons from wastewater using dual‐mode ultrasound system

Ghasemi

Gbeddy

Egodawatta

et al. 2019

Water & Environment J

Self Cite

View full text Add to dashboard Cite

Treatment of wastewater using ultrasound systems is gaining increasing interest due to its effectiveness for a wide range of pollutants and no secondary pollutant production. This paper proposes two ultrasound systems operating at different ranges of electrical power and frequency developed to remove toxic polycyclic aromatic hydrocarbon (PAH) compounds in wastewater. Both light molecular weight (LMW) and high molecular weight (HMW) compounds were degraded using the developed systems. However, HMW compounds were more affected. The experimental results revealed that treatment at a high power level is not always a proper approach for a large reduction of PAH compounds. Whereas treatment at higher frequencies and lower power can be a suitable alternative to enhance the PAHs removal rate and the system energy efficiency and reduce losses. Therefore, a dual-mode ultrasound system with adjustable operating frequency and power is a promising approach for the treatment of industrial wastewater containing toxic PAH compounds.

show abstract

“…The resonance frequency is found by plotting the impedance frequency response (Fig. 4.6) [100]. The resonance occurs when the impedance of the piezoelectric element is at its lowest.…”

Section: Mathematical Formulationmentioning

confidence: 99%

Stent with Piezoelectric Transducers for High Spatial Resolution Ultrasound Neuromodulation- a Finite Element Analysis

Dilevicius

Serdijn

Costa

2022

2022 44th Annual International Conference of the IEEE Engineering in Medicine &Amp; Biology Society (EMBC)

View full text Add to dashboard Cite

D EEP brain stimulation is currently the only technique used in the clinical setting, capable of stimulating the deep brain nuclei. Recently, low intensity focused ultrasound has been shown to reversibly modulate brain activity. At present, ultrasound neuromodulation is performed through the transcranial pathway. This requires the ultrasound waves to pass through the skull, thus attenuating the ultrasound waves. To reduce the effect of attenuation, lower frequencies are used of around 0.5 M H z, however, with decreasing frequency the focal region in which the stimulation occurs also increases. Therefore, a stent with an array of ultrasound transducers operating at high frequencies of around 5 M H z has been proposed to bypass the skull, thus significantly reducing the attenuation. Moreover, such a device would require a minimally invasive procedure removing the need for open brain surgery as currently performed for deep brain stimulation. This research was performed to evaluate the feasibility of using ultrasound arrays within the brain vasculature to stimulate deep brain nuclei using the finite element method.Initially, a literature review was conducted to identify the optimal ultrasound parameters for achieving neuromodulation. For stimulation, a PRF ranging from 500 to 1500 H z and a DC of around 50 to 70% were found to be optimal. Whereas for suppression, a PRF of<100 H z and a DC of around >=10% were found to be ideal. The intensity for both suppression and stimulation was found to greatly depends on the target region and individual as well as anaesthesia for stimulation, nonetheless, for 5 M H z an intensity of around 1 W /cm 2 was required to achieve neural excitation.Next, the brain nuclei were studied and the subthalamic nucleus, ventral intermediate nucleus and globus pallidus internus were identified to be the most commonly targeted nuclei for deep brain stimulation. Brain vasculature was then examined in terms of the blood vessel inner diameter, shape, orientation with respect to the nuclei and the distance to the nuclei. Basal vein of Rosenthal, internal cerebral vein and internal carotid artery were found to be most suitable to target the subthalamic nucleus, ventral intermediate nucleus and globus pallidus internus respectively.Afterwards, two-dimensional simulations were performed using COMSOL Multiphysics to identify the minimum required array width and length for stimulating each nucleus from its respective blood vessel. However, when compared to 3D counterparts it was found that 2D significantly overestimated the size of the focal region.Finally, 3D simulations of 100 x 100 x 262 µm transducers in a 104 (2D 26 x 4) and 105 (Checkered [3 x 2] x 21) arrays within the BVR were analysed targeting the STN. These arrays were found to produce a focal region of full width half intensity within the subthalamic nucleus model boundaries while reaching intensities and pressures of 0.558 W /cm 2 or 0.140 MPa and 0.311 W /cm 2 or 0.101 M P a with a 1 V terminal for 2D and checkered array respectively. Theref...

show abstract

Power converters design and analysis for high power piezoelectric ultrasonic transducers

Cited by 7 publications

References 23 publications

Utilization of ultrasonically forced pulsating water jet decaying for bone cement removal

Utilization of ultrasonically forced pulsating water jet decaying for bone cement removal

Removal of polycyclic aromatic hydrocarbons from wastewater using dual‐mode ultrasound system

Stent with Piezoelectric Transducers for High Spatial Resolution Ultrasound Neuromodulation- a Finite Element Analysis

Contact Info

Product

Resources

About