PL3201-SOC For 1PH Multifunction PLC Meter
|· 0.35µ VLSI Mixed Signal CMOS Technology
· Proprietary System-on-Chip design with multiple individual IPRs
· On-Chip High precision Energy Measurement module for both active and reactive energies
· High Accuracy measurement – supports IEC 60687, IEC 61036, IEC 61268, IEC 62053-21 to 23
· 2 nos. 16 bit Second-order Σ-Δ ADC Current Channel inputs with built in PGA (4 programmable gains – 4,8,16 and 32) + 1 Voltage channel
· On-chip digital ASME Y14.5 logic circuit for positive/negative power direction indication
· Active Energy Error < 0.1% over dynamic range of 1000:1
· Reactive Energy Error < 0.2% over dynamic range of 1000:1
· Built-in Frequency, RMS Voltage, RMS Current measurement modules
· Accurate Reactive Energy Measurement up to 21st harmonic
· Enhanced On-chip 8051 Microcontroller
· 256 B + 1KB of SRAM
· 16KB Program Memory E2PROM
· 60B Data Memory E2PROM
· Spread spectrum communication modulation/demodulation circuit for PLCC
|· 2 nos Full Duplex, multi-function programmable UARTs (Universal Asynchronous Receiver/Transmitter)
· 3 nos. 8/16 bits timing/counter,
· 1 no. Watch Dog Timer
· 3 nos. External Interrupts
· Internal programmable frequency generator
· Internal Infra Red Decoder Circuitry
· Built-in 4×32 LCD Driver or Built-in 8×8 segment LED Display control circuit (External Driving circuit)
· Digitally calibrated Real Time Clock with Seconds pulse output
· Embed the temperature frequency converter which can compensate the precision of energy measurement and Real Time Clock linearly according to different segments
· On-Chip temperature monitor and compensation for measurement circuits as well as RTC
· High precision ASME B31.3 Internal Voltage reference
· Serial programming interface for program memory and supports in-system programming (ISP)
· Single +5V supply operation
· Power supply monitoring circuitry.
· Wide operating temperature of –40oC to +85oC
· 100 pin Industrial grade LQFP packaging
PL3201 is a device from PL3200 series System-on-Chip (SoC) family and it needs neither external computation engine or measurement components nor peripherals components. The external support devices are very minimal. Thus it is an ideal device for realization of a cost effective and feature loaded multifunction energy meter.
This IC performs a host of advanced power measurements at low cost. The IC will measure instantaneous voltage, current and power; Irms and Vrms; average real/apparent/reactive power; fundamental power; harmonic power; and line frequency. These devices integrate all of the required silicon except for the 3-V or 5-V power supply required to power the chip. PL3201 single-chip solution for the advanced function energy meters reduce the cost differential between these stepper-motor display and LCD display meters. The designs based on this chip have further reduced the cost of advanced multi function meters.
The current and voltage signals are digitized, using Analogue to Digital Converters and thereafter, calculations are made in a micro-controller (on-chip enhanced 8051). Power is calculated by multiplying the current and voltage signals. Even for non-sinusoidal current and voltage waveforms and different power factors, power gets computed correctly. Digital processing of signals offers advantages of stable and accurate calculations. Digital processing is addressed through a programmable on-chip function DSP (Digital Signal Processing) solution. It is possible to reconfigure the metering system, thereby allowing the Utility to decide on the services to be rendered, such as Power outage disconnect, prepayment, load disconnect etc.
By far the unique realizable feature of designing with PL3201 is its ability of implementation of Power Line Carrier Communication capability in the meter. This enables the meter to be directly deployed for Automated Meter Reading applications without any modifications in the meter. High frequencies have good propagation properties on high voltage lines and as such, have been extensively used without any problem being experienced. The same is, however, not the case with distribution lines due to changes in the line impedance at transitions. To overcome the problem, lower frequencies have been resorted to. Over a period of time, Ripple Carrier Systems at approx. 10 Hz range have evolved, which do not suffer much attenuation on distribution lines. We also know that with lower frequencies, the size of the equipment tends to increase, as a result of which the Ripple Technology can be used for communicating only in one direction, say for load management, but it is not suited for reading meters. Ripple technology evolved into Sequential Waveform Distortion, which simply distorts the Voltage waveform and transmits it down the line. This triggers a Transceiver, which produces signals (large current spikes) to be received at the sub-station. This way, the computer can read a meter. This is called Ultra Narrow Bandwidth Power Line Carrier Technology. It has many advantages over other systems by way of extremely small size of transmitters, which can fit into a normal size Kwh meter.
The meters can transmit data continuously and thousands of them can be on line simultaneously. They are distinguished from one another by the distorted waveform, which is unique for each transmitter. The Receiver, which is a Digital Signal Processor, is able to discern thousands of transmitters on account of their unique signatures.
The power line carrier communication unit integrated in this design is based on QPSK (Quadratic Phase Shift Keying) modulation mode and multiple address communication mode and changeable pseudorandom code speed (band width). Its carrier center frequency is 120 KHZ; the pseudorandom code speed can reach 15K and 30K, in view of the QPSK modulation technology. The data rates would be 1Kbps and 500bps depending on the pseudorandom code deployed.