DSPIC33FJ128GP706-I/PT Microchip Technology, DSPIC33FJ128GP706-I/PT Datasheet
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DSPIC33FJ128GP706-I/PT Summary of contents
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... MCP3909 / dsPIC33FJ128GP206 © 2009 Microchip Technology Inc. 3-Phase Energy Meter Reference Design DS51823A ...
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... REAL ICE, rfLAB, Select Mode, Total Endurance, TSHARC, UniWinDriver, WiperLock and ZENA are trademarks of Microchip Technology Incorporated in the U.S.A. and other countries. SQTP is a service mark of Microchip Technology Incorporated in the U.S.A. All other trademarks mentioned herein are property of their respective companies. ...
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... ReadING A/D Data Of The MCP3909 Device .............................................. 35 3.6 Communication Of UART Interface .............................................................. 37 3.7 Resource Configuration ................................................................................ 37 3.8 Description Of Project Files .......................................................................... 38 Chapter 4. Meter Calibration 4.1 Introduction ................................................................................................... 39 4.2 Current/voltage Calibration .......................................................................... 39 4.3 Apparent Power Calibration ......................................................................... 40 4.4 Phase Lag Calibration ................................................................................. 41 © 2009 Microchip Technology Inc. MCP3909 / dsPIC33F 3-PHASE Table of Contents DS51723A-page 3 ...
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... Sampling Algorithm ........................................................................ 84 C.5 Measuring Frequency .................................................................................. 87 C.6 Improving Measurement Precision Of Quasi-synchronous Sampling Algorithm ................................................................................................................. 89 C.7 Measuring Secondary Parameters .............................................................. 91 C.8 Apparent Power Of Each Phase And Total Apparent Power ....................... 91 C.9 Power Factor Of Each Phase And Total Power Factor ............................... 91 DS51723A-page 4 © 2009 Microchip Technology Inc. ...
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... C.13 Compensation For Ratio Error And Phase Lag ......................................... 95 C.14 Relationship Between Error And Current ................................................... 96 C.15 Ratio Error Compensation ......................................................................... 97 C.16 Phase Lag Compensation ......................................................................... 98 Appendix D. 50/60 Hz Meter Operation D.1 Firmware Versions ..................................................................................... 103 Worldwide Sales and Service .................................................................................. 104 © 2009 Microchip Technology Inc. DS51723A-page 5 ...
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... MCP3909 / dsPIC33F 3-Phase Energy Meter Reference Design NOTES: DS51723A-page 6 © 2009 Microchip Technology Inc. ...
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... Document Layout • Conventions Used in this Guide • Recommended Reading • The Microchip Web Site • Customer Support • Document Revision History © 2009 Microchip Technology Inc. MCP3909 / dsPIC33F 3-PHASE Preface NOTICE TO CUSTOMERS ® IDE on-line help. DS51823A-page 7 ...
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... Appendix C. “Power Calculation Theory” detailed explanation of the theory behind the calculations described in Chapter 3. “Firmware” • Appendix D. “50/60 Hz Meter Operation” - Instructions on converting the meter for use line frequency environment DS51823A-page 8 © 2009 Microchip Technology Inc. ...
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... N‘Rnnnn Text in angle brackets < > Courier New font: Plain Courier New Italic Courier New Square brackets [ ] Curly brackets and pipe character Ellipses... © 2009 Microchip Technology Inc. Represents Referenced books MPLAB Emphasized text ...is the only compiler... A window the Output window A dialog ...
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... Local sales offices are also available to help customers. A listing of sales offices and locations is included in the back of this document. Technical support is available through the web site at: http://support.microchip.com DOCUMENT REVISION HISTORY Revision A (November 2009) • Initial Release of this Document. DS51823A-page 10 © 2009 Microchip Technology Inc. ...
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... Harmonic Component Measurement of Voltage Input: 2 • Harmonic Component Measurement of Current Input: 2 • Creeping: Anti-creeping Design (<0.0008 I • Two Pulse Outputs: Total Phase Active Power, Total Phase Reactive Power • Pulse Constant: 3200 Imp/kWh © 2009 Microchip Technology Inc. MCP3909 / DSPIC33F 3-PHASE ...
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... Phase Missing / Line voltage sag detection and alarm • Total Active Energy: - The Algebraic Sum Of Positive/negative Active Energy • Positive/negative Active Energy • Positive/negative Reactive Energy • Four-quadrant Reactive Energy • Voltage/current Harmonic Content Of Each Phase DS51723A-page 12 © 2009 Microchip Technology Inc. ...
