Name: ac circuit node method in an angioplasty model
Uploaded: 2024-04-11T12:48:49.000Z
Duration: 1 min 14 s
Channel: JoVE

In the rotablator angioplasty system, the turbine causes the rotation of the catheter burr, which aids in removing plaque deposits from coronary arteries.
The operational and control circuit of this system can be modeled as a dual-node RLC circuit with a current-controlled current source.
When the input source voltage, inductance, and capacitance values are known, the shaft&#39;s driving voltage can be calculated using nodal analysis.
By utilizing the angular frequency, inductance, and capacitance values, the impedance across the inductor and capacitor is computed, and a corresponding frequency domain circuit is drawn.
Applying Kirchhoff&#39;s current law and Ohm&#39;s law at the first node, and substituting the expression for the source current gives a simplified equation.
Similarly, applying Kirchhoff&#39;s current law and Ohm&#39;s law at the second node results in another equation. Substituting the first nodal equation and simplifying the equation further, gives the voltage at node one which is equal to the source voltage.
Finally, the shaft voltage is transformed into the time domain.

node analysis for ac circuits

Consider an angioplasty system featuring a catheter equipped with a turbine, a critical tool for removing plaque deposits from coronary arteries. This intricate medical device operates using a circuit model reminiscent of a dual-node RLC circuit powered by a current-controlled voltage source.
To unravel the complexities of this system, nodal analysis is employed, a powerful technique founded on Kirchhoff's current law (KCL), which remains valid for phasors. AC circuits can effectively be analyzed using nodal analysis.
The process begins with gathering information about the input source voltage, inductance, and capacitance values. These data points can calculate the driving voltage for the catheter's shaft. Leveraging angular frequency, inductance, and capacitance values, the impedance across the inductor and capacitor is determined, mapping out a frequency domain circuit.
<img alt="Electrical impedance formula \(Z_L = j\omega L\); equation for inductive reactance." src="/files/ftp_upload/15110/15110_PT_Equation_1.svg" style="text-align: center; height: 16px;" data-altupdatedat="1762173717000" data-alt="Equation1" />
<img alt="Capacitive reactance formula \(Z_c = \frac{1}{j\omega C}\). Electrical circuit analysis." src="/files/ftp_upload/15110/15110_PT_Equation_2.svg" style="text-align: center; height: 40px;" data-altupdatedat="1762173717000" data-alt="Equation2" />
KCL and Ohm's law are applied at both nodes, yielding equations that describe the system's behavior. When simplified and integrated, these equations reveal that the shaft voltage precisely equals the source voltage.
This comprehensive analysis provides essential insights into the electrical operation of the angioplasty system. The voltage data can then be converted into the time domain, allowing for assessing and optimizing the system's performance for effective plaque removal in medical procedures.

Node Analysis for AC Circuits

In the rotablator angioplasty system, the turbine causes the rotation of the catheter burr, which aids in removing plaque deposits from coronary 
...

Education

JoVE Core

Electrical Engineering

Unit 1

AC Circuit Analysis

KEY TERMS AND CONCEPTS

ac circuit node method in an angioplasty model

AC circuit node analysis is used to study an angioplasty system with a catheter turbine. The system helps remove plaque deposits from coronary arteries. Its electrical model is similar to a dual-node RLC circuit driven by a current-controlled voltage source.

The analysis begins by collecting the input source voltage, inductance, and capacitance values. These measurements are used to find the driving voltage for the catheter shaft. The circuit is then viewed in the frequency domain, where angular frequency helps determine the impedance of the inductor and capacitor.

Kirchhoff's current law, or KCL, is applied at both nodes. Ohm's law is also used to write the node equations. Because KCL remains valid for phasors, the AC circuit can be analyzed with nodal analysis in a clear and organized way.

After the equations are simplified and combined, the result shows that the shaft voltage equals the source voltage. The voltage can then be converted back into the time domain. This helps assess and optimize the system's performance for effective plaque removal in medical procedures.

AC Circuit Node Method in an Angioplasty Model

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Learn how nodal analysis and KCL are used to model an angioplasty catheter turbine as a dual-node RLC AC circuit and determine shaft voltage.

AC Circuit Node Method in an Angioplasty Model | JoVE K12

JoVE Core Electrical Engineering offers easy-to-understand animated videos that cover fundamental concepts of electric circuits along with circuit analysis techniques. It incorporates first-order and second-order circuits using operational amplifiers and circuit transformation concepts. The inclusion of practical design examples and real-world applications through scientist-in-action videos adds significant educational value, making complex concepts accessible.

electrical engineering

AC Circuit Node Method in an Angioplasty Model

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