imx Parameter Identification (PI)
The game-changer for electronic motor testing. Comparison with conventional load-based methods shows that model-based Parameter Identification (PI) alone can test 1.500 to 10.000 e-Motors in depth in just one day.
imx Parameter Identification is a model-based method that identifies motor parameters based solely on measured current and voltage values (and angle of rotation for EC/BLDC motors).
The imx PI does not require a mechanical load unit (load machine/brake). The loads required for the test are generated by the rotor’s moment of inertia in conjunction with a specific dynamic test sequence.
It is not necessary to use special test systems for the imx PI. The method can also be used on conventional test benches. If required, passive motor tests (such as cogging torque, drag torque or generator voltage), active measurements (static/dynamic characteristics), endurance measurements and unloaded imx parameter identification can be performed on the same imx test stand.
The imx PI – a test type that provides comprehensive insight. It promises efficiency and versatility in e-motor testing and delivers what it promises.
You've got 15 seconds?
imx PI - is our most advanced method for determining the parameters of an electric motor. It differs significantly from conventional motor testing methods.
The advantages of imx PI are manifold, especially in the area of test times imx parameter identification beats all records.
While you are reading this short text here, the test of an electric motor would already be completed!
Versatile
Performant
Energy saving
Economical
imx Parameter Identification for BLDC / EC motors
The imx PI for permanently magnetized synchronous motors or EC motors is a highly dynamic test procedure. The load required for a motor test is generated by the moment of inertia of the rotor of the test specimen in combination with a specific, dynamic test sequence.
The excitation is motor-specific and is adapted to the test specimen. In practice, the sequence of a motor test can be divided into 4 different sections.
The ECPI measurement process is divided into 4 phases
- For motors with integrated angle encoders - quality and offset determination / teach-in of the angle offset for external sensors.
- Dynamic excitation - inductances, magnetic fluxes and inertia are determined.
- Run-out from the idle speed - to determine the friction. The excitations in part 2 and part 3 form the actual basis for imx parameter identification.
- Apply a constant DC current - to determine the winding resistances
Test motor parameters identified by imc PI
- The average phase resistance
- The excitation flux / generator constant
- The inductances - Ld & Lq; (saturation and cross-coupling captured by non-linear flux model)
- The sliding & static friction
- The mass inertia
Further results derived from this test
- The resistances of the individual phases
- The encoder offset
- The spectrum of the generator voltage
- For resolver / sin-cos encoders (offset, amplitude), the transformation ratio, phase shift and the spectrum
Automated processes
The imx PI is a fully automated process. It is quick to integrate and easy to execute.
Ready to use
The imx PI can be used with modern synchronous machines of any motor size.
Twice as economical
Compared to standard tests, the imx PI reduces both the initial cost and the cost per test.
imx Parameter Identification for DC motors
In the DC-PI method for brushed DC motors, each motor is also tested highly dynamically. As with the BLDC/EC motor, the load required for a test is generated by the moment of inertia of the rotor of the test specimen in combination with a motor-specific excitation process.
The excitation specified before the test is also matched to the device under test. Despite the high dynamics, the thermal loads remain relatively low due to moderate average motor currents. The motor rarely exceeds operating temperatures during testing.
An additional benefit of testing DC motors is that the speed and angle of rotation do not require the use of a sensor. This information is derived directly from the motor current signals. This eliminates the need for sensor adaptation or connection to a complex mechanical load line.
The DCPI measurement process is divided into 2 phases
- The run-out - to determine the friction
- The dynamic excitation - to determine further motor parameters
Test motor parameters identified by imc PI
- Resistance
- Excitation flux / motor constant
- Inductance
- Sliding & static friction
- The mass inertia
Further results derived from this test
- Idle speed and current
- Stall torque and current
- Electrical and mechanical time constant
- Speed and torque constant
Flexible tests
The simple mechanical test bench design enables the serial testing of different motors without having to modify it.
Simple setup
The design of an imx PI test stand is extremely simple and saves money in terms of investment and maintenance.
High test speed
The imx PI perfectly combines a high test depth for determining product quality with very short test times.
* The average test time for smaller DC motors using imx Parameter Identification is less than 15 seconds.
** The actual throughput of an end-of-line test depends on the motor size and the degree of automation of the test bench.
*** Depending on the motor size.
