BorgWarner’s
Integrated Drive Module (iDM)
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BorgWarner’s Integrated Drive Module (iDM)
BorgWarner’s integrated drive module (iDM) combines power electronics, electric motorand mechanical components within one single eAxle unit.
Matthew Vanderlip, iDM Solutions Architect & Manager, System Strategy & Platform Engineerings

Introduction

Developing and improving the solution

With an ever­growing trend towards electric pro­With its capability to design, test and manufac­

pulsion there is also an increasing demand forture complete electrification systems for passen­

flexible electrification components that meet theger cars as well as commercial vehicles,

requirements of different vehicle architectures.

BorgWarner can perform motor, power electron­

By permanently enhancing the portfolio throughics, drivetrain, and software design in­house todevelopment of innovative technologies and ac­

develop fully optimized and highly integrated

quisitions that contribute to the company’s exper­

system solutions for a wide range of applications.

tise,

BorgWarnerhas

positioned

itselftoaccelerate its growth in electrification productsBorgWarner’s first iDM system platform, theand drivetrain solutions (Fig. 1).

iDM200 developed in 2018, utilizes the 200mm
outer diameter hairpin motor HVH200 with an

The latest generation of BorgWarner’s integrat­interior permanent magnet (IPM) rotor, which

ed Drive Module (iDM), for example, is easy to

was designed to target performance require­

fit, tested and correlated, and it supports auto­

ments ranging from 80 to 150kW. The next step

makers in their design of efficient hybrid andwas the development of a new iDM system forelectric vehicles. Based on common architec­

larger, more powerful vehicle applications. Theture, it combines power electronics, electric mo­

iDM220 platform is intended for operations intor, and mechanical components within one

the 150 to 250kW power range when utilized insingle eAxle unit enabling the fast development

400V systems, or up to 500kW in 800V form.

of primary and secondary propulsion applications

For this, a new HVH220 (220mm outside dia­and helping manufacturers to comply with strictmeter) machine was designed. The newsustainability demands and emissions rules.

HVH220 concept right­sizes the conductors toFig. 1: Building capability through organic growth and strategic acquisitions.
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bring the current density back to an ideal range

gearbox oil to cool the motor can improve heatto match the iDM220’s innovative oil coolingtransfer and therefore the total heat rejection ofstrategy. This enabled an average power con­the system, thus increasing its performance.

sumption reduction of 250W over the WLTC

However, an electric pump is needed to achieve(World harmonized Light­duty vehicles Test

the flow rates required for effective oil cooling,Procedure) drive cycle, representing a 22% im­

which adds to the system cost and complexity.

provement.

Also, the oil is now being used as a sink formore heat therefore an oil cooler is often added

Cooling system a question of perfor­
mance requirements

But the cost of these components can be bal­

Another important aspect of the iDM system de­anced against savings on the electric machine.

velopment is its cooling design as it can be le­Furthermore, oil cooling solutions include novel

veraged to reduce overall costs by allowing thedesign features to minimize system losses

use of smaller, power­dense motors and elec­

through the elimination of high­speed seals andtronics. System cooling is critical to extracting

gearset churning. This approach also utilizes

the most performance out of the iDM while keep­

direct rotor oil cooling to extract heat from theing cost under control. Therefore, BorgWarnercore of the electric motor thus enabling higher

has developed both water­cooled and oil­cooled

torque and power density. These benefits leadsolutions.

to vehicle­level improvements in range or op­

to keep oil temperatures within operating range.

portunities to reduce battery size resulting in a
Lowest system costs – while still complying

net benefit.

with performance and package requirements –are achieved by combining the inverter andFlexible platform

motor cooling circuit. Typically, the motor is part

By using a building­block approach, each iDMof the water ethylene­glycol (WEG) circuit after

system is designed to be flexible in terms of its

the power electronics and cooled via a water

motor winding configuration and stack length,

jacket which encircles the stator. This coolingpower module selection, gear ratio and cooling.

approach is limited by the surface area of theThis allows solutions to match customer per­stator’s outer diameter, relying on conduction

formance and packaging needs without havingfrom the heat source through the stator lamina­

to start from a blank sheet, resulting in fastertions to the WEG mixture.

execution and reduced cost. In addition to thebase functionalities, system add­ons have been

When a higher performance is requested, di­developed and can be optionally integrated in­rect oil cooling becomes a more interesting so­

cluding park, disconnect and torque­vectoringlution for thermal management. Utilizing thesystems.

Fig. 2: 150kW iDM220 variant with B­sample hardware completed in 2021.
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Electronics portfolio expansion

with the appropriate Viper power module andWith the acquisition of Delphi Technologies in

integrating it into a gearbox utilizing a low­loss

2020, BorgWarner has strengthened its position

parallel layshaft gear reduction with a high ef­

in electrification by expanding its product port­

ficiency oil cooling and lubrication strategy sys­

folio. Among these new technologies, the Vipertem, designers are able to reduce the averagefamily of power devices enable significant ad­

WLTP system power consumption by nearlyvances in BorgWarner’s system development

700W at 60°C. The combination balances sys­

capability. The Viper silicon or silicon carbide

tem performance as well as costs and allowed

versions offer system designers a solution toto successfully build and deliver the first twocover nearly all power levels in both 400V andsystem variants of BorgWarner’s new iDM220

800V systems. The devices take advantage ofdrive unit. The first system with a peak power

dual­sided cooling to maximize silicon utilization.

of 170kW and the second system with a peakDual­sided cooling enables up to 50% reduction

output of 225kW.

in semiconductor area for the same perfor­
mance. Viper modules also eliminate the need

NVH improvements

for wire bonds, which improves product yield

With performance targets achieved as describedand reliability. The power modules are physi­

above, specific tools were developed and im­cally the same size, which enables interchange­

plemented into the design, analysis, and testing

ability within a given packaging space. This al­processes to optimize features crucial for thelows system solutions to be developed using

NVH behavior. Thus, lightweight design object­common building­blocks that can be tailored toives could be met while housing deflection andmatch the required system performance. Among

dynamics were improved at the same time. Atthe Viper product family are SiC MOSFETS withthe transmission level, unique design solutions

both 750V and 1200V ratings. These devices

securing gear strength and durability simulta­

enable over 50% inverter loss reduction com­neously minimize gear mesh transmission errors

pared to their Silicon IGBT counterparts for thosefor better NVH. Furthermore, the design processapplications demanding the highest efficiency.

resulted in an optimization of electromagnetic
torque ripple in the e­machine and reduced ra­

System integration

dial forces along with enhanced performance in

By developing the new IPM motor solution withtotal output torque and efficiency.

a 220mm outside diameter, combining thatFig. 3: BorgWarner expands its iDM platform offerings.
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Summary
By integrating a state­of­the­art transmission
along with electric motor and custom powerelectronics, BorgWarner’s iDM can support theautomotive industry in its development of clean­er and more efficient passenger cars and com­
mercial vehicles. The modular approach tosystem integration and development meansthat BorgWarner can offer customers a solutionthat will fit nearly any vehicle need, providing
compact,

lightweight,andefficientcom­

ponents. Each application can draw from thesub­system portfolio to be customized whilestill using tested building blocks to reduce cost,risk, and time­to­market. The iDM is an innova­
tive solution that helps automakers reduce
their electric vehicles’ energy consumption andincrease pure electric reach per battery charge.

Contact
Email: technology@borgwarner.com
For more information please visit
borgwarner.com

BorgWarner Knowledge Library 20214