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... See Chapter 4. “Meter Calibration” for more information. All connections described in this section are dependent on the choice of current sensing element and a secondary external transformer may be required in higher current meter designs. © 2009 Microchip Technology Inc. Meter Overview MCP3909 dsPIC33 Current Transformer ...
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... Turn on the power to the energy meter. D1 should be lit showing the meter has power. At this point load is connected and the meter is measuring power, the power LED, D1, should be blinking. DS51723A-page OUT IN OUT Meter Case Bottom. and OUT and given IN OUT OUT © 2009 Microchip Technology Inc. ...
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... Windows™ Operating System, and selecting the proper comm port for RS-232 communication, the following screen should show real-time meter results. The following chapters include more detail on the firmware, calculation, and PC software. . FIGURE 1-3: “PM_Viewer” or Power Meter Viewer PC Software. © 2009 Microchip Technology Inc. Meter Overview DS51723A-page 15 ...
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... MCP3909 / dsPIC33F 3-Phase Energy Meter Reference Design NOTES: DS51723A-page 16 © 2009 Microchip Technology Inc. ...
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... Neutral line CT Phase A PT Phase A CT Phase B PT Phase B CT Phase C PT Phase C CT FIGURE 2-1: © 2009 Microchip Technology Inc. MCP3909 / DSPIC33F 3-PHASE Op Amp 3.2768 CLK MHz Gain ADC Control I/O dsPIC33FJ64GP206 SPI SPI +5V Power Supply Hardware Block Diagram. RS232 UART +3 ...
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... Input Signal Conditioning Circuit (Phase A). ) resistor is used 1 and C are used to filter high-fre- 112 /R and 125 126 3 1.0 kΩ CH0 110 C 111 1.0 kΩ CH0 111 C 112 1.0 kΩ CH1 108 C 109 1.0 kΩ CH1 109 C 110 MCP3909 © 2009 Microchip Technology Inc. , ...
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... In addition, a smaller temperature coefficient benefits meter start stabilization after startup. It takes a longer time for resistors with larger temperature coefficient to stabilize. Therefore, accurate measurements would require a longer wait after power-up. This affects the efficiency, or speed of meter calibration. © 2009 Microchip Technology Inc. Hardware Description and R (Using Phase example). ...
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... Clock Generation, Sampling Times and Calculation Frequencies. DS51723A-page 20 X100 MCLK input MCP3909 MCP3909 f = 12.8 ksps (Active Power) SAMPLE1 f = 6.4 ksps (Reactive Power, RMS Current / Voltage) SAMPLE2 f = 3.2 ksps (Harmonic Analysis, Distortion) SAMPLE3 DR t SAMPLE To dsPIC33F IRQ IC1 (Input Capture) DR Pulse © 2009 Microchip Technology Inc. ...
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... After each conversion, a positive pulse with the width of 4 clock cycles is output by the SDO pin of the MCP3909 device. IC generate an interrupt for every 2 falling edges, i.e., 1 data is read for every 2 conver- sions, thus realizing 6.4 ksps sampling rate. © 2009 Microchip Technology Inc. Hardware Description on the dsPIC33F is used to detect if A/D conversion is complete. 1 ...
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... SPI operates in slave mode. If UART interface is used to communicate with host MCU, then this interface cannot be used. Detect neutral current Detect boost voltage of neutral current Online debugging/programming interface Master clear input © 2009 Microchip Technology Inc. ...
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... The output pins for these LEDs are RC13 and RC14. The LED is on when the output is low. Figure 2-4 is the circuit of energy pulse output interface. RD3 RD2 RD1 FIGURE 2-4: © 2009 Microchip Technology Inc. Hardware Description 1 kΩ R 301 1 kΩ ...
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... FIGURE 2-5: Circuit of Neutral Line Detection. DS51723A-page 24 and R and connected to the emitter-follower of the 130 129 as emitter-follower output, generating the sampling 127 - U101_B 4.7 kΩ 470Ω 128 127 128 signals are REF Current_N 1.65V V REF © 2009 Microchip Technology Inc. ...
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... JP5 JP6 COILS Vo2 Vo1 FIGURE 2-6: Switching Power Supply Module (T4) and Additional Input Protection Circuitry. © 2009 Microchip Technology Inc. Hardware Description , RV1, RV2 and RV3 are C capacitors and varistors. They are used RV1 C1 0.1U 12V 100uf the integrated ferrite ...
