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

在旋磨血管成形术系统中，涡轮驱动导管磨头旋转，有助于清除冠状动脉中的斑块沉积物。
该系统的操作与控制电路可建模为一个具有电流控制电流源的双节点 RLC 电路。
当已知输入源电压、电感和电容值时，可使用节点分析法计算轴的驱动电压。
利用角频率、电感和电容值，计算电感器和电容器上的阻抗，并绘制相应的频域电路图。
在第一个节点应用基尔霍夫电流定律和欧姆定律，并代入源电流的表达式，可得到一个简化方程。
同理，在第二个节点应用基尔霍夫电流定律和欧姆定律可得到另一个方程。将第一个节点方程代入并进一步简化该方程，可得节点一的电压，其值等于电源电压。
最后，将轴电压转换到时域。

交流电路的节点分析

假设要采用一个配备涡轮机导管的血管成形术系统，涡轮机是去除冠状动脉斑块沉积物的关键工具。这种复杂的医疗设备所使用的电路模型能够让人们想起由电流控制电压源供电的双节点 RLC 电路。 为了能够揭示该系统的复杂性，从而采用了节点分析，这是一种基于基尔霍夫电流定律 (KCL) 的强大技术，该定律对于相量是仍然有效的。使用节点分析可以有效地对交流电路进行分析。 该过程会首先收集有关输入源的电压、电感和电容值的信息。这些数据点可以计算出导管轴的驱动电压。从而利用角频率、电感和电容值来确定电感器和电容器两端的阻抗，从而绘制出频域电路。 <img alt="Equation1" src="/files/ftp_upload/15110/15110_PT_Equation_1.svg" style="text-align: center; height: 16px;"> <img alt="Equation2" src="/files/ftp_upload/15110/15110_PT_Equation_2.svg" style="text-align: center; height: 40px;"> 基尔霍夫电流定律和欧姆定律应用于两个节点处，从而能够得出描述系统行为的方程。经过简化和积分后，这些方程能够表明轴电压会精确的等于源电压。 这种全面的分析为血管成形术系统的电气操作提供了重要的见解。同时可以将电压的数据转换为时域，以此来评估和优化系统的性能，同时使其在医疗领域中能够有效的去除牙菌斑。

在旋磨血管成形术系统中，涡轮驱动导管磨头旋转，有助于清除冠状动脉内的斑块沉积物

Education

教育

JoVE Core

Electrical Engineering

电气工程

Unit 1

第一单元

AC Circuit Analysis

交流电路分析

KEY TERMS AND CONCEPTS

关键术语与概念

Node Analysis for AC Circuits

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

ac-circuit-node-method-in-an-angioplasty-model

sinusoidal sources

AC Waveform Basics and Phase

Alternating current, or AC, changes direction and magnitude over time, unlike direct current, or DC, which flows in one direction with constant polarity. AC is the main form of electricity used for modern power transmission and distribution because it can travel long distances efficiently. In homes, power supplies use sinusoidal sources to deliver electricity. A sinusoidal source creates a voltage that rises and falls in a smooth wave-like pattern. This waveform is called a sinusoid, which is...

graphical and analytic representation of sinusoids

graphical-and-analytic-representation-of-sinusoids

Measuring Sinusoid Phase on an Oscilloscope

Measuring sinusoid phase on an oscilloscope helps compare two sinusoidal voltages with the same amplitude and period. An oscilloscope is an instrument used to display and analyze waveforms. The process starts by reading the peak-to-peak value, which is twice the amplitude of the sinusoid. This shows the maximum voltage swing of the waveform. Next, the period and angular frequency are measured. The period is the time for one complete cycle. Angular frequency, often written as omega, is the rate...

phasors

Phasors for AC Circuit Analysis

Phasors are a mathematical tool for analyzing alternating current, or AC, circuits. They represent sinusoids with complex numbers. The phasor magnitude matches the sinusoid amplitude, and the phasor angle shows the phase measured from the positive x-axis. Phasors make AC circuit analysis simpler by removing time from the current and voltage expressions. That lets an AC circuit be treated like its equivalent direct current, or DC, form for calculations. Phasors can also be written in...

