POWER MANGEMENT BY SOC USING POWERLINE Communication

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					       POWER MANGEMENT BY SOC USING POWERLINE
                   Communication
ABSTRACT:

SoC Uses Powerline Communications to Control Embedded Applications:
System-on-a-chip features programmable flexibility to configure embedded applications controlled by
powerline communications, such as lighting, industrial control, automatic metering, home automation, and
smart energy management.

The PSoC core integrates multiple functions beyond communication, such as power measurement,
system management and LCD drive. Besides its flexibility and integration, this system offers reliability with
100% powerline data transmission success rates on standard networks and offers retries built into its
coding in case data is dropped on noisy or low impedance networks.”

powerlines would appear to be a potential communications medium for command and control of external
devices. This application is complicated because it is difficult to predict the quality and reliability of
communications over existing powerlines because of the associated variables of noise, impedance and
line quality. operating conditions with a design that enables secure and reliable communications up to
11,500 feet.




The PLC system can provide data communication over other ac-dc powerlines as well with the appropriate
external coupling circuit. The 110Vac and 240Vac designs comply with the powerline usage regulations
The power management through power line communication are less cost and efficient way for
implementing in most commercial and house hold areas because medium to be used were existing
transmission line and it was used power management, industrial control, automatic metering,etc….



POWER MANGEMENT BY SOC USING POWERLINE COMMUNICATION

INTRODUCTION:
Power line communication were only used between sub-station,but it was more helpful in
power management and other useful application through soc. System-on-a-chip features
programmable flexibility to configure embedded applications controlled by powerline
communications, such as lighting, industrial control, automatic metering, home automation,
and smart energy management. The system offers the flexibility to communicate over high-
voltage and low-voltage powerlines smart energy management applications.


POWERLINE COMMUNICATION:
Communication over a existing high-voltage or low-voltage grid are having higher bit-rates
and more reliable communication over the power lines. The main advantage with power-line
communication is the use of an existing infrastructure. Wires exist to every household
connected to the power-line network.


POWERLINE COMMUNICATION IN POWER MANGEMENT :
powerlines would appear to be a potential communications medium for command and control
of external devices. This application is complicated because it is difficult to predict the quality
and reliability of communications over existing powerlines because of the associated
variables of noise, impedance and line quality. operating conditions with a design that
enables secure and reliable communications up to 11,500 feet.
PLC CORE:

Adding the PLC Core to the Cypress SoC inserts the application coding obtained from the
programmable analog and digital blocks and microcontroller of the PSoC architecture. This
combination provides a single hardware platform for multiple applications, reducing BOM
cost, board size and chip count while improving manufacturability. In response to the
requirements for the specific application, the PLC Core uses two-way communication with
the PSoC core, which employs a highly configurable system-on-chip architecture for
embedded control design.

    Powerline modem (PHY) physical layer - based on Frequency Shift Keying (FSK)
     modulation Configurable baud rates up to 2400 bps
    Configurable Tx, Rx gains and Band In Use (BIU) threshold
    Powerline optimized network protocol
    Integrated data link, transport, and network layers
    Bidirectional half duplex communication
    8-bit CRC error detection to minimize data loss
    SPI, UART and I2C enabled powerline application layer
In the physical layer (PHY) shown in




the digital transmitter serializes digital data from the network layer and feeds it to the
modulator input. The modulator divides the local oscillator frequency by a definite factor
depending on whether the input data is high level logic “1” or low level logic “0”. It then
generates a square wave at 133.3 kHz (logic “0”) or 131.8 kHz (logic “1”), which is then fed
to the programmable gain amplifier to generate FSK modulated signals that are applied to
the Powerline Coupling Circuit. This enables tunable amplification of the signal. Using this
amplifier, the amplitude of the signal coming out of the chip can be varied between 55 mV to
3.5V. This feature enables the PLC modem to communicate effectively even when the
channel is noisy. The logic “1” frequency can also be configured as 130.4 kHz for wider FSK
deviation.
Incoming FSK signals (RX) from the Powerline Coupling Circuit are sent to a high frequency
(HF) band pass filter that filters out-of-band frequency components and outputs a filtered
signal within the desired spectrum of 125 kHz to 140 kHz for further demodulation. The mixer
block multiplies the filtered FSK signals with a locally generated signal to produce
heterodyned frequencies.

Intermediate frequency (IF) band pass filters further remove out-of-band noise as required
for further demodulation. This signal is fed to a correlator that produces a dc component
(consisting of logic “1” and “0”) and a higher frequency component.