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... INDUCTOR 1 L301 R316 INDUCTOR 470 D301 LED FIGURE 2-7: 5V and 3.3V LDO Modules. DS51723A-page 26 MCP1701(5V-SOT89) 2 Vin Vout + C337 100uf C322 CAP U306 MCP1700(3.3V-SOT23) 3 Vin Vout C323 CAP C338 C336 100uf 0.1uF 3. C339 C324 47uF CAP © 2009 Microchip Technology Inc. ...
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... Generation imp/kWh power pulse • UART communication 3.2 MAIN LOOP The main loop of the entire dsPIC33F program is shown in Figure 3-1. FIGURE 3-1: © 2009 Microchip Technology Inc. MCP3909 / DSPIC33F 3-PHASE Chapter 3. Firmware Main Program Initialize on-chip peripherals and variables and MCP3909 device Process UART comm ...
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... Parameters are calculated by the function Calculation(), which is executed once every 3 cycles of the power grid. Neutral current is detected by function ComputeNeutral- Current(), and computing is performed once every 16 cycles of the power grid. DS51723A-page 28 © 2009 Microchip Technology Inc. ...
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... Voltage and Current Distortion Of Each Phase • Voltage and Current Harmonic Contents Of Each Phase Note: Algorithms for all calculations are shown in Appendix C. “Power Calculation Theory”. FIGURE 3-2: © 2009 Microchip Technology Inc. Calculate function Calculate current Select sync. window RMS value function and ...
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... DFT transform is accomplished by function DFT(), which is written in assembly to take full advantages of the DSP feature of accumulated multiplication. Since an FFT algorithm cannot be used, and it takes longer to perform a DFT calculation, this is the most time-consuming process in the entire system. DS51723A-page 30 © 2009 Microchip Technology Inc. ...
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... Additional compensation to the power calculation is required, for phase compensation. This compensation is based on the present load current. The difference between signal frequency and the central frequency is also taken into consideration. Consequently computed power is compensated. © 2009 Microchip Technology Inc. ST harmonic). Firmware DS51723A-page 31 ...
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... The basic algorithm for measuring line frequency is based on the method described in Appendix A, Section C.4 “Measuring The Voltage/current Rms Value And Power Using Quasi-synchronous Sampling Algorithm”. Frequency will be measured once for every 3 times the data is sampled. DS51723A-page 32 © 2009 Microchip Technology Inc. ...
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... For the pulses to be outputted more uniformly, the clock resolution used to generate the pulses must be as high as possible. The interval of the IC1 interrupt is 156.25 µs, therefore, the resolution generated by the pulse can 156.25 µs. © 2009 Microchip Technology Inc. Sampling Sampling Cycle n+3 ...
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... End pulse output process. No Update pulse width counter, if counter > Yes Processing flip threshold, output rising edge of pulse and update active energy? energy accumulation register. No Return IC1 Interrupt Service Routine. © 2009 Microchip Technology Inc. ...
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... Calculate() will be called by the main flow to start computing all corresponding parameters. FIGURE 3-5: © 2009 Microchip Technology Inc. Read MCP3909 data Select phase A of The MCP3909 device, ...
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... FIGURE 3-6: DS51723A-page 36 Initialize MCP3909 Strobe all MCP3909 devices Reset the MCP3909 devices Wait for 4 CLK cycles Send instruction 0xac Set SPI to 16-bit mode Strobe phase A of the MCP3909 device End Initializing the MCP3909 Device Flow Chart. © 2009 Microchip Technology Inc. ...
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... UART TX 2 ADC 2 SPI2 none SPI1 none © 2009 Microchip Technology Inc. Data Length Data Field 1 byte N bytes Functional Description Fcy = 29.4912M, provided by an external 7.3728 Mz timer through an inter- nal PLL frequency doubler. System clock, used for timing. Its cycle is 10 ms. The interrupt flag may be set in the IRS ...
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... Adc.h I2Csubs.h Control EEPROM of off-chip I I2Csubs.c interrupt.h Declare macros, constants, local global variables, some of the global variables and functions used in interrupt.c. interrupt.c Set interrupts and ISRs. Asmcode.c Some assemble functions used in calculation. DS51723A-page 38 Description 2 C interface. © 2009 Microchip Technology Inc. ...
