Download Laboratory Experiment 11 on The Power Triangle | ELEC 195 and more Lab Reports Microelectronic Circuits in PDF only on Docsity! Wentworth Institute of Technology Name: Department of Electronics and Mechanical Date: ELEC 195 - Circuits Theory II Experiment 11 The Power Triangle Objective: 1. Calculate the real, apparent, and reactive power in a circuit. 2. Learn how to utilize a voltmeter and a sensing resistor to make these calculations. Equipment Required: Resistors: 100 Capacitor: 1 F Leads (2) BNC to alligator clips, 1 set banana to alligator clips Jumpers A breadboard Resume of Theory: Impedance in the frequency domain is the quantity analogous to resistance, inductance and capacitance in time domain. The imaginary part of the impedance is called reactance. The reactance of an inductor or capacitor is a function of the applied frequency as defined by the followings 1 CX C LX L where f 2 rad/s , L =the inductance (H) and C = the capacitance (F) The inductor and capacitor impedances: rectangular: polar Zc = j Xc ZL = |XL|90o ZL = j XL Zc = |Xc|-90o The calculation of the impedances assist you in determining the values for the power consumed by each device. In order to make the calculations, you need to determine the power factor. This requires you to know the phase relationship between the voltage and the current in the circuit. A sensing resistor is use to determine the magnitude of the current. The phase of the current is derived from the impedance by calculation, then the power factor can be determined. Once you have this information along with the voltage and current magnitudes you can determine the power triangle. The power relationships are defined thusly: Designation Name Units of measurement Formula Notes S Apparent power Volt-amps, VA S=V*I S=V*I* is polar form of power. I* is conjugate of I P Real (average) power Watts, W P= V*I cos Ф Ф = power factor Q Reactive power Volt amps reactive, VAR Q= V*I sin Ф Power factor =P/S & phase difference ‘twn V and I. In this lab you built a circuit and compare the theoretical values to actual measurements. You will determine the volts delivered and the current consumed noting their phase difference. From this information you construct a Power Triangle. Procedure: PART I: Capacitive Load a) Construct the circuit shown below (Fig 4.1) Fig. 4.1 b) Measure the sensing resistor Rs = ______________ c) Measure the RMS value of VRs VRs = ______________ d) Calculate Irms Irms=________________
