Doing THD calc

measurements.py

@@ -0,0 +1,58 @@
+import numpy as np
+import matplotlib.pyplot as plt
+
+import IIR_filter
+
+import zerocross_meas
+import fundamental_freq_meas
+import fft_meas
+
+
+class measurements(object):
+	"""docstring for fft_meas"""
+	def __init__(self, fs=50e3):
+		# Sample Frequency
+		self.fs = fs
+		# Sample Period
+		self.ts = 1/self.fs
+
+		# Low Pass Filter
+		# fs = Sample Frequency, fc = LP Cutoff Frequency
+		self.LPfilter = IIR_filter.IIR_1_Order_LP(fs=self.fs, fc=200)
+
+
+
+		# Zero Crossing Algorithem
+		# fs = Sample Frequency, fc = LP Cutoff Frequency
+		self.zerocross = zerocross_meas.zerocross_meas()
+
+		# Fundamental Frequency Algorithem
+		# fs = Sample Frequency, tn = Time Period for calculations
+		self.base_freq = fundamental_freq_meas.fundamental_freq_meas(fs=self.fs, tn=1)
+
+		# FFT Algorithem
+		# fs = Sample Frequency, tn = Time Period for calculations
+		# 61000-4-7 says 200ms
+		# 10-cycles for 50Hz
+		# 12-cycles for 60Hz
+		self.fft = fft_meas.fft_meas(fs=self.fs, tn=0.2)
+
+
+	def Interupt(self, y):
+
+		# Filter Input
+		y_hat = self.LPfilter.step(y)
+		# Zerocross detection (self.zerocross.flag)
+		self.zerocross.detect(y_hat)
+		# Calculate the Fundamental frequency (self.base_freq.freq)
+		self.base_freq.step(y_hat, self.zerocross.flag)
+		# Calculate the FFT of the signal
+		self.fft.step(y, self.base_freq.freq, unit="I")
+
+
+	def print(self):
+		print(self.base_freq.freq)
+
+	def plot(self):
+		self.fft.plot_Y_H()
+