如今，汽車行業(yè)已經(jīng)開(kāi)始爭(zhēng)先采用48V混動(dòng)系統(tǒng)。近日，雷諾（Renault）宣布，將于下月進(jìn)入量產(chǎn)的全新2017款風(fēng)景（Scenic）MPV將采用大陸（Continental）公司的低壓“輕”混合技術(shù)。在此之前，奧迪（Audi）也曾宣布旗下2017款SQ7將采用法雷奧（Valeo）的48V系統(tǒng)。此外，梅賽德斯-奔馳（Mercedes-Benz）也在近日宣布，新型六缸和四缸直列發(fā)動(dòng)機(jī)系列也將采用48V子系統(tǒng)。
據(jù)了解，大陸的48V系統(tǒng)將作為一種標(biāo)配，同時(shí)登陸汽油和柴油版的雷諾風(fēng)景混合動(dòng)力多功能車（Scenic Hybrid Assist）。該系統(tǒng)直接將液冷電機(jī)和逆變器集成至電機(jī)殼體之內(nèi)，共同組成啟動(dòng)器發(fā)電機(jī)（ISG）。系統(tǒng)具體位于內(nèi)燃發(fā)動(dòng)機(jī)前端輔機(jī)驅(qū)動(dòng)的一般稱為“P0”的位置，通過(guò)筋帶與曲軸連接。大陸北美公司混合電動(dòng)車工程主管Juergen Wiesenberger表示，系統(tǒng)內(nèi)含一個(gè)5 kW·h的鋰離子電池，電池重約15kg（33lb）。
Wiesenberger告訴《汽車工程》雜志，登陸雷諾對(duì)大陸集團(tuán)龐大的48V計(jì)劃來(lái)說(shuō)，只是冰山一角。大陸集團(tuán)計(jì)劃在未來(lái)幾年內(nèi)向北美、歐洲和中國(guó)市場(chǎng)大量輸送48V系統(tǒng)，同時(shí)登陸汽油和柴油車型。大陸集團(tuán)混合電動(dòng)業(yè)務(wù)部執(zhí)行副總裁Rudolf Stark稱，預(yù)計(jì)到2020年，全球采用48V系統(tǒng)的車輛總數(shù)將達(dá)到400萬(wàn)輛；到2025年，全球約有20%的新車均將配備48V系統(tǒng)。
Stark認(rèn)為，48V系統(tǒng)將成為混合電動(dòng)和純電動(dòng)汽車之間的“過(guò)渡技術(shù)”，為車輛提供額外6到20kW的功率，從而滿足不斷提升的汽車能效需求，并為客戶提供一系列新功能，包括電加熱擋風(fēng)窗、自適應(yīng)懸架系統(tǒng)及電動(dòng)渦輪增壓器等。比較來(lái)看，全混合動(dòng)力系統(tǒng)的功率輸出通常在20-40kW，插電式混合動(dòng)力系統(tǒng)一般則在50-90kW。
Stark也認(rèn)同其他推進(jìn)系統(tǒng)工程師的看法，稱48V系統(tǒng)能夠“以30%的成本，提供其他高功率系統(tǒng)70%的效益。”Stark和Wiesenberger均表示，在同級(jí)別車內(nèi)，與其他非混合動(dòng)力系統(tǒng)相比，大陸的最新48V量產(chǎn)系統(tǒng)已經(jīng)在真實(shí)駕駛環(huán)境下表現(xiàn)出了超過(guò)20%的燃料經(jīng)濟(jì)性提升。
除了大陸集團(tuán)，目前多家一級(jí)供應(yīng)商均在積極敲定ISG和P2型（位于內(nèi)燃機(jī)與變速器之間“P2”位置的電機(jī)）系統(tǒng)的生產(chǎn)合同。2017到2020年間，隨著世界各主要地區(qū)CO2減排規(guī)定越來(lái)越嚴(yán)格，這些系統(tǒng)預(yù)計(jì)也將逐步上市。
Wiesenberger表示，根據(jù)具體規(guī)格不同，大陸的液冷48V ISG系統(tǒng)大約可連續(xù)輸出6 kW的功率和60 N·m的扭矩，安裝體積與12V啟動(dòng)器交流發(fā)電機(jī)相仿。根據(jù)版本不同，ISG系統(tǒng)最高可輸出150 N·m的扭矩。另外，這款48V系統(tǒng)應(yīng)用了模塊化設(shè)計(jì)理念，采用了MOSFET型逆變器。
Wiesenberger表示，該系統(tǒng)可在0.2秒內(nèi)啟動(dòng)車輛內(nèi)燃機(jī)，幾乎比12V啟停系統(tǒng)快一倍。他補(bǔ)充說(shuō)，當(dāng)配合柴油發(fā)動(dòng)機(jī)使用時(shí)，由于電機(jī)可提供額外的扭矩，48V系統(tǒng)在較低轉(zhuǎn)速時(shí)可以將尾氣中的NOx排放降低10%。
P2型48V系統(tǒng)可以獨(dú)立于內(nèi)燃機(jī)運(yùn)行。Wiesenberger表示，大陸與舍弗勒（Schaeffler）聯(lián)合開(kāi)發(fā)的P2型48V系統(tǒng)可為車輛提供50km/h的最高車速。與其他非混動(dòng)型號(hào)相比，節(jié)油表現(xiàn)更是高達(dá)25%。
The industry’s race to deploy 48-V hybrid systems has begun. Renault is the latest OEM to announce incorporation of the “mild” low-voltage hybrid technology, developed and supplied by Continental, in its new 2017 Scenic MPV entering production next month. The news follows Audi’s earlier production announcement of a Valeo-supplied 48-V system in the 2017 SQ7 (http://articles.sae.org/14662 ). Mercedes also recently announced its new inline-six and four-cylinder engine families will include 48-V subsystems.
