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A Smart-Grid Simulatorretargeting VCS/VMM technology

Srikanth Jadcherla

Vishwanath. S

Jyothsna. K

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Agenda

Smart Grid Overview

Project Goal and Progress

Project Details

Results

Demo

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Smart Grid in one slide..

Regulatory pressures on loads

Clean, local energy

Climate change

Energy Gap

Energy Security

Energy Star

Dynamic revenue

Loss reduction

Direct DC

All of these require real time communication between generators, loads and transmission networks Smart Grid

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Old Grid vs. New

All AC grid- customer view

High Capacity generators, isolated

No load-supply negotiation

Unilateral power outages

Minimal energy measurement

AC, Direct DC

Interspersed low-medium generation

Smart RT load-supply negotiation

Dynamic, Interactive load shedding

Sophisticated energy monitoring/reporting

This calls for very sophisticated communication

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Smart Grid is the new “BUS”

1 MW 700 MW

Washing machine

TV/ DVR/ PCMixed Signal SOC + S/WMixed Signal SOC + S/W

CentralPower Mgmt.

This system can be predictively modeled with VCS/VMM

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Smart Grid Simulator Objectives Retarget VCS/VMM to create a flexible,

extensible simulator/model of a large city- Use Verilog/SystemVerilog to model appliances,

homes, offices, cities, generators etc. – all grid components

- Constrained random techniques to create realistic event profiles e.g. Cloudy days, refrigerator open-close

- Create reference architectures and protocols• Focus on macro level, home/office managers,

end-device managers

Help to predict metrics on grid characteristics

- Stability- Command/response studies - Revenue management models

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Agenda

Smart Grid Overview

Project Goal and Progress

Project Details

Results

Demo

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Project Goal

Build a behavioural model of a city.

Create a standard, extensible framework

Standardize Home controller IP and protocol

Get requirements from potential partners/customers

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Project Progress

Work Completed– Behavioral model of a home/colony

• 6 devices modeled per home• Home controller developed• Extensible models to build a colony • SystemVerilog used for design and testbench

What next – Behavioral models for a neighborhood/city– VMM for verification

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Agenda

Smart Grid Overview

Project Goal and Progress

Project Details

Results Demo

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Hierarchical Distribution of a Home

HOME

GARAGE FMLY. ROOM KITCHEN M.BEDROOM CH. BEDROOM OFFICE

WATER HEATER

AIR HEATER/COOLER

WASHING MACHINE

DRYER

VACUUM CLEANER

LIGHTS

DOOROPENER

TV

DVD PLAYER

DVR

GAME SETS

LIGHTS

MUSIC SYSTEM

SET TOP BOX/RECIEVER

FRIDGEMICROWAVEOVENTOASTERMIXER/BLENDERCOFFEE MAKER

ELECTRIC STOVE LIGHTS

ELECTRIC KETTLESDISHWASHER

LIGHTS

TV*

FRIDGE*

FANS/ COOLERS

COMPUTER

FANS/ COOLERS

LIGHTS

COMPUTERS/LAPTOPS

MODEMS

ROUTERS

PRINTERS/SCANNERS

SOLAR PVs DG SETS INVERTERS

MISC. : WATER PURIFIERS, AIR CONDITIONERS(centralized), GEYSERS, ELECTRIC IRON, BLOW / HAIR DRYERS etc.

* indicates OPTIONAL appliances

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Smart Grid enabled home interface view

Grid Interface

HOME CONTROLLER

DEVICE1 DEVICE4DEVICE3DEVICE2

User Inputs

Device Response

Device Response

smart

pwr_on

pwr_consumed

HOMECNTRL

Device

smart_ack

Standard device interface and protocol

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What we have built :Energy models/use profiles for devicesLanguage : Verilog

Similar to SDPD .lib models

Door open : 100WCompressor : 700 WFreezer open : 65WFn (Ambient T, Setting T)

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What we have built :Smart Mode/Green Ring “hardware”Language : Verilog

