The 7th generation ACS motor controllers

AC Superdrive (ACS) is a family of inverters/motor controllers with power levels from 5 to 50kVA , designed for nominal voltages between 24V and 80V. The ACS is developed with traction, hydraulic pump and generator applications in mind which makes it an ideal choice for most battery-powered electric vehicles.

The 7th generation ACS features very high power density. The logic platform, which is common to the entire power electronics range of Inmotion, offers unparalleled flexibility in software customization, as well as adherence to demanding functional safety requirements.

All ACS feature CAN bus communication and have extended I/O option for standalone operation, or to facilitate distribution of vehicle control and I/O functionality in an overall system.

Some models are available as dual (AC + AC) or combi controllers (AC traction + DC pump).

Some models in the GEN7 Family are still in development, but all models are available as prototypes for evaluation and testing.

  • Outstanding quality and reliability, achieved through superior design and world class manufacturing processes.
  • Rugged design suitable for the demanding environment of electric vehicles. Protected against ingress of dust and water according to IP65.
  • Powerful MCU with an efficient operating system capable of parallel execution of motor control as well as customized vehicle control tasks.
  • Firmware with built-in standard functionality for common traction, generator and pump applications.
  • Software quality assured through development and review processes designed for Automotive SPICE® and ISO13849-1 compliance.
  • I/O version available for standalone operation or for distributed system I/O.
  • Industry standard CANopen and J1939 for reliable communication in a vehicle system.
  • Control of AC induction, AC synchronous, BLDC, and synchronous reluctance machines.
  • Selected models available as dual (AC + AC) or combi (AC + DC) controllers.
  • Dual MCU's and dual feedback channels for redundant cross monitoring and supervision, allowing ISO13849-1, category 3 implementation of safety functions up to PL=d.
  • State of the art vector control for optimal efficiency throughout the full speed range.
  • Auto-tuning of motor parameters for rapid commissioning of inverters into an existing vehicle.
  • Extensive and powerful event handling and data logging to simplify troubleshooting and minimize vehicle down time.


Motor type Induction AC, Synchronous AC, Brushless DC, Synchronous Reluctance
Communication CAN (CANopen, J1939, CANtalk)
Switching frequency 4, 8, 12, 16 kHz (parameterized)
Operating stator frequency 0-599 Hz
Control mode Speed (rpm), Current (ARMS), Torque (Nm), or Voltage (VDC)
Connector AMP SEAL 23pin or 35pin
Operating temperature -40 °C to 55 °C (-40 °F to 131 °F)
Storage temperature -40 °C to 70 °C (-40 °F to 150 °F) at ambient humidity of 95%
Protection class IP65
Standards UL583, EN1175-1 (decl. of incorporation acc. 2006/42/EC and 2014/30/EU), EN12895


Model Nom. DC supply voltage Rated RMS current(S2, 2min) Rated RMS current(S2, 1h) Rated power(S2, 2min) Rated power(S2, 1h)

ACS S (also available as combi controller)

ACS24S35 24 V 350 A 150 A 10.3 kVA 4.4 kVA
ACS36S35 36 V 350 A 150 A 15.4 kVA 6.6 kVA
ACS48S28 48 V 280 A 120 A 16.5 kVA 7.1 kVA

 ACS M (also available as dual inverter)

ACS24M55 24 V 550 A 275 A 16.2 kVA 8.1 kVA
ACS36M45 36 V 450 A 225 A 19.8 kVA 9.9 kVA
ACS36M55 550 A 275 A 24.2 kVA 12.1 kVA
ACS48M35 48 V 350 A 175 A 20.6 kVA 10.3 kVA
ACS48M45 450 A 225 A 26.5 kVA 13.2 kVA
ACS48M55 550 A 275 A 32.3 kVA 16.2 kVA
ACS80M23 80 V 230 A 115 A 22.5 kVA 11.3 kVA
ACS80M35 350 A 175 A 34.3 kVA 17.1 kVA
ACS80M40 400 A 200 A 39.2 kVA 19.6 kVA


 ACS36L70 36 V  700 A 350 A 30.9 kVA 15.4 kVA
ACS36L90 900 A 450 A 39.7 kVA 19.8 kVA
ACS48L70 48 V 700 A 350 A 41.2 kVA 20.6 kVA
ACS48L90 900 A 450 A 52.9 kVA 26.5 kVA
ACS80L50 80 V 500 A 250 A 49.0 kVA 24.5 kVA
ACS80L60 600 A 300 A 58.8 kVA 29.4 kVA
ACS80L70 700 A 350 A 68.6 kVA 34.3 kVA



ACS GEN7 is available in different sizes, depending on available power and number of axles controlled, as described in table below.

Model S S--C M M--D L
Multi axle - Combi - Dual -
Link to picture
Footprint 150 x 200 mm 200 x 150 mm 200 x 275 mm 200 x 235 mm
Max power (peak/cont) 16.5/7.1 kVA 39.2/19.6 kVA 68.6/34.3 kVA
Heat sink options C, Y, T C, Y, T, (F) C, Y C, Y, (F)
Power terminal options T (M6) T, S (M8) T, S (M8) T, S (M8)
I/O options 35P 23P, 35P 35P-D 23P, 35P

Heat sink options

In order to facilitate cost efficient mounting options for a variety of vehicle designs, there are several different heat sink options for both forced air cooling and conduction cooling (finned and flat heat sinks respectively). The table below outlines the heat sink options.

ACS GEN6 backwards compatibility
The "F" type heat sink is only recommended for customers that need the ACS GEN7 to be backwards compatible to systems with ACS GEN6. The F profile for the "L" size drive, F(L) differs from the F profile for the "M" size drive, F(M).

Heat sink version C Y T F(M) F(L)
Type Flat Fin Fin Fin Fin
Width 200 mm 200 mm 150 mm 200 mm 204 mm
Profile C_HS Y_HS T_HS F_HS

Power terminal options

Power terminals are normally a threaded hole (T) to facilitate mounting of power cables with screws. Optionally most models can be fitted with studs (S) to allow mounting power cables with nuts.

I/O options

ACS GEN7 comes with an option of I/O to optimally suit most applications. The 23 pin interface (23P) is optimized for slave units in a CAN network, with limited I/O capacity. The 35 pin interface (35P) features a larger number of I/O to be used by the application software for standalone operation, vehicle control, or as distributed I/O in a vehicle network. The dual inverter I/O (35P-D) requires more motor interface pins and is thus slightly different. Below is an outline of the various I/O options of ACS GEN7.

I/O version 23P 35P 35P-D
Dedicated HW ID 2 - -
Multifunction I/O* 3 5 5
Digital inputs - 9 5
Analog inputs - 2 -
High side in/out 1 1 1
Sensor supply 1 2 2
Current control output 2 2 4
PWM control output - 2 -
On/off output - 2 -
CAN** 2 1 2
Motor temp 1 1 2

* Multifunction I/O can be used as motor feedback, analog in, or digital in. Motor feedback supported is encoder, UVW (6-step), analog sin/cos.

** CAN interface consists of CAN_HIGH, CAN_LOW and CAN_GND. The 23P and 35P-D versions have two of each pin to facilitate daisy-chaining in a network. Additionally all inverters have a CAN_120 pin that serves to terminate the CAN bus if a jumper is placed in the wiring harness.