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... For high-accuracy energy meters, current ratio error needs to be segmented and calibrated for different current loads. The ratio error calibration of current channel uses a two-point calibration method. One point is calibrated when the load is at the rated current (I nal input condition (0.1 I © 2009 Microchip Technology Inc. MCP3909 / DSPIC33F 3-PHASE 10 and the PGA gain is 1 ...
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... At this time, the phase lag has not been calibrated, so when the input PF = 1.0, the measured value of the reactive power isn't equal to zero. 5. Repeat the above steps for Phases B and C. DS51723A-page 40 = 220V 5A. CAL 1. 220V 0.1 I CAL CAL = 220V, input current is the CAL © 2009 Microchip Technology Inc ...
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... When using two-point calibration, the compensation values of region 1 and 2 (0-0.075 I compensation values for region 3, 4 and 5 (0 are the same. B © 2009 Microchip Technology Inc. CURRENT REGIONS FOR PHASE CALIBRATION Current Range 0 - 0.075 I 0.075 I 0.2 I ...
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... A. Note: If the power metering error still can not meet the requirement, the meter can be calibrated a few more times. When doing so, simply input a new error value into the front-end of the meter. 4. Repeat for Phases B & C. DS51723A-page 42 © 2009 Microchip Technology Inc. ...
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... HDD space > • Microsoft Windows OS98 or later • Hardware COM interface 5.1.2 Installation 1. Unzip PM_Viewer setup.zip. 2. Double click on setup.exe. 3. Finish the installation according the prompt PM_Viewer.exe - Start -> Program -> Energy Meter ->PM_Viewer.exe. © 2009 Microchip Technology Inc. MCP3909 / DSPIC33F 3-PHASE DS51723A-page 43 ...
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... Click on the Link to establish communication with the demo. “Communication OK!” will be displayed on the bottom, if communication is established. FIGURE 5-1: DS51723A-page 44 Establising Communications. © 2009 Microchip Technology Inc. ...
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... BASIC PARAMETERS OUTPUT SCREEN FIGURE 5-2: 5.4 PHASE A/B/C HARMONIC OUTPUT SCREEN FIGURE 5-3: © 2009 Microchip Technology Inc. Basic Parameters Work Mode Screen. Phase N Harmonic Work Mode Screen. PC Software DS51723A-page 45 ...
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... MCP3909 / dsPIC33F 3-Phase Energy Meter Reference Design 5.5 DISTORTION RATE FIGURE 5-4: 5.6 HARMONIC POWER FIGURE 5-5: DS51723A-page 46 Distortion Mode Screen. Harmonic Power Work Mode Screen. © 2009 Microchip Technology Inc. ...
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... ENERGY ACCUMULATION FIGURE 5-6: 5.8 CALIBRATION STEP 1 - RESET ALL CALIBRATION 1. Select Reset All Calibration from the toolbar menu. 2. Meter Calibration Values are Reset. FIGURE 5-7: © 2009 Microchip Technology Inc. Energy Accumulation Work Mode Screen. Reset All Calibration Command. PC Software DS51723A-page 47 ...
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... LINEARITY CALIBRATION 1. Select Channel, either Voltage or Current. 2. Select Phase Select Region, either 100% or 10%. 4. Using a standard meter, supply the input conditions given here. 5. Enter the error recorded from the standard meter here. 6. Click the Set button. DS51723A-page 48 © 2009 Microchip Technology Inc. ...
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... Using a standard meter, supply the input conditions given here. 4. Click the Set Apparent button. 5. Enter the error recorded from the standard meter here. 6. Click the Set button. 7. Repeat steps 2-5 for the different regions. 8. Repeat for other 2 phases. © 2009 Microchip Technology Inc. PC Software DS51723A-page 49 ...
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... Select Region n. 3. Using a standard meter, supply the input conditions given here. 4. Enter the error recorded from the standard meter here. 5. Click the Set button. 6. Repeat steps 2-5 for the different regions. 7. Repeat for other 2 phases. DS51723A-page 50 © 2009 Microchip Technology Inc. ...
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... Write Calibration Values to Meter Write Phase Lag Calibration Values to Meter Write Power Calibration Values to Meter Write Energy Pulse Configuration - Active/Apparent Reset All Calibration Values Write Energy Pulse Constant © 2009 Microchip Technology Inc. MCP3909 / DSPIC33F 3-PHASE COMMAND STRINGS Command Description Command 0x41 ...