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Phasor Rules for AC Circuit Analysis

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phasor relationships for circuit elements

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AC Circuit Phasors: Resistor, Inductor, Capacitor

AC circuit phasors help show how voltage and current behave for resistors, inductors, and capacitors. Phasor representation moves these relationships from the time domain to the frequency domain, which makes AC circuit analysis easier. For a resistor, Ohm's law still applies. The voltage across the resistor and the current through it stay in phase, so their phasors point in the same direction. An inductor works differently because its voltage depends on the rate of change of current. The...

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AC Circuit Rules with Phasor Diagrams

AC circuit analysis uses Kirchhoff's voltage law and Kirchhoff's current law with phasors. In household wiring, AC power from a distribution panel is sent to appliances connected in parallel. These rules help describe how voltage and current behave in sinusoidal steady state. Kirchhoff's voltage law, or KVL, says that the sum of phasor voltages around a closed loop in an AC circuit is zero. The voltages can first be written in the time domain and then changed into phasor form. In phasor...

impedances and admittance

AC Circuit Response: Impedance and Admittance

AC circuit response changes with frequency, and impedance describes how resistors, inductors, and capacitors affect sinusoidal current flow. In phasor form, voltage and current are used to show this behavior in a clear way. Impedance is a key idea in AC circuit analysis because it measures opposition to current in an alternating circuit. These components behave differently in AC than in DC. In DC circuits, inductors act like short circuits and capacitors act like open circuits. In AC circuits,...

impedance combination

Series and Parallel Impedance Rules

Impedance in series and parallel circuits follows the same rules used for resistors. A string of Christmas lights is a simple example. Each bulb represents one impedance element. In a series connection, the current stays the same through every component. This series behavior matches Kirchhoff’s Voltage Law, or KVL. The total impedance in the circuit is the sum of the individual impedances. The source voltage is then divided among the components based on their values. This is the voltage...

node analysis for ac circuits

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...

mesh analysis for ac circuits

Impedance Matching with Mesh Currents

Impedance matching in radio communication uses resistor, capacitor, and inductor circuits to help signals move efficiently between a transmitter and a receiver. The circuit must balance the input and output signals before the current in the capacitor can be found. This makes the problem a good example of AC circuit analysis for high school students. The first step is to identify the input voltage and the output signal. The angular frequency is then taken from the time-domain form of the input...

source transformation for ac circuits

AC Source Conversion in Circuit Analysis

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th&#233venin equivalent circuits

Finding Voltage and Impedance in Circuit A

The household power distribution system can be simplified with Thevenin's theorem. In this system, distribution lines and transformers form the main network. Electrical appliances can be treated as load impedance, which makes the circuit easier to analyze. An AC circuit can be split into two parts, circuit A and circuit B, with a single pair of terminals between them. Circuit A can then be replaced by its Thevenin equivalent circuit. That equivalent has a voltage source in series with an...

norton equivalent circuits

Norton Current in AC Circuit Analysis

Norton’s theorem helps simplify complex AC circuits by replacing a two-terminal linear network with a smaller equivalent circuit. That equivalent circuit uses an impedance in parallel with a constant current source. The method lets students break one complicated circuit into two parts and analyze them more easily. To build the Norton equivalent, the source is replaced by its internal impedance. The result is the Norton impedance, which is the same as the Thévenin impedance. This parallel...

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Analyzing Mixed-Frequency Linear Circuits

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Analyzing an Op Amp Audio Filter

An op amp audio filter shapes an amplified sound signal by strongly reducing the lower-frequency parts. In this circuit, the focus is on a basic filter setup used after an amplifier in an audio system. The filter uses an operational amplifier in an inverting arrangement with resistors R1 and R2 and a capacitor C1. The analysis starts with a known input signal and asks for the output signal. To solve it, the capacitor impedance is found first. That requires the angular frequency from the...

design example: capacitance multiplier circuit

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Capacitance Multiplier Circuit for Larger Capacitance

A capacitance multiplier circuit creates a larger effective capacitance from a small physical capacitor. In integrated circuit technology, this approach is useful when a small capacitor is not enough. The circuit can multiply capacitance by as much as 1000, so a 10-pF capacitor can act like a 100-nF capacitor. The design uses two op-amps. The first op-amp works as a voltage follower, which helps isolate the generated capacitance from the loading caused by the second stage. The second op-amp...

key terms and concepts

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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