Conti’s 48-V system will be standard equipment on both gasoline and diesel versions of the Scenic Hybrid Assist model. The system features a liquid-cooled induction motor with inverter integrated into the motor housing comprising the integrated starter-generator (ISG) unit. It is fitted in the so-called “P0 [zero]” position on the combustion engine’s front-end accessory drive, coupled to the crankshaft via a reinforced belt. The system includes a .5 kW·h lithium-ion battery. Total system mass including battery is 15 kg (33 lb), said Juergen Wiesenberger, head of HEV engineering at Continental North America.
The Renault business is the tip of the iceberg for Continental’s 48-V program, Wiesenberger told Automotive Engineering. The company has 48-V production programs in the pipeline for both gasoline and diesel vehicles in North America, Europe and China over the next few years. His colleague Rudolf Stark, executive VP of Conti’s hybrid-electric business unit, forecast about 20% of new vehicles worldwide will be equipped with a 48-V system by 2025, about 4 million of them by 2020.
Stark considers 48-V systems to be a “bridge technology” between current mild HEVs and full EVs, providing 6 to 20 kW to meet the increased power demands of a variety of new vehicle-efficiency and customer-pleasing features including electrically-heated windshields, adaptive suspension systems and electric turbochargers. By comparison, a full hybrid system typically offers 20-40-kW and a plug-in hybrid, 50-90 kW.
Stark echoed other propulsion-system engineers that 48-V systems “provide about 70% of the benefit of higher-power systems for about 30% of the cost.” He and Wiesenberger claim Conti’s latest 48-V production systems have demonstrated up to 20% greater fuel economy in real-world driving, compared with non-hybridized powertrains in similar weight-class vehicles.
Continental is among a number of Tier 1 suppliers that are lining up production contracts for both ISG and P2 (e-motor fitted in the “second” position between the ICE and transmission) types. They are expected to launch within the 2017-2020 timeframe in conjunction with tightening CO2 regulations in the major regions.
Wiesenberger claims that Continental’s liquid-cooled 48-V ISG can, depending on specification, continuously provide 6 kW and 60 N·m (44 lb·ft) roughly within the package space of a 12-V starter alternator. Variants of the ISG are rated up to 150 N·m (110 lb·ft). Conti’s 48-V system is a modular design using a MOSFET (metal-oxide-semiconductor field-effect transistor)-based inverter.
Conti’s 48-V system starts the ICE within 0.2 s—about twice as fast as a 12-V stop-start system, Wiesenberger said. He added that when part of a diesel-hybrid propulsion system, 48-V has demonstrated reduced NOx emissions at lower rpm by up to 10% due to the supplemental torque generated by the e-motor.
P2-type 48-V systems enable independent operation of the combustion engine. According to Wiesenberger, Conti’s P2 system co-developed with Schaeffler allows all-electric driving at up to 31 mph (50 km/h) with a claimed fuel savings of up to 25% greater fuel efficiency than a non-hybridized model.
Author: Lindsay Brooke
Source: SAE Automotive Engineering Magazine
據(jù)了解，大陸的48V系統(tǒng)將作為一種標(biāo)配，同時(shí)登陸汽油和柴油版雷諾風(fēng)景混合動(dòng)力MPV（Scenic Hybrid Assist）。ISG單元位于內(nèi)燃發(fā)動(dòng)機(jī)前端輔機(jī)驅(qū)動(dòng)的所謂的“P0 [零]”位置，其中包括一款5kW·h的鋰離子電池。
大陸集團(tuán)北美混合動(dòng)力工程主管Juergen Wiesenberger表示，該系統(tǒng)可在0.2秒內(nèi)啟動(dòng)車輛內(nèi)燃機(jī)，幾乎比12V啟停系統(tǒng)快一倍，而且還能協(xié)助柴油車型將尾氣中的NOx排放降低最高10%。
大陸集團(tuán)混動(dòng)業(yè)務(wù)執(zhí)行副總裁Rudolf Stark認(rèn)為，48V系統(tǒng)將成為混合電動(dòng)和純電動(dòng)汽車之間的“過(guò)渡技術(shù)”。