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... METER RESPONSE (104 BYTES) Data Command Data Field Length 0x43 0x62 98 bytes Check Sum STOP 1 Byte 1 Byte Check Sum STOP XX 0xE0 Check Sum STOP XX 0xE0 Check Sum STOP XX 0xE0 Check Sum STOP XX 0xE0 © 2009 Microchip Technology Inc. ...
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... TABLE 6-7: Data Field Byte 1,2 3-6 7-10 94-98 © 2009 Microchip Technology Inc. Meter Communications Protocol METER RESPONSE, TOTAL REQUEST FRAME, DETAILED DESCRIPTION Name Status Frequency Phase A Voltage Phase B Voltage Phase C Voltage Phase A Current Phase B Current Phase C Current Neutral Current ...
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... Command Data Field Length 0x43 0x00 0x00 METER RESPONSE (134 BYTES) Data Command Data Field Length 0x44 0x80 128 bytes R-0 R-0 R-0 PHA_S1 PHA_S0 bit Bit is unknown Check Sum STOP XX 0xE0 Check Sum STOP XX 0xE0 © 2009 Microchip Technology Inc. ...
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... Total Harmonic Distortion of Phase C Voltage 13-16 Total Harmonic Distortion of Phase A Current 17-20 Total Harmonic Distortion of Phase B Current 21-24 Total Harmonic Distortion of Phase C Current © 2009 Microchip Technology Inc. Meter Communications Protocol HARMONIC ANALYSIS DETAILED DESCRIPTION Description PC TO METER (7 BYTES) Data Command ...
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... Value Float, 4 Bytes Total Float, 4 Bytes Total Float, 4 Bytes Total Float, 4 Bytes Total Float, 4 Bytes Total Float, 4 Bytes Total Float, 4 Bytes Total Float, 4 Bytes Total Float, 4 Bytes Total Check Sum STOP XX 0xE0 Check Sum STOP XX 0xE0 © 2009 Microchip Technology Inc. ...
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... Harmonic Reactive Power Of Phase A 33-36 Harmonic Active Power Of Phase B 37-40 Harmonic Reactive Power Of Phase B 41-44 Harmonic Active Power Of Phase C 45-48 Harmonic Reactive Power Of Phase C © 2009 Microchip Technology Inc. Meter Communications Protocol PC TO METER (7 BYTES) Data Command Data Field Length 0x49 0x00 ...
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... Data Field Length 0x64 0 0x00 CALIBRATION OF GAIN AND OFFSET VALUES Description Check Sum STOP XX 0xE0 Check Sum STOP XX 0xE0 Value 0x01 = Phase A 0x02 = Phase B 0x03 = Phase C 0x01 = 10% 0x02 = 100% 0x00 = Current 0x01 = Voltage Float, 4 Bytes Total © 2009 Microchip Technology Inc. ...
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... START 0xFF, 0x00 TABLE 6-30: Data Field Byte 1 Phase Select 2 Current Range Select 3-6 Correction Factor (Error Being Calibrated Out) © 2009 Microchip Technology Inc. Meter Communications Protocol PC TO METER (12 BYTES) Data Command Data Field Length 0x63 6 0x06 METER RESPONSE (7 BYTES) ...
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... Phase A 0x02 = Phase B 0x03 = Phase C Check Sum STOP XX 0xE0 Check Sum STOP XX 0xE0 Value 0x01 = Phase A 0x02 = Phase B 0x03 = Phase C 0x00 = Active Power 0x01 = Apparent Power Check Sum STOP XX 0xE0 Check Sum STOP XX 0xE0 Value © 2009 Microchip Technology Inc. ...
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... CALIBRATE METER CONSTANT (ENERGY PULSE OUTPUT CONSTANT) TABLE 6-37: START 0x00, 0xFF TABLE 6-38: START 0xFF, 0x00 TABLE 6-39: Data Field Byte 1-2 Energy Constant © 2009 Microchip Technology Inc. Meter Communications Protocol PC TO METER (9 BYTES) Data Command Data Field Length 0x67 2 0x02 METER RESPONSE (7 BYTES) Data ...
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... MCP3909 / dsPIC33F 3-Phase Energy Meter Reference Design NOTES: DS51723A-page 62 © 2009 Microchip Technology Inc. ...
