bsrn.modeling.separation.brl_separation#

bsrn.modeling.separation.brl_separation(times, ghi, lat, lon, min_mu0=0.065, max_zenith=87.0)[source]#

BRL irradiance separation [1]: diffuse fraction $k$ from logistic function of $k_t$, AST, $alpha$, $K_t$, $psi$. BRL 辐照分离：由 $k_t$、AST、$alpha$、$K_t$、$psi$ 的逻辑回归函数得散射分数 $k$。

$k = 1 / (1 + exp(-5.38 + 6.63 k_t + 0.006,text{AST} - 0.007,alpha + 1.75 K_t + 1.31 psi))$. $psi$ at sunrise = $k_{t+1}$, at sunset = $k_{t-1}$, else $(k_{t-1}+k_{t+1})/2$. $K_t$ = daily clearness index. 日出时 $psi = k_{t+1}$，日落时 $psi = k_{t-1}$，否则为 $(k_{t-1}+k_{t+1})/2$。$K_t$ = 日晴朗指数。

Parameters:

  • times (pd.DatetimeIndex) – Timestamps. 时间戳。

  • ghi (array-like) – Global horizontal irradiance. [W/m^2] 水平总辐照度。[瓦/平方米]

  • lat (float) – Latitude. [degrees] 纬度。[度]

  • lon (float) – Longitude. [degrees] 经度。[度]

  • min_mu0 (float, default 0.065) – Minimum $mu_0$ when computing $k_t$. 计算 $k_t$ 时 $mu_0$ 最小值。

  • max_zenith (float, default 87.0) – Maximum zenith for valid BNI; beyond this BNI is set to 0. [degrees] BNI 有效的天顶角上限；超过则 BNI 置 0。[度]

Returns:

out – DataFrame with index=times and columns k, dhi, bni (modeled). 索引为 times、列为 k/dhi/bni（模型结果）的 DataFrame。

Return type:

pd.DataFrame

Raises:

ValueError – Propagated from _get_solar_and_kt() if times or ghi are invalid. 由 _get_solar_and_kt() 在 times 或 ghi 无效时抛出。

References