《TESLA小知識》解密EPA「調整係數」(derating factor)

●EPA有多種測試工況,前文只提到其中2種
《TESLA小知識》淺談EPA里程測試
●車廠可選擇加跑其他3種工況,以獲得較佳的調整係數(一般是0.7)
EPA allows automakers the option to run three additional drive cycles and use those results to earn a more favorable adjustment factor.

這段話還沒完全弄清楚,只提到「做了五工況法(5-cycle)就有機會獲得較佳的調整係數」,所謂"較佳"是如何決定?可以多0.03還是0.05?

查閱多份EPA報告後,終於在一份舊報告找到答案,算法是「新調整係數=兩工況法電耗÷五工況法電耗」,換算之後,其實就是拿五工況法的測試結果當作EPA宣告里程

《TESLA小知識》解密EPA「調整係數」(derating factor)

舉例來說,兩工況法跑出500英里,EPA必須宣告500*0.7=350英里,此時可以跑跑看更複雜(較接近實際狀況?)的五工況法,假設跑出370英里,就可以宣告370英里,假設只跑出330英里,就用原本的350英里

延伸閱讀:
《TESLA專題》從EPA測試報告分析21年式M3LR里程提升來源
《TESLA小知識》如何回推EPA里程「調整係數」
《TESLA小知識》淺談EPA里程測試
《TESLA知識家 #10》分享總整理 (持續更新)

來源:https://iaspub.epa.gov/otaqpub/display_file.jsp?docid=49396&flag=1
https://fb.me/TeslaHere|TESLA知識家
是這樣的沒有錯,直接用5cycle tests 的結果不用調整係數。
EPA在2017年就發了白皮書針對電動車里程跟排放測量方法
做明確規範:
 
EPA test method for EV and PHEV
 
針對BEV的部分:
 
EPA currently allows fuel economy, energy consumption, CO2 values, and range values listed on the
FE Label (window sticker) for electric vehicles to be adjusted using one of the following methods:
 
by multiplying city/highway fuel economy and range values by 0.7 and dividing city/highway energy consumption and CO2 values by 0.7;
using the derived 5-cycle method described in 40 CFR 600.210-12(a)(2) and EPA guidance letter CD-15-15, June 22, 2015 (available at https://www3.epa.gov/otaq/cert/dearmfr/dearmfr.htm);
 using a method which is equivalent to the vehicle specific 5-cycle method described in 40 CFR 600.210-12(a)(1) (with prior EPA approval) such as the method provided in Appendix B of SAE J1634 July 2017
Recommended Practice;
 using adjustment factors which are based on in-use data (with prior EPA approval).
Currently, most EVs use the first or third method (the 0.7 factor).
 
所以用5 cycle tests 的結果反推2 cycle的derating factor是否灌水
沒太大意義,頂多說明EPA定的0.7是過於樂觀或悲觀,畢竟5 cycle
tests的結果更接近真實的使用情況(多了高速130km/h max、
零下低溫測試、行駛時開AC)。
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