ws50529
93 lines
4.5 KiB
Python
Executable File
93 lines
4.5 KiB
Python
Executable File
import numpy as np
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from fastapi import HTTPException
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from scipy import signal
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from .schemas import DesignParams
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from .validation import normalize_coefficients, require_finite, validate_frequency
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def _normalize_dc_gain(b_values, a_values):
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dc_gain = np.sum(b_values) / np.sum(a_values)
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return b_values / dc_gain
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def design_coefficients(params: DesignParams):
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fs_val = require_finite(params.fs, "fs")
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f_type = params.filter_type
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if f_type == "Lowpass (低通)":
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validate_frequency("低通截止頻率", params.lp_fc, fs_val)
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b_new, a_new = signal.butter(params.lp_order, params.lp_fc, btype="low", fs=fs_val)
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elif f_type == "Highpass (高通)":
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validate_frequency("高通截止頻率", params.hp_fc, fs_val)
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b_new, a_new = signal.butter(params.hp_order, params.hp_fc, btype="high", fs=fs_val)
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elif f_type == "Bandpass (帶通)":
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f_low, f_high = params.bp_f_low, params.bp_f_high
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validate_frequency("帶通下截止頻率", f_low, fs_val)
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validate_frequency("帶通上截止頻率", f_high, fs_val)
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if f_low >= f_high:
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raise HTTPException(status_code=400, detail="帶通下截止頻率必須小於上截止頻率")
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b_new, a_new = signal.butter(params.bp_order, [f_low, f_high], btype="bandpass", fs=fs_val)
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elif f_type == "Notch (陷波器)":
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validate_frequency("陷波中心頻率", params.notch_f0, fs_val)
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b_new, a_new = signal.iirnotch(params.notch_f0, params.notch_q, fs=fs_val)
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elif f_type == "1P1Z (一極一零)":
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validate_frequency("1P1Z 零點頻率", params.opoz_fz, fs_val, below_nyquist=False)
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validate_frequency("1P1Z 極點頻率", params.opoz_fp, fs_val, below_nyquist=False)
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b_s = [1.0, 2 * np.pi * params.opoz_fz]
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a_s = [1.0, 2 * np.pi * params.opoz_fp]
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b_new, a_new = signal.bilinear(b_s, a_s, fs=fs_val)
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b_new = _normalize_dc_gain(b_new, a_new)
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elif f_type == "2P1Z (二極一零)":
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validate_frequency("2P1Z 零點頻率", params.tp1z_fz, fs_val, below_nyquist=False)
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validate_frequency("2P1Z 極點頻率 1", params.tp1z_fp1, fs_val, below_nyquist=False)
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validate_frequency("2P1Z 極點頻率 2", params.tp1z_fp2, fs_val, below_nyquist=False)
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w_z = 2 * np.pi * params.tp1z_fz
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w_p1, w_p2 = 2 * np.pi * params.tp1z_fp1, 2 * np.pi * params.tp1z_fp2
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b_s = [1.0, w_z]
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a_s = [1.0, w_p1 + w_p2, w_p1 * w_p2]
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b_new, a_new = signal.bilinear(b_s, a_s, fs=fs_val)
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b_new = _normalize_dc_gain(b_new, a_new)
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elif f_type == "2P2Z (二極二零)":
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validate_frequency("2P2Z 極點頻率 1", params.tptz_fp1, fs_val, below_nyquist=False)
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validate_frequency("2P2Z 極點頻率 2", params.tptz_fp2, fs_val, below_nyquist=False)
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validate_frequency("2P2Z 零點頻率 1", params.tptz_fz1, fs_val, below_nyquist=False)
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validate_frequency("2P2Z 零點頻率 2", params.tptz_fz2, fs_val, below_nyquist=False)
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w_p1, w_p2 = 2 * np.pi * params.tptz_fp1, 2 * np.pi * params.tptz_fp2
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w_z1, w_z2 = 2 * np.pi * params.tptz_fz1, 2 * np.pi * params.tptz_fz2
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b_s = [1.0, w_z1 + w_z2, w_z1 * w_z2]
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a_s = [1.0, w_p1 + w_p2, w_p1 * w_p2]
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b_new, a_new = signal.bilinear(b_s, a_s, fs=fs_val)
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b_new = _normalize_dc_gain(b_new, a_new)
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elif f_type == "PID 控制器":
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ki_term = params.pid_ki / (2.0 * fs_val)
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kd_term = params.pid_kd * fs_val
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b_new = [
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params.pid_kp + ki_term + kd_term,
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-params.pid_kp + ki_term - 2.0 * kd_term,
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kd_term,
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]
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a_new = [1.0, -1.0, 0.0]
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elif f_type == "SOGI-Alpha (帶通)":
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validate_frequency("SOGI 中心頻率", params.sogi_f0, fs_val)
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w0 = 2 * np.pi * params.sogi_f0
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b_s = [params.sogi_k * w0, 0.0]
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a_s = [1.0, params.sogi_k * w0, w0**2]
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b_new, a_new = signal.bilinear(b_s, a_s, fs=fs_val)
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elif f_type == "SOGI-Beta (低通)":
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validate_frequency("SOGI 中心頻率", params.sogi_f0, fs_val)
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w0 = 2 * np.pi * params.sogi_f0
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b_s = [params.sogi_k * (w0**2)]
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a_s = [1.0, params.sogi_k * w0, w0**2]
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b_new, a_new = signal.bilinear(b_s, a_s, fs=fs_val)
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else:
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raise HTTPException(status_code=400, detail="未知的濾波器類型")
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return normalize_coefficients(b_new, a_new)
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def design_response(params: DesignParams):
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b_arr, a_arr = design_coefficients(params)
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return {"b": b_arr.tolist(), "a": a_arr.tolist()}
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