Rectifier-with-Capacitor-Filter

Design of a Bridge Rectifier with Capacitor Filter for AC to DC Conversion

Tasks:

Designing the circuit given below:

• Simulate the circuit with idealities and non-idealities.
• Measure the power factor and compare the power factors for both cases.

Specifications:

• Average output Power = 100W
• Input Voltage = 20V rms @50Hz

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Working on the Design

Component Values from matlab/octave:

Values of the components is calculated according to the specification from the simulation of the program click here

Simulation of the Circuit:

The Circuit can be simulated with spice, here I used gEDA for building the cirucuit netlist and then simulated it with the stimulus designed by me. I used the model of the diode too that is included in the netlist file.

• gEDA schematic (.sch) click here
• spice netlist of the circuit (.net) click here
• simulation analysis (.cir) click here
• diode model (.mod) click here

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Final Design and Simulation Results

SPECIFICATIONS FOR THE RECTIFIER 

• Output Power, W = 10.00
• Input voltage, volts = 20.00
• Input voltage tolerance, percent = 20.00
• Peak to peak output ripple, percent = 10.00
• Supply frequency, Hz = 50.00  

CAPACITOR SELECTION

• Capacitor value, uF = 390.56
• Voltage should be >, V = 28.94
• Rms value of current, A = 0.98  

DIODE SELECTION

• PIV, V = 33.94
• Avg. current, A = 0.35
• Rms value of current, A = 0.89

Circuit Schematic without non-idealities:

Input and Output Waveform:

Input Current wrt Voltage Waveform:

Circuit Schematic with non-idealities:

Non-idealities considered are as follows:

• ESR (Effective Series Resistance) of the capacitor is considered.
• Inductive effect of the load is considered. (say 10mH)

Input Current and Voltage Waveform:

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Power Factor Calculations:

Where,

• V_m : Peak Voltage
• I_m : Peak current
• V : Instantaneous Voltage
• I : Instantaneous Current

Reference Power is the power dissipated across a pure resistive load with the value of voltage and current maximum to be V_m and I_m respectively.

Power Factor without non-idealities:

As per the data,

• V_m = 20 V
• I_m = 5.2 A
• V_rms = 16 V
• I_rms = 0.64 A
• Real Power = 10 Watts (Design Basis)
• Reference Power = 52 W
• Power factor = 0.192 (Leading)

Power Factor with non-idealities:

As per the data,

• V_m = 20 V
• I_m = 4.8 A
• V_rms = 15.5 V
• I_rms = 0.645 A
• Real Power = 10 Watts (Design Basis)
• Reference Power = 48 W
• Power factor = 0.208 (Leading)