从Excel工作表创建CSV时如何绕过“PHPExcel_Calculation_Exception”？

Question

<?php
require_once 'PHPExcel/PHPExcel.php';


$downloadedFileName = "sheet.xls";

set_time_limit(0);

if (file_exists($downloadedFileName)) {
    unlink($downloadedFileName);
}
$spreadsheet_url="Google Sheet with 4 tabs URL goes here";

file_put_contents($downloadedFileName,file_get_contents($spreadsheet_url));


if (file_exists($downloadedFileName)) {

    $inputFileType = PHPExcel_IOFactory::identify($downloadedFileName);

    $objReader = PHPExcel_IOFactory::createReader($inputFileType);
    $objPHPExcelReader = $objReader->load($downloadedFileName);

    $loadedSheetNames = $objPHPExcelReader->getSheetNames();

    $objWriter = PHPExcel_IOFactory::createWriter($objPHPExcelReader, 'CSV');

    foreach($loadedSheetNames as $sheetIndex => $loadedSheetName) {
        $objWriter->setSheetIndex($sheetIndex);
        $objWriter->save($loadedSheetName.'.csv');
    }   
}
else{
        echo "File not found";
    }

?>

This gives an error :

Fatal error: Uncaught exception 'PHPExcel_Calculation_Exception' with
message 'ArticulosQueNoSonKARE!A1 -> internal error' in 
D:\xampp\htdocs\xlstocsv\PHPExcel\PHPExcel\Cell.php:291 Stack trace: #0 
D:\xampp\htdocs\xlstocsv\PHPExcel\PHPExcel\Worksheet.php(2492): PHPExcel_Cell-
>getCalculatedValue() #1 
D:\xampp\htdocs\xlstocsv\PHPExcel\PHPExcel\Writer\CSV.php(142): 
PHPExcel_Worksheet->rangeToArray('A1:M1', '', true) #2 
D:\xampp\htdocs\xlstocsv\index.php(30): PHPExcel_Writer_CSV-
>save('ArticulosQueNoS...') #3 {main} thrown in 
D:\xampp\htdocs\xlstocsv\PHPExcel\PHPExcel\Cell.php on line 291

I can figureout that its because of some cells containing formulas..But I need to take that value from the cell. I have no edit permission to modify and edit those cells. I need this script running as a chrone job.. Ihave done with the other part. Please help. Thank you