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clk

pwr_on

smart

load

main_pwr

wash_ time integer

override

respond

integerpwr_consumed_wm

dry_time integer

smart_ack

rinse_time integer done

WASHING MACHINE

Interface of a Washing Machine

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Specifications

A washing machine has three stages of operation, viz, washing, rinsing and drying

Each stage consumes different amount of power,typically,

filling+agitating(washing) – 400 watts

filling+pumping (rinsing) – 350 watts

spin drying – 800 watts

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‘main_pwr’ is the power on/off signal at the device level, issued by the user

‘pwr_on’ is the power on/off signal from the ‘home controller’, issued considering the allowed power limitations

‘smart’ is the smart control signal ‘load’ describes the volume of the load (small,

medium,large,extra large)which would in turn specify the power consumed by each action

‘wash_time’ is the time duration for wash cycle ‘rinse_time’ is the duration for rinse cycle ‘dry_time’ is the duration for drying cycle

Specifications(contd.)

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‘override’ tells the system to proceed with the usual operation even when ‘smart’ is asserted

‘respond’ tells the system to respond to the ‘smart’ signal i.e., to go to the ‘low power’ mode

‘smart_ack’ is high when the device alters its usual operation as a response to the ‘smart’ signal

‘pwr_consumed_wm’ is the total power consumed by the washing machine in a particular state

‘done’ is high when the three processes, viz., washing, rinsing, drying are all finished and the machine is ready to consider new inputs

Specifications(contd.)

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OFF

ON /READ /

FILL

WASH

RINSE

DRY / SPIN

LOW POWER

smart=1 && override=0

smart=1 && override=0

Timer > wash/rinse_timeAND smart=0 || override=1

State Machine

smart=0 OR smart=1 && override=0

pwr_on && main_pwr

else

smart=1 && override=0 /1 && respond=0/1

smart=0 || smart=1 && override =1

smart=1 && override=0 && respond=1

smart=1 && override=0 && respond=1

smart=0 || smart=1 && override =1

smart=1 && override=0 /1 && respond=0/1

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OFF state is where either the ‘main_pwr’ or the ‘pwr_on’ signal is low, and the device is not functional

ON (stand by)state is where the device reads the input values but does not perform any action

WASH is where the device washes for ‘wash_time’ minutes

RINSE is where the device rinses for ‘rinse_time’ minutes

DRY is where the device dries for ‘dry_time’ minutes LOW POWER is where the device performs wash and

rinse processes in a low power mode, wherein power consumption is low

States of a Washing Machine

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main_pwr pwr_on smart override respond State(Q(n+1))

x 0 x x x OFF

0 x x x x OFF

1 1 0 x x ON / Qn

1 1 1 1 0 Qn

1 1 1 0 1

LOW_POWER

1 1 1 1 1 ON

1 1 1 0 0 ON

Response table

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What we have built :A home controller “IP” moduleLanguage : Verilog

Smart homecontroller

Addition to Smart meters/home

monitors

Non Trivial – interface, protocol,

over rides etc.

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Interface of a Home Controller

clksmart

pwr_oncentral_override

integer

integer

integer

[6:1] smart_device

pwr_contr [6:1]

total_pwrinteger

pwr_consumed_t

allowed_pwr

indicator

pwr_consumed_tv

pwr_consumed_wm

pwr_consumed_fan

pwr_consumed_ac

pwr_consumed_oven

main_pwr_t main_pwr_tv

main_pwr_wm

main_pwr_fanmain_pwr_ac

main_pwr_oven

HOME CONTROLLER

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Inputs:

‘pwr_on’ is the power on/off signal to the home controller. ‘smart’ is the external smart ‘control’ signal ‘central_override’ is the signal to override external ‘smart’

and ‘allowed_pwr’ limitations ‘main_pwr_t,main_pwr_ac,main_pwr_wm,main_pwr_ove

n,main_pwr_tv,main_pwr_fan’ are the power on/off signals at the device levels, issued by the user, for the 6 devices respectively

