6.9:
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 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'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's current law and Ohm's law at the first node, and substituting the expression for the source current gives a simplified equation.
Similarly, applying Kirchhoff's current law and Ohm'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.
6.9:
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.
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.