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8/4/15 2:29 PM C:\Users\Indul...\PMU_for_PublicUse_setup.m 1 of 3

clear all;close all;

fprintf(1,'==========================================================================================\n');fprintf(1,'========\n');fprintf(1,'==== Setup TickTock PMU Demonstrations====\n');fprintf(1,'========\n');fprintf(1,'==========================================================================================\n');

FloatToInt32CastingMethod_Round = 0

% Overall scenario and sampling configuration, common for P and M classSampleFreq = 10000TsSampling = 1/SampleFreq;

f0_SigGen = 50f0_PMU = 50Fs_PMU = f0_PMU

%% Calibration factors for hardware and anti-alias filter

% The calibrations are given in the form of 2nd-order polynomial coefficients.%% Inside the PMU, the measured (linear) amplitude is multiplied by:% GainCoeff(1)*f^2+GainCoeff(2)*f+GainCoeff(3)% where f is in Hz.% So the GainCoeffs should represent the linear attenuation of any hardware% such as VTs, anti-alias filters, etc.%% Inside the PMU, the measured phase (in radians) is advanced by:% PhaseCoeff(1)*f^2+PhaseCoeff(2)*f+PhaseCoeff(3)% where f is in Hz.% So the PhaseCoeffs should represent the phase lags of any hardware% such as VTs, anti-alias filters, etc.

% In this simple example simulation, I have stripped out the anti-alias% filters and there are no modelled effects of hardware% or finite ADC sampling time/delay (the ADC is assumed to be "instant").

% Therefore:HardwareAndAntiAlias_GainCorrectCoeffs = [0 0 1.0]; %(The measured amplitude is alwaysmultiplied by 1.0 at any f)HardwareAndAntiAlias_PhaseCorrectCoeffs = [0 0 0]; %(The measured phase is leftunaltered at any f)


% However, if you want to insert anti-alias filters or sensors with% bandwith-related effects into the simulation, you can do so using code% like that shown below. The effects of the different components can be% carefully combined into single 3-element vectors for amplitude and phase.

% If using Simulink to simulate anti-alias filters, be very careful since% it is very easy to accidentally create phase lags due to discrete% low-pass filter models which do not match those you expect from theory.% If you do this, you will also need to simulate the analogue signals and% low-pass filters using a much smaller timestep (or continuous timestep)% than the PMU sampling timestep. When you do this, you will need to% introduce rate transitions to simulate the effects of the ADC.% Be careful to configure the rate transition blocks correctly, or you can% end up with extra sampling delays which you didn't expect.

CalFreqs = [40 ; 55 ; 70]; % Frequencies for calibrations of hardware, anti-alias filters

Hardware_gain_response_linear = [ 1.0 ; 1.0 ; 1.0 ]; % Linear gains of measurementhardware at cal freqs (Measurement will be corrected by attenuating by these amounts)Hardware_phase_response_degrees = [ 0.0 ; 0.0 ; 0.0 ]; % Phases of measurement hardwareat cal freqs (Measurement will be corrected by lagging by these amounts)

% In the standard, the P class device does not have an anti-alias filter.% Here I have allowed for the same (filtered) path into shared P and M-class PMUs% since the LPF CAN be used if sample rate is high and it adds very little latency.AntiAlias_Fc = 1e9; % max([SampleFreq/4,Fnom*5]);% Do not allow filters with low cutoffs at low sampling rates, since these% introduce too much latency

SamplingDelay = (0.0e-6)/2; % The time delay between the sampling "instant" and the UTCtimeclock% This might need to be phase by phase for multiplexed ADCs% Here I assume that 3 parallel ADC channels are used with synchronised% sampling, and that the sampled value is averaged over 0.0us IMMEDIATELY% prior to the start of the frame (where the UTC timeclock value is% synchonised to). Note. This delay is not easy to simulate acurately with% simple delays, so, I have kept this value to zero just now.

Hardware_GainCorrectCoeffs = polyfit(CalFreqs,1./Hardware_gain_response_linear,2)Hardware_PhaseCorrectCoeffs = polyfit(CalFreqs,-Hardware_phase_response_degrees*pi/180,2)

% The cal for a simple 1st-order LPF.% Adjust for more complex filters as appropriate

s = 2*pi*j*CalFreqs;AntiAlias_Response = 1./(1+s/(2*pi*AntiAlias_Fc));AntiAliasMag=abs(AntiAlias_Response)AntiAliasPhase=angle(AntiAlias_Response);

AntiAliasPhaseDeg = AntiAliasPhase*180/pi


AntiAlias_GainCorrectCoeffs = polyfit(CalFreqs,1./AntiAliasMag,2);AntiAlias_PhaseCorrectCoeffs = polyfit(CalFreqs,-AntiAliasPhase,2);

% HardwareAndAntiAlias_GainCorrectCoeffs = MFAJR_MultiplicativeCalCompCombine(Hardware_GainCorrectCoeffs,AntiAlias_GainCorrectCoeffs,CalFreqs)% HardwareAndAntiAlias_PhaseCorrectCoeffs = MFAJR_AdditiveCalCompCombine(Hardware_PhaseCorrectCoeffs,AntiAlias_PhaseCorrectCoeffs,CalFreqs)

HardwareAndAntiAlias_GainCorrectCoeffs = MFAJR_MultiplicativeCalCompCombineNoSymToolbox(Hardware_GainCorrectCoeffs,AntiAlias_GainCorrectCoeffs,CalFreqs)HardwareAndAntiAlias_PhaseCorrectCoeffs = MFAJR_AdditiveCalCompCombineNoSymToolbox(Hardware_PhaseCorrectCoeffs,AntiAlias_PhaseCorrectCoeffs,CalFreqs)

% Add phase delay due to sample "instant" relative to UTC time (start of frame)% This is a linear phase slope against frequencySamplingDelayPhasePerHz = 2*pi*SamplingDelay;% Add this to proportional element of calHardwareAndAntiAlias_PhaseCorrectCoeffs(2) = HardwareAndAntiAlias_PhaseCorrectCoeffs(2)+SamplingDelayPhasePerHz

%% Scenario

InitialSettlingTime = 5ScenarioLength = 30FastForwardScenario = 0 % Start scenario at this time insteadScenarioLength = ScenarioLength - FastForwardScenario;InitialSettlingTime = InitialSettlingTime - FastForwardScenario;SimulationLength = InitialSettlingTime + ScenarioLength;

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