‘pwr_consumed_t,pwr_consumed_ac,pwr_consumed_tv,pwr_consumed_wm,pwr_consumed_fan,pwr_consumed_oven’ are the 6 integers specifying the instantaneous power consumed by each device

Specifications

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‘allowed_pwr’ is the maximum power consumption that can be allowed at any instant. It is generated by a central control authority

Outputs: ‘smart_device’ is a 6-bit signal, each bit pertaining to one

device, which is asserted when the external ‘smart’ signal is asserted

‘pwr_contr’ is an array of 6, 1-bit values which are power on/off signals to the devices(in the order of their priority) from the home controller, issued depending on the (total_pwr + PEAK_PWR[i] <= allowed_pwr) condition

‘indicator’ goes high when ‘smart_device’ is asserted and the power is still not within the ‘allowed_pwr’ limits

Specifications (contd.)

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What we have built :A randomized neighborhood simulationLanguage : SystemVerilog

Testbench/ Grid Controller LayerCreate various conditions and study responses

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Example 1 : Grid reduces allowed power Devices get “throttled”

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Smart is high and override low, total power is getting reduced.Smart and override are high, total power is high.

Example 1 : Grid asserts smart mode Devices get “throttled” to Min Power, until user “Override”.)

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Agenda

Smart Grid Overview

Project Goal and Progress

Project Details

Results Demo

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Scenario 1 : power consumption of a home

Power(watts)

Time (10 units = 1 hr.)

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Scenario 1 :power consumption profile with smart

Power(watts)

Time (10 units = 1hr)

smart = 1

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Scenario 1 :comparison of power consumption (with and without smart)

Power (watts)

Time (10 units = 1hr)

5 devices operating in low power mode5 devices operating in low power mode

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Scenario 1 : power consumption profile with both smart and override

Time (10 units = 1hr)

Power(watts)

Smart asserted

override smart

Override = 0,smart mode

resumes

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Scenario 1 : comparison of power consumption with smart

( with and without override)

Power(watts)

Time (10 units = 1hr)

smart = 1

Smart asserted

override smart

Override = 0,smart mode

resumes

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Time

Power(watts)

(10 units = 1hr)

Scenario 1 : Comparison of total power consumed by 5 homes ( with and without smart)

smart = 1

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Time (10 units = 1 hr)

Power(watts)

Scenario2 : Comparison of total power consumed by 5 homes( with both smart and override)

smart = 1

override = 1

Smart asserted

override smart

Override = 0,smart mode

resumes

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Agenda

Smart Grid Overview

Project Goal and Progress

Project Details

Results Demo

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The simulation is assumed to run for 24 hours

Considering 100 clock cycles as 1 hr, the simulation runs

for 2400 clock cycles

Washing machine : it is turned on thrice a day,

randomly between 6 am to 10 am, 12 noon to 2 pm and

7 pm to 9 pm i.e., 600 to 1000 and 1900 to 2100 cycles

Toaster : it is turned on 5 times randomly between 7 am

to 10 am i.e., 700 to 1000 clock cycles

Television : it is turned on 20 times randomly between

8am to 12 am i.e., between 800 to 2400 cycles

Time profile of devices

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Air conditioner : it is turned on 5 times randomly between 12pm to 4pm, 10pm to 12 am and 12am to 4 am i.e., 1200 to 1600, 2200 to 2400, 00 to 400 cycles

Fan : it is turned on 20 times randomly between 7am to 10 pm and is constantly turned on between 10pm to 6 am

i.e., 700 to 2200 – random on/off

2200 to 2400 and 00 to 600 – on

Oven : it is turned on 10 times randomly between 7 am to 10 am, 1 pm to 3 pm and 7 pm to 9 pm i.e., 700 to 1000, 1300 to 1500, 1900 to 2100 cycles

Time profile of devices (contd.)

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Smart Grid Simulator– Main modeling capability– Can do a small neighborhood now

Power Models for appliances

Green mode “state machines” for appliances

Home controller AND interface/protocol

Just to recap : we have new “babies”

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