DSPIC33FJ128GP706A-E/MR Microchip Technology, DSPIC33FJ128GP706A-E/MR Datasheet - Page 94

• Manufacturer Part Number: DSPIC33FJ128GP706A-E/MR
• Description: 16 Bit MCU/DSP 40MIPS 128KB FLASH 64 QFN 9x9x0.9mm TUBE
• Manufacturer: Microchip Technology
• Series: dsPIC™ 33Fr

Specifications of DSPIC33FJ128GP706A-E/MR

• Core Processor: dsPIC
• Core Size: 16-Bit
• Speed: 40 MIPs
• Connectivity: CAN, I²C, IrDA, LIN, SPI, UART/USART
• Peripherals: AC'97, Brown-out Detect/Reset, DMA, I²S, POR, PWM, WDT
• Number Of I /o: 53
• Program Memory Size: 128KB (128K x 8)
• Program Memory Type: FLASH
• Ram Size: 16K x 8
• Voltage - Supply (vcc/vdd): 3 V ~ 3.6 V
• Data Converters: A/D 18x10b/12b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 125°C
• Package / Case: 64-VFQFN, Exposed Pad
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

MCP3909 / dsPIC33F 3-Phase Energy Meter Reference Design
C.12 HARMONIC COMPONENTS OF CURRENT, VOLTAGE AND TOTAL
DS51723A-page 94
HARMONIC DISTORTION
In Section C.3 “The Harmonic Analysis Algorithm Of Quasi-synchronous Sam-
pling”, we discussed the measuring of current and voltage signals for each order of
harmonics. 3 parameters are used to show to what extent a distorted wave deviates
from a sine wave. They are: harmonic content, total distortion and harmonic ratio of the
k-th harmonic. The term harmonic content means the root of square of effective values
for all harmonics, which is defined as:
EQUATION C-60:
The total voltage distortion ratio of harmonics is the ratio of harmonic content to the
fundamental in percentage, which is defined as:
EQUATION C-61:
The k-th harmonic ratio for voltage is the ratio of the k-th harmonic to the fundamental
in percentage, defined as:
EQUATION C-62:
Similarly, harmonics of each order for the current and total distortion ratio can be sorted
out.
THD
U
=
THD
U
-------
U
U
H
H
I
Uk
×
=
100%
=
k
U
------
U
∑
N
=
1
k
2
×
k
U
∑
100%
N
=
k
2
2
(
THD
Uk
)
© 2009 Microchip Technology Inc.
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