voc.corr {SunsVoc}

Correct Voc to certain reference conditions, used internally in piv_iv_week function.

Description

This method uses a physical model to correct Voc to certain reference conditions. Since indoor Suns-Voc is conducted at a steady 25C, a correction on the outdoor readings is necessary for meaningful comparison.

Usage

voc.corr(df)

Arguments

df

A dataframe time series data with columns of voc, lnSun and modt, the dataframe is converted from the request input dataframe like df_wbw by the piv_iv_week function before using voc_corr function.

Value

returns a list object of Voc model.

Examples

df <- read_df_raw(df_wbw,0.02,7)
# subset data to first period
df_slice <- dplyr::filter(df, df$n_period == 1)
N_c <- 60 # true of the example data. N_c is the number of cells in series

df_slice <- dplyr::mutate(df_slice, T_K = .data$modt + 273.15,
lnSun = 1.38e-23/1.6e-19 * N_c * .data$T_K * log(.data$isc),
isc2 = .data$isc^2,
T_lnIsc2 = .data$T_K * .data$lnSun * log(.data$isc),
rs = as.numeric(.data$rs),
expVoc = exp(-.data$voc/.data$T_K) / .data$isc,
I0 = (N_c * 1.38e-23 * .data$T_K) / (1.6e-19 * .data$isc))
voc_mod <- voc.corr(df_slice)