%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% % UPDATED APRIL 15, 2010, Tara Chalermsongsak % linearize the Simulink block diagram of the % % FREQUENCY STABILIZATION SERVO % %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% % This gets the linearized model from the simulink model % "psl5.mdl" deg = 180/pi; Modulation_Frequency = 35.5e6; % FSS f_sb in Hz %+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ % Plant Parameters %+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Ref_Cav_Pole = 35e3; % Hz Reference_Cavity = tf(2*pi*Ref_Cav_Pole,... [1 2*pi*Ref_Cav_Pole]); %% Analyzed cavity added, PMC removed Analyzer_Cavity = tf(2*pi*Ref_Cav_Pole,... [1 2*pi*Ref_Cav_Pole]); Photodiode_Pole = 15e6; % New Focus 1811 Photodiode = tf(2*pi*Photodiode_Pole,... [1 2*pi*Photodiode_Pole]); OpticalGain = 0.02e-7; % Watts per Hz Efficiency = 0.8; % Amps per Watt Zrf = 40000; % Tuned Circuit Impedance Grf = 1; % Pre amplifier gain DemodGain = 1/sqrt(2)/2; VoltsPerHz = OpticalGain * Efficiency *... Zrf * Grf * DemodGain; %PiezoActuatorGain = 5e6; % Hz per Volt %PCActuatorGain = 0.001; % Radians per Volt %===================== % Acav path %===================== PDH_box = 1; % this will be replaced later with the measured TF VCO=1; %Hz/V AOM=2; % Hz/Hz %+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ % Ref Path, the signal goes through D980536-D %+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ %============== % D980536-D % The calculation on Mar 31, 2010 in lab book %============== %======================== %signal from PD , ref cav %======================== %===================== %elliptic filter 12MHz %===================== r=50 ; L1= 1.2 *10^-6; C3= 200*10^-12; C4= 47 *10^-12; C5= 200*10^-12; R8= 100; R12= 200; z1= r*tf(1 ,[C3*r 1]); z2= tf([L1 0],[L1*C4 0 1]); z3= tf(R8, [C5*R8 1]); z4 = z2+z3; Elliptic_Filter = z1*z3/(z1+z4); % the filter is specified as 12MHz Ellip, but is seems a bit higher CommonGain1 = R12/R8; % This will be adjustable gain before the signal is sent to % Fast and PC paths %++++++++++++++++++++ %==================== %Fast path, PZT, (to laser) %===================== R51= 1.1 *10^3; R54=2.43*10^3; C55 = 3300 *10^-12; Fast_Gain1=1; %Adj gain Fast1 = (-R54/R51)*tf( 1/(C55*R54), [1 1/(C55*R54)] ); R50= 750; R53= 1.58*10^3; C54 = 0.01 *10^-6; Fast2 = (-R53/R50)*tf( 1/(C54*R53), [1 1/(C54*R53)] ); R49= 3.74 *10^3; R52=15.8 *10^3; R55= 3.74 *10^3; L2= 3.3*10^-3; C46 = 470 *10^-12; C47 = 120 *10^-12; Cs = C46 + C47; R48 = 200; zz = tf( [L2 R48 1/Cs],[1 0] ); % this is a wire before Fast3 Fast3 = -R52/(R49 +R55 + R55*R49/zz); Fast_Filter = Fast_Gain1*Fast1*Fast2*Fast3 ; %total gain from PZT path %==================== %PC path,very fast %==================== %% R17= 1.1 *10^3; R14= 24.9 *10^3; R22= 1.21 *10^3; R23= 150; R27= 15 *10^3; R28= 1 *10^3; R31= 100 *10^3; R32= 20 *10^3; R43= 10 *10^3; R34= 100 *10^3; C13= 47 *10^-9; C18 = 2200 *10^-12; C23 = 10 *10^-9; PC1 = (-R14/R17)*zpk(0,-1/(C13*R17),1)... *tf( 1/(C18*R14), [1 1/(C18*R14) ] ); % PC1 = (R14/(R17 +1/iwC13 ))* (1/ iwC18R14) %This will be corrected, there's another part of 200pF and 100 ohm that I %left out PC2 = (- R27 / R22 )*... zpk(-1/(C23*R23), -1/(C23*(R23 + R27)) ,1); PC12 = PC1*PC2; PC3 = -(R32/R28)*( (PC12 + (R28/R31))/PC12 ); %tf befrom V before R43 / V before R28 z13= tf(1, [1/C13 0] ) ; PC123 = (R32/R31)* ( PC12*(z13 +R31) + R28 )/... ( PC12*z13 + R28 ); %tf from PC 1,2 and 3 before C13 and after R32 %This can be used for TF (Vo/Vi) between TP7 and TP3. PC4 = R34/R43; PC_Filter= PC123*PC4; % total gain from pc path %++++++++++++ %++++++++++++ %++++++++++++ laser_act = 1 ;%Hz/V; %%This will be measured phase_act = 1 ;%rad/V %% This will be measured % On-Screen Parameters %CommonGainSlider = -10; %CommonGain = 10^(CommonGainSlider/20); %FastGainSlider = 9; % FastGain = 10^(FastGainSlider/20); % Makes the State-Space object from the .mdl [A,B,C,D] = linmod('psl5'); warning off fss_sys = ss(A,B,C,D);