EMWorks Newsletter 2019



Simulation of wireless power transfer system for pacemaker application

Wireless energy transfer or wireless power is the transmission of electrical energy from a power source to an electrical load without interconnecting wires. Wireless power transfer (WPT) is used in medicine for implanted and wearable medical devices in human body such as pacemaker.

The traditional pacemakers must be replaced periodically by surgery due to their non-rechargeable batteries. The use of pacemakers with rechargeable batteries increased after it was abandoned before. An external coil transmits power to a receiver coil implanted under the skin. The receiver coil will provide energy for the pacemaker battery. Rechargeable battery pacemaker can offer several advantages like increasing the lifetime and reliability of pacemakers, reducing the maintenance surgeries which can cause medical complications (bleeding, infection), a flexible external control of the pacemaker, etc..

The proposed model is shown in Figure 1. The WPT system is composed of two coils made of coppers and shielding components. The shielding components are made of two aluminum plates and two iron cores. Figures 2 and 3 show respectively the magnetic flux distribution -without and with- shielding components.

The magnetic flux is symmetric around the transmitter in the case of the model without shielding components while it is directed toward the receiver in the second case. The shielding components helps to increase the efficiency of the WPT system. Table 1 resumes the circuit parameters of WPT system computed by EMS. To maximize the efficiency of this system, two parallel resonant capacitances are inserted in the circuit. Figure 4 shows the circuit schematic of the inductive coupling charger modeled using EMS circuit tool. Figure 5 shows the induced current in the receiver coil versus frequency. It reaches its peak value at the resonance.

Figure 1 - 3D model of WPT system

Figure 2 - Magnetic flux distribution in case of model without shielding component

Figure 3 - Magnetic flux distribution in case of model with shielding component

Table 1 - Comparison of the WPT circuit parameters

Figure 4 - Equivalent circuit of WPT charge

Figure 5 - Receiver versus frequence


The pacemaker that doesn't need a battery: Implant can be placed directly into the heart and be charged wirelessly

A battery-less, wireless pacemaker than can be directly implanted into a patient's heart has been developed by researchers. Normally, pacemakers aren't directly implanted, but instead are located away from the heart where surgeons can periodically replace their batteries with minor surgery.

But the newly developed pacemaker, which is smaller than dime, can harvest energy wirelessly via an external battery pack - eliminating the need for surgeries to replace the battery, and making it far more effective.


Wireless 'pacemaker for the brain' could offer new treatment for neurological disorders

Device fine-tunes treatment by stimulating and recording electric current in the brain at the same time

In a proposed device, two of the new chips would be embedded in a chassis located outside the head. Each chip could monitor electrical activity from 64 electrodes located into the brain while simultaneously delivering electrical stimulation to prevent unwanted seizures or tremors. Credit: Rikky Muller, UC Berkeley



EMS comes with an integrated linear static structural solver. EMS allows users to couple Electromagnetics with linear static stress. Electromagnetic phenomenon can apply forces to different parts then the structural coupling calculates the stress, the strain and the displacement due to these forces.

Deformation and thermal stress can also be computed and visualized through the Structural/Thermal coupling. Deformation can be caused by electromagnetic forces and temperature rise resulting from Joule heating, eddy current and core loss. All coupling is carried out in the same analysis study and on one same original model geometry and mesh. No export/import of data is required for the coupling. Non-electromagnetic loads and conditions can also be added to the coupling analysis in the form of mechanical force, moment, pressure, gravity, temperature, spring, tie constraint and rigid constraint.

Read more about stuctural coupling

Find out electro-stuctural applications

Find out magneto-stuctural applications



Analysis of a Highly Nonlinear Lorentz Force Linear Motion Electromagnetic Actuator Using EMS
Ian Hunter, Ph.D. and Serge Lafontaine, Ph.D Massachusetts, USA

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APEC 2019



March 17-21, 2019, Anaheim, California , Booth #1163

May 21-23, 2019, Messe Berlin, Booth Hall 1_2, Stand C53