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... Power Supply Board - Assembly Drawing • Power Supply Board - Composite Drawing • Main Board - Assembly Drawing • Main Board - Composite Drawing A.2 SCHEMATICS AND PCB LAYOUT FIGURE A-1: © 2009 Microchip Technology Inc. MCP3909 / DSPIC33F 3-PHASE LAYER ORDER Top Layer Bottom Layer DS51723A-page 63 ...
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... MCP3909 / dsPIC33F 3-Phase Energy Meter Reference Design FIGURE A-2: POWER SUPPLY BOARD SCHEMATIC DS51723A-page 64 © 2009 Microchip Technology Inc. ...
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... FIGURE A-3: MAIN BOARD SCHEMATIC - PAGE 1 G1C G0C G1B G0B G1A G0A AD_CLK + + © 2009 Microchip Technology Inc. Schematics and Layouts + + + + DS51723A-page 65 ...
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... Vddcore Vss 56 25 GND Vdd AN11/RB11 3. RF0 AN10/RB10 58 23 RF1 AN9/RB9 59 22 RG1 AN8/RB8 60 21 RG0 AVss 61 20 GND RG14 AVdd G0A 62 19 3.3V RG12 PGD1/RB7 63 18 ICSPDAT RG13 PGC1/RB6 64 17 ICSPCLK VSS Gnd 1 1 © 2009 Microchip Technology Inc. ...
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... FIGURE A-5: POWER SUPPLY BOARD LAYOUT - ASSEMBLY DRAWING © 2009 Microchip Technology Inc. Schematics and Layouts DS51723A-page 67 ...
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... MCP3909 / dsPIC33F 3-Phase Energy Meter Reference Design FIGURE A-6: POWER SUPPLY BOARD LAYOUT - COMPOSITE DRAWING DS51723A-page 68 © 2009 Microchip Technology Inc. ...
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... FIGURE A-7: MAIN BOARD LAYOUT - ASSEMBLY DRAWING © 2009 Microchip Technology Inc. Schematics and Layouts DS51723A-page 69 ...
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... MCP3909 / dsPIC33F 3-Phase Energy Meter Reference Design FIGURE A-8: MAIN BOARD LAYOUT - COMPOSITE DRAWING DS51723A-page 70 © 2009 Microchip Technology Inc. ...
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... Current transformer 3 W1, W2 NOT POPULATE Note 1: The components listed in this Bill of Materials are representative of the PCB assembly. The released BOM used in manufacturing uses all RoHS-compliant components. © 2009 Microchip Technology Inc. MCP3909 / DSPIC33F 3-PHASE Description Manufacturer EPCOS Inc Panasonic — ...
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... Electronics Corp Tyco Electronics/Amp — Molex/Waldom Electronics Corp Part Number C0805C102K5RACTU ® GRM31CR71C106KAC7L - ECG ECJ-2VB1E104K C0805C105K8RACTU ECA-1EM471 ECJ-2VC1H220J 3057 RD005 19070-0040 LTL-4266N LTL-4236N LTL-4256N STBL2012-121 09-50-7031 08-50-0105 3051 RD005 3051 BK005 5520258-3 22-27-2061 22-27-2041 747091-2 — 08-65-0805 © 2009 Microchip Technology Inc. ...
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... Current transformer 1 T100 " DO NOT POPULATE Note 1: The components listed in this Bill of Materials are representative of the PCB assembly. The released BOM used in manufacturing uses all RoHS-compliant components. © 2009 Microchip Technology Inc. Bill Of Materials (BOM) Description Manufacturer Alpha Wire Company Alpha Wire ...
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... MCP3909 / dsPIC33F 3-Phase Energy Meter Reference Design NOTES: DS51723A-page 74 © 2009 Microchip Technology Inc. ...
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... The iterations can effectively reduce the impact of synchronization error over the mea- surement accuracy, and is one of the methods to realize accurate measurement of the frequency and harmonics under steady-state conditions. © 2009 Microchip Technology Inc. MCP3909 / DSPIC33F 3-PHASE DS51723A-page 75 ...
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... The 1 (α). π as its period, its value may be averaged through integration π , and it can be deduced that f( ∫ ) α π Δ ∫ ⋅ α Δ (α). © 2009 Microchip Technology Inc. ...
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... The quasi-synchronous recursive process mentioned above can be expressed as follows: For Equation C-4, the integral interval [x can be divided equally into sections, which results sampled data, ), (i=0,1,...,nxN), and we can iterate as follows: f(x i © 2009 Microchip Technology Inc. Power Calculation Theory β ∫ ...
