外媒：逆變器設計缺陷導致特斯拉突然意外加速

最近，外媒carscoops發了一篇報道。報道指出，逆變器的設計缺陷可能導致Model 3(參數|詢價)出現意外、突然的加速。

我概況了一下，文章的核心觀點有這幾個：

1、 逆變器設計缺陷會讓車輛把12伏電池隨機出現的電壓峰值，誤當作加速踏板踩下的信號，進而導致車輛意外、突然的加速。但實際上，駕駛員并沒有踩加速踏板。

(相關資料圖)

2、這種誤操作不會被車輛當作錯誤記錄下來。導致的結果是：車輛記載的數據顯示，當時駕駛員踩下了加速踏板，而駕駛員稱自己沒有踩加速踏板。（車輛后臺數據和駕駛員各執一詞的原因就在這里嗎？）

3、這種設計缺陷具有偽裝性。它導致車輛在出現突然意外加速時，從表面看上去，是駕駛員踩下了加速踏板，但駕駛員并沒有踩加速踏板。

4、 一些汽車發燒友拆解特斯拉，發現了逆變器的這個問題，然后把信息提供給研究者。研究者據此得出了結論。（不得不贊嘆，這些汽車發燒友很厲害）

5、 針對特斯拉的投訴案例顯示，在低速行駛或打方向盤轉彎時，會偶爾出現這種意外突然加速。

6、目前NATHSA正在重新調查這個新發現，目前沒有定論。也沒有讓特斯拉采取召回或其它措施。

點評：這的確是一個非常嶄新和重要的發現，為某些特斯拉突然加速事故的原因提供了新的思路和視角。

這個結論是不是正確，還有待NTHSA調查結果。如果這個結論坐實。那么，特斯拉可能面臨大事。之前全球范圍內包括中國市場，出現的那些特斯拉車輛失控案例，那些駕駛員和特斯拉各執一詞的爭論和官司，可能就有了新的證據，新的解讀，甚至新的判決。

總之，特斯拉車輛失控案例，是駕駛員的問題還是車的問題，可能會有新的答案。

附：carscoops外文翻譯及原文：僅供參考

聯邦調查局評估請愿書：特斯拉Model3的設計缺陷可能導致意外加速。

NHTSA正在調查一項請愿書：位于特斯拉model 3控制系統深處的電壓峰值，可能引發車輛錯誤地讀到加速信號，即使駕駛員沒有踩加速踏板。

一位研究者BELT博士稱，自己已經找到了新證據，證據指明model 3的逆變器設計，是引發突然、意外加速的原因。

作為向NHTSA提交的請愿書的一部分，他們進一步指出：這個缺陷還會導致表面看上去，駕駛員已經踩了加速踏板，即使當時駕駛員并沒有踩加速踏板。

聯邦管理者第一次調查這個事件是2019年，當時，他們收到Brian Sparks的請愿書，他要求強制特斯拉召回2013-2019年期間生產的所有Model S(參數|詢價),X和3。

但是，評估請愿書后，ODI（政府缺陷調查辦公室）最終支持了特斯拉的結論。即請愿書提到的232個案例中，根據當時事故車輛收集的數據顯示，駕駛員都踩了加速踏板。因此，2021年，ODI辦公室否定了請愿書。

但這個結論并不適用所有人。尤其是在至少一個案例中，據駕駛員稱，當時他們還在車外，車輛就加速了。現在，BELT博士基于新發現的信息，已經提交了一個新的申請，要求ODI重新審查這項請愿書。

汽車發燒友收集的信息為BELT博士的指控提供了支持。這些發燒友拆解了特斯拉車型，想用它的電動總成做電動汽車轉換或其他用途。在拆解中，他們對電動車廠的逆變器和電路板設計積累了新的見解。

在model 3上，BELT博士聲稱，在極少數案例中，逆變器的設計缺陷可能導致車輛把隨機出現的電壓峰值誤認為踩下了加速踏板。因為model 3的逆變器采用了單個1.65伏的校準信號來檢查4個ADC（模擬信號-數字信號轉換器，也就是把加速踏板位置的信息轉換為電子信號，然后給車輛讀取的零部件）。

在一些案例中，尤其是當車輛慢速行駛，或者，例如方向盤需要更多電力時，車載12伏電池的電耗會在系統中引發一個相對較高的（電壓）峰值，導致逆變器誤認為加速踏板已經被踩下，進而導致車輛突然、意外的加速。

