TTT4260/D2/Grafer/CapDiode.py

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Python
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2021-04-25 18:18:10 +02:00
#!/usr/bin/env python3
# -*- coding: utf-8 -*-
"""
Created on Fri Apr 26 00:50:35 2019
@author: oyvind
"""
import math
import numpy as np
import matplotlib.pyplot as plt
# Name for the saved graph
filename = "SimuleringPy"
#RPM to simulate
RPM = 40000
#RPM to calculate tau
tauRPM = 40000
# Forward voltage of the diode
forwardVoltage = 0.7
# Threshold voltage of the transistor
thresholdVoltage = 2
# Upper voltage of the pulsetrain
upperVoltage = 5
# How many cycles you want it to run
cycles = 5
# The resolution of each cycle
resolution = 2000
# Converting from RPM to Hz and period in seconds and milliseconds
def RPMtoPeriod(rpm):
Hz = rpm / 60.0
period = 1 / Hz
periodmS = period * 10**3
return periodmS
periodmS = RPMtoPeriod(RPM)
print("Period in ms: " + str(periodmS))
# Calculates the tau based on the period, and the different voltages
def CalculateTau():
# Calculate the roots of the tau-equation
roots = np.roots([forwardVoltage, -upperVoltage, upperVoltage - thresholdVoltage])
# Calculate the possible taus
taus = -(RPMtoPeriod(tauRPM)) / (2 * np.log(roots))
print(taus)
# Discard the non-real tau
if taus[0] > taus[1] and taus[0] > 0:
return taus[0]
return taus[1]
# Just creates a pulsetrain with some voltage and duty-cycle
def GeneratePulsetrain(voltage = 5, dutyCycle = 0.5):
pulseTrain = []
for i in range(cycles):
for i in range(round(resolution * 2 * dutyCycle)):
pulseTrain.append(voltage)
for i in range(round(resolution * 2 * (1 - dutyCycle))):
pulseTrain.append(0)
return pulseTrain
# Generate the time-signatures from the number of cycles, the resolution and
# the periodtime. result in milliseconds
def GenerateTime():
times = []
for t in range(cycles * resolution * 2):
times.append(periodmS * t / (resolution * 2))
return times
def OutVoltage(wave, times):
cP = wave[0] # Start voltage-supply
v0 = 0 # Start voltage
cT = 0 #Start time
volt = []
for p in range(len(wave)):
# If the voltage-supply changes, recalculate startvalues
if wave[p] != cP:
v0 = volt[-1] # New start voltage, uses the last voltage calculated
if wave[p] == 0:
v0 = forwardVoltage
cP = wave[p] # Variable so the array is not accessed.
cT = times[p] # Offset time for each period
# Calculate the outgoing voltage over the CAPACITOR with the start values
volt.append(cP + (v0 - cP) * math.exp(-(times[p] - cT) / tau ))
return volt
def GenerateThreshLine(times):
thresh = []
for i in times:
thresh.append(thresholdVoltage)
return thresh
# Calculate Tau
tau = CalculateTau()
print("Tau in ms: " + str(tau))
# Generate all the lists of pulsetrain and time-signatures
time = GenerateTime()
pulse = GeneratePulsetrain(upperVoltage)
threshLine = GenerateThreshLine(time)
# Simulate the outgoing voltage
voltage = OutVoltage(pulse, time)
plt.figure(figsize=(12,5))
plt.plot(time, pulse)
plt.plot(time, voltage)
plt.plot(time, threshLine, 'k--')
plt.title("Spenningsutvikling ved " + str(RPM) + " RPM. Grensefrekvens er " +
str(tauRPM) + " RPM.")
plt.xlabel("Tid [ms]")
plt.ylabel("Spenning [V]")
plt.legend(["Pulstog, " + r'$v_1$', "Utgående spenning, " + r'$v_2$', "Terskelspenning, " + r'$V_T$'], loc="upper right")
plt.savefig(filename + ".png", dpi = 300)
plt.show()