Electric Vehicle Motor & Controller Test


This application note provides an example of testing an E-Motor and Controller for electric vehicles. Traditional test setups require a dedicated DC source and load in parallel to deal with bi-directional energy flow. This can require a complex test setup to coordinate energy flow and to avoid damaging expensive equipment.
The PSB 9000 is a bi-directional DC source and electronic load which simplifies the test setup, avoids catastrophic damage and decreases test times. This electronic load has the unique option of back-feeding converted energy into the grid.


With the UK Government stating that the majority of new cars and vans will be electric by 2030, it is important that the UK Automotive Industry continues to research and develop new battery and motor technologies. There is a greater desire for reliability and longevity which will reduce the need for automotive recalls.
Electric Motor and Drive-Train (Electric Mobility) Testing is a critical part of bringing any electric drive-train into production. In this note the requirements for an electric Drive-Train test cell are discussed. The implementations of such test cells are described, and examples of test results are provided. The energy and power requirements for three-phase motor and controller, Unit Under Test (UUT) connected through a common DC bus are also described.
The data used represents various steady state load conditions during durability test cycles. This “Smart Green Technology” concept not only reduces the energy requirement from the grid but also eliminates the inefficiencies by putting energy back on the grid.

Test Method

The E-Motor rates at 6,000 RPM in clockwise direction, pulling positive current up to 10 Adc (Source).

After approximately 100msec, the control controller turns voltage to the motor OFF and the current quickly dissipates into the PSB 9000 at approximately -5 Adc (Sink).
Voltage is re-applied and the motor spins back up to steady state current of 10 Adc.


Energy Recovery

Test Condition

UUT: Controller maximum power: 750 Vdc / 800 Adc (the test below provides 320 Vdc and programmed to 10 Adc.
The motor RPM is approximately 6,000 RPM, Clockwise and Counter-Clockwise at no-load condition.