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... – ∑ ⋅ ρ ⋅ -------------- - ∑ ρ ∑ 2 ⋅ ρ ⋅ 1 --------------- - ∑ ρ … × – 1 ∑ 2 ⋅ × --------------------------------- - – N × – × ∑ ρ – i × – N ρ ⋅ ρ ⋅ © 2009 Microchip Technology Inc. ...
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... Third iteration: © 2009 Microchip Technology Inc. Power Calculation Theory N 1 ∑ 3 ⋅ ρ ⋅ 2 -------------- - ∑ ρ ∑ ⋅ ρ ⋅ --------------- - ∑ ρ … × – 1 ∑ 3 ⋅ × --------------------------------- - – N × – × ∑ ρ – i × – N … ρ ⋅ ...
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... Equation C-9. EQUATION C-9: DS51723A-page ∑ – ⋅ ρ ⋅ -------------- - ∑ ρ ...... ...... N+1 N ...... ...... N+1 N ...... 3-Cycle Iterative Process. × ∑ n ⋅ η ⋅ --------------- - × ∑ η × ∑ ⋅ η ⋅ ----- - = × ∑ ⋅ ...... f 2N 2N+1 2N © 2009 Microchip Technology Inc. ...
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... In Figure C-3, the red curve is the characteristic of the window function, and the blue curve is input signal, and the green curve is the output signal. FIGURE C-3: Processing. © 2009 Microchip Technology Inc. Power Calculation Theory 1 ⋅ η ...
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... T 2 ∫ ⋅ ⋅ ⋅ ω ⋅ ) cos ∫ ⋅ ⋅ ⋅ ω ⋅ sin ∞ ∑ ⋅ ω ⋅ ϕ sin and ϕ , is ϕ atan ---- - ϕ sin ⋅ ω ⋅ © 2009 Microchip Technology Inc. ...
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... Make g(t) = f(t) • cos(K•ω•t), it can be proved that g(t) is also a periondic function with T as its period. Averaging g(t) in the range results in: EQUATION C-19 × g(t). Therefore EQUATION C-20: EQUATION C-21: Where N, n and η EQUATION C-22: EQUATION C-23: Where: EQUATION C-24: © 2009 Microchip Technology Inc. Power Calculation Theory ϕ cos ∫ ...
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... Equation C-31 with its initial phase angle shown in Equation C-29. EQUATION C-30: DS51723A-page 84 ∞ ∑ ⋅ ω ⋅ ---------- - + u ak cos sin ⋅ ω ⋅ cos sin ⋅ ω ⋅ ϕ sin ϕ atan ------- ⋅ ------ - --------------------------- - ⋅ ω ⋅ ⋅ ω ⋅ © 2009 Microchip Technology Inc. ...
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... Similarly, the effective values and initial phase angles of fundamental current and current of each other harmonic can be expressed as: EQUATION C-34: EQUATION C-35: The relationship between i EQUATION C-36: EQUATION C-37: Total current RMS can be expressed as: EQUATION C-38: © 2009 Microchip Technology Inc. Power Calculation Theory , u and U can be expressed as ⋅ ...
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... cos – ⋅ ϕ ϕ ϕ ϕ sin sin + cos cos ϕ ϕ sin – ⋅ ϕ ϕ ϕ ϕ sin cos – cos sin ⋅ ⋅ – ∞ ∑ total ∞ ∑ total © 2009 Microchip Technology Inc ...
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... If the frequency f Δf << f, then from Equation C-27, the fundamental signal can be expressed as: EQUATION C-45: If: EQUATION C-46: EQUATION C-47: EQUATION C-48: © 2009 Microchip Technology Inc. Power Calculation Theory to be measured is known definite value f, i.e ω ⋅ ϕ ...
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... N 1 ⎨ π ⋅ ⎪ ϕ ϕ π − − ⋅ ⎪ ϕ ϕ π − > ⎪ π ⋅ ⎩ © 2009 Microchip Technology Inc. ⎞ ⎠ ϕ and in 1 ...
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... Also, when the input frequency is around the multiple of cycle frequencies (52.459 Hz, 51.613 Hz, 50.794 Hz, 50.0 Hz, 49.231 Hz, 48.485 Hz and 47.761 Hz), the calculateion error is © 2009 Microchip Technology Inc. Power Calculation Theory Quasi-sync Algorithm Error Analysis of 3 Iterations. ...