The correlator output feeds a low pass filter (LPF) that outputs only the demodulated digital
data at 2400 baud and suppresses all other higher frequency components generated in the
correlation process. The hysteresis comparator digitizes LPF output, which eliminates the
effects of correlator delay and false logic triggers due to noise. The digital receiver
deserializes this data and outputs it to the network layer for interpretation.

In response to the requirements for the specific application, the PLC Core uses two-way
communication with the PSoC core, which employs a highly configurable system-on-chip
architecture for embedded control design.

PSOC CORE

The PSoC platform consists of controller devices that replace multiple, traditional MCU-
based system components with one, low-cost, single-chip programmable device. PSoC
devices include configurable blocks of analog and digital logic, and programmable
interconnects. This architecture enables the user to create customized peripheral
configurations that match the requirements of each individual application.

Among the members of this family are cost-optimized fixed-function device with an I2C
interface (CY8CPLC10), programmable PSoC-based devices (CY8CPLC20), and
programmable PSoC-based devices optimized for LED support (CY8CLED16P01). The
CY8CPLC10 is available in a 28-pin SSOP package, while the CY8CPLC20 and
CY8CLED16P01 devices come in 28-pin SSOP, 48-pin QFN and 100-pin TQFP packages.

For example, the CY8PLC20 contains:

Programmable System Resources

      Up to 14-Bit ADCs
      Up to 9-Bit DACs
      Programmable gain amplifiers
      Programmable Filters and Comparators
      to 32-bit timers, counters, and PWMs
      CRC and PRS modules
      Up to four full duplex UARTs
      Multiple SPI masters or slaves
      Connectable to all GPIO pins



POWERLINE COUPLING CIRCUIT:




The Powerline Coupling Circuit (Figure 1) is an external unit that couples low voltage signals
from the PLC Core to the powerline. Included is an isolated offline switch-mode power supply
that operates from the same powerline that carries the communication signaling. The circuit
meets the requirements for signaling on high voltage lines according to the EN50065-1:2001
and FCC Part 15 standard. It operates with 110V/240Vac and 12V/24V ac-dc powerlines.
The coupling circuit receives the FSK transmit signal, TX, originated in the PLC core as a low
amplitude (~125 mVp-p configurable from 55mVp-p to 3.5Vp-p), unfiltered signal and applies
it to the transmit filter and amplification block. The transmit filter is a fourth order Chebyshev
response band pass filter, designed for 1.5 dB maximum pass band ripple. It provides 16.5
dB of gain at the center frequency of 133 kHz, suppression of -20 dBc at the 150 kHz band
limit, and -50 dBc and -60 dBc at the second and third carrier harmonics, respectively. The
transmit output signal drives isolation transformer T1 that connects to the powerline. A 1.0
µF capacitor (C14) removes the DC offset for the transmitter on the device side, and a 0.15
µF capacitor (C9) along with transformer T1 forms a high pass filter blocking the 50/60 Hz
HV Powerline carrier signal and passing the 133 kHz PLC signal.

LOW IMPEDANCE

The receive signal is coupled from the line into the PLC Core via isolation transformer, T1,
used by the transmitter. Transformer T1 must provide low impedance at the signal frequency
and low leakage. An internal 0.01 µF capacitor provides dc isolation and a 2.0 kΩ input
resistor sets the receiver's input impedance. This resistor, along with two diodes, provides
signal limiting to protect the circuit from high amplitude transmitter signals and any large
signals coupled in from the line.

The receive filter consists of a 1mH inductor, 150 pF capacitor and the 2.0 kΩ resistor. It
rejects of out-of-band interference, such as AM broadcast signals that might be coupled from
the line and could swamp the internal receiver circuit.

The offline switch-mode power supply is a standard isolated flyback converter using a full-
bridge input rectifier. A 1.0Ω input resistor from the line provides in-rush current limiting. An
MOV transient voltage suppressor provides against transients and an input fuse protects
against an overcurrent condition. This power converter is intended for worldwide operation
from line voltages ranging from 90Vac to 240Vac. This results in peak voltages approaching
350V dc, so the associated filter capacitors must be rated to safely accept these peak
values.




Conclusion:
System offers the flexibility to communicate over high-voltage and low-voltage powerlines for
lighting and industrial control, home automation, automatic meter reading and smart energy
management applications.

Powerline communication is less cost to implement and it was more helpful industrial control
and power management in efficient way.SOC ,PSOC was main architecture for power
management and other control applications using powerline communication.

				
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posted:5/29/2012
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