至少，這是belt的理論。他說，一個電壓峰值（持續幾微秒）和車輛進行ADC檢查時（也持續幾微秒）必須同時出現，才會出現這種情況，這是極其罕見的。但是，根據他的評估，這種罕見數量和2013-2019年期間發生的特斯拉突然加速案例數量是一致的。

BELT博士還稱，因為缺陷的性質---逆變器把電壓峰值誤解釋為加速踏板信號輸入---這個行為并不會被當作錯誤記錄下來。結果，盡管駕駛員說他們沒有踩加速踏板，但車輛數據并不認同駕駛員說法。這也解釋了為什么2019年ODI辦公室否認了車主的請愿。目前，BELT博士的指控是針對 model 3的，它的逆變器設計和model S和X不同。但是，他明確補充說，這些車型也會產生類似問題。

現在，ODI缺陷調查辦公室將調查這份報告，看看是否同意這些發現。近期發給NHESA的指控，要求NHTSA調查特斯拉的意外加速。另外有人認為，某些車輛缺少剎車聯鎖系統，是特斯拉意外加速的原因之一。在現階段，特斯拉還沒有被要求采取措施。

附：外媒報道原文:

Feds Assess Allegations That Design Flaw In Tesla Model 3 Can Lead To Unintended Acceleration.

NHTSA is looking into allegations that a voltage spike deep within the Tesla Model 3"s control systems could cause the car to mistakenly read an accelerator input, even when none has occurred.

by Sebastien Bell

July 4, 2023 at 16:40

A researcher claims to have found new evidence pointing to the design of the Tesla Model 3’s inverter as the cause of a fault that could lead to sudden, unintended acceleration. As part of a petition filed with the National Highway Traffic Safety Administration, they further allege that the fault could make it look like the driver has pressed the accelerator pedal, even if they did not.

The federal regulator first looked into the merits of this issue in 2019, after receiving a petition from one Brian Sparks, who requested that it compel Tesla to recall every Model S, X, and 3 made between 2013 and that year.

However, upon evaluating the claims, the administration’s Office of Defect Investigations (ODI) agreed with Tesla that in almost all of the 232 instances referred to in the original petition, the driver had pressed the accelerator, based on data collected by the vehicles in question. In 2021, it denied the petition.

That did not sit right with everyone, since in at least one case, the driver claimed they were outside the vehicle when it accelerated. Now, a new request has been filed by Dr. Ronald A. Belt based on new information, asking the ODI to reexamine the petition.Read: Tesla Might Have An Unintended Acceleration Issue As Regulators Investigate Over 120 Claims.

Belt bases his new allegations on information gathered by enthusiasts who are tearing down Teslas in order to use their powertrains for EV conversions and other purposes. These have garnered new insights into the design of the automaker’s inverters and circuit boards.

In the Tesla Model 3, Belt alleges that a fault in the design can lead to the vehicle mistaking a random voltage spike for a pedal application in extremely rare cases. That’s because the Model 3’s inverter uses a single 1.65-volt calibration signal to check in on four ADCs (analog-to-digital converters, or the part that converts pedal position into an electric signal for the car to read, in this case).

In some instances, especially when the vehicle is driving slowly and, for example, the power steering requires more power, the draw on the 12-volt battery can cause a relatively enormous spike in the system, leading the inverter to infer that the accelerator pedal has been pressed, and leading to sudden unintended acceleration.

At least, that’s the theory proposed by Belt, who says that a spike (which lasts microseconds) must occur while the car is performing an ADC check (which also lasts microseconds), making it exceedingly rare. However, by his estimates, the rarity of the event aligns with the 200-or-so incidents reported between 2013 and 2019.He also claims that due to the nature of the fault – the inverter misinterpreting a voltage spike as a throttle input – it doesn’t get logged as an error. As a result, despite owners reporting that their foot wasn’t on the pedal, the vehicle data disagrees with them, which may explain why the ODI first denied the petition.

So far, Belt’s allegations are directed at the Model 3, whose inverter design is different than the one found on the?Model S and X. However, he is clear to add that these vehicles may also be subject to similar errors.

Now, the ODI will look into this report to see whether or not it agrees with its findings. Just the latest petition sent to NHTSA asking it to look into unintended acceleration in Teslas, others have proposed the lack of a brake interlock system in certain vehicles as a cause of the phenomenon. At this moment, no action is required from the automaker.