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... Calcultion errors for all parameters are shown to be less than 0.015% after the correction. FIGURE C-5: Iterations. FIGURE C-6: Compensation. DS51723A-page 90 Error Analysis Of Improved Quasi-sync Calculation Using 3 Calculation Error Analysis After The Frequency Offset © 2009 Microchip Technology Inc. ...
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... APPARENT POWER OF EACH PHASE AND TOTAL APPARENT POWER Apparent power is defined as: EQUATION C-56: C.9 POWER FACTOR OF EACH PHASE AND TOTAL POWER FACTOR Power factor is defined as the ratio of active power to apparent power. The definition can be represented as shown in Equation C-57: EQUATION C-57: © 2009 Microchip Technology Inc. Power Calculation Theory ...
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... When reactive power Q < 0 (corresponding to quadrants III and IV), it means that loads are providing reactive energy to power grid, so the energy is defined as negative reactive energy. DS51723A-page ∫ ∑ ⋅ ⋅ Δ ∫ ) © 2009 Microchip Technology Inc. ...
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... A-有功电能;R—无功电能;R A-有功电能;R—无功电能;R A-有功电能;R—无功电能;R FIGURE C-7: © 2009 Microchip Technology Inc. Power Calculation Theory Reactive in (+R) Reactive in (+R) ...
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... 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. DS51723A-page 94 N ∑ ∑ × ------- THD = 100% THD × ------ THD = 100 © 2009 Microchip Technology Inc. ...
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... Rated Current (%) 50 120 © 2009 Microchip Technology Inc. Power Calculation Theory ε δ ⋅ – ------------------------ - f = 100 I 1 the rated current ratio the primary current the secondary current that passes I ...
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... Figure C typical curve for load current and the phase lag of a CT. Generally, phase lag of the output signal is great when the load current is small, and also increases at a fast rate. FIGURE C-8: DS51723A-page 96 Phase Lag Current Load Current Load Versus CT Phase Lag. © 2009 Microchip Technology Inc. ...
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... The MCP3909 device's current channel includes an adjustable gain amplifier. The ratio error must be recalibrated for different amplification, but only needs to be calibrated once under the same amplification conditions. © 2009 Microchip Technology Inc. Power Calculation Theory = Coefficient before correction ...
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... Input voltage Measurement Change Caused By Transformer Phase Lag ϕ , after PT and CT, the variation Δϕ ϕ = – Δ Principle Of Phase Lag Correction. Inductive Load Input voltage θ CT Output current Δθ Input current Capacitive Load ϕ © 2009 Microchip Technology Inc. ...
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... The error can be obtained from the output of the meter calibration workbench. EQUATION C-73: © 2009 Microchip Technology Inc. Power Calculation Theory ⋅ ⋅ φ ...
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... Microchip Technology Inc. ...
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... To avoid complexity in calculation and to maximize the correction precision, the following equations may be used to approximate K small. EQUATION C-80: EQUATION C-81: © 2009 Microchip Technology Inc. Power Calculation Theory and Δ Δϕ ≈ Δϕ ⋅ Δϕ ----- - sin k' = cos cos – ...
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... MCP3909 / dsPIC33F 3-Phase Energy Meter Reference Design NOTES: DS51723A-page 102 © 2009 Microchip Technology Inc. ...
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... This is provided for download from Microchip’s website, file names and checksums below. At the same time you need to change the crystal to provide clock for metering IC. TABLE D-1: Line Frequency © 2009 Microchip Technology Inc. MCP3909 / DSPIC33F 3-PHASE FIRMWARE FILES Firmware Name Hex File Checksum PM_1_50.ZIP PM_1_60.ZIP ...
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... Fax: 886-3-6578-370 Taiwan - Kaohsiung Tel: 886-7-536-4818 Fax: 886-7-536-4803 Taiwan - Taipei Tel: 886-2-2500-6610 Fax: 886-2-2508-0102 Thailand - Bangkok Tel: 66-2-694-1351 Fax: 66-2-694-1350 © 2009 Microchip Technology Inc. EUROPE Austria - Wels Tel: 43-7242-2244-39 Fax: 43-7242-2244-393 Denmark - Copenhagen Tel: 45-4450-2828 Fax: 45-4485-2829 France - Paris Tel: 33-1-69-53-63-20 ...