Test system for testing an electric-motor-driven test object, and method for carrying out tests for measuring drive torques, rotational torques or load torques, or the heat generation of an electric-motor-driven test object
Patent Information
- Application Number
- PCT/AT2026/060056
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2025-02-27
- Filing Date
- 2026-02-26
- Publication Date
- 2026-09-03
Smart Images
Figure AT2026060056_03092026_PF_FP_ABST
Abstract
Description
[0001] PI33664WO / N February 26, 2026 AVL List GmbH
[0002] Test system for testing an electrically driven test object and methods for carrying out tests to measure drive, rotational or load torques or heat development of an electrically driven test object
[0003] The invention relates to a test system for testing an electrically driven test object with a flange to which an output shaft of the electrically driven test object can be connected and which is connected at its end opposite the output shaft to a shaft which is supported by an intermediate bearing and which is connected to a dynamometer which is electrically connected via an inverter to a control and evaluation unit with which the test object can be electrically connected and via which the test object can be controlled, as well as a method for carrying out tests to measure drive, rotational or load torques or heat developments of an electrically driven test object with such a test system.
[0004] With established electric motor test benches, various types of electric motors, for both hybrid and purely electric vehicle drives, can be tested and their durability verified. The electric motor can be connected to the test bench either as a standalone unit or together with the transmission or other drivetrain components. These test benches are used to analyze and determine electrical, mechanical, thermal, and acoustic properties. Functionality, reliability, and durability tests, as well as cold-start performance measurements, can be performed under realistic conditions. These systems can include an automation system that allows for fully automated test runs for all relevant test procedures. PI33664WO / N 26.02.2026 AVL List GmbH
[0005] These electric motor test systems feature a flange for coupling the test specimen or its output shaft, to which the other components for testing are connected. The other end of the flange is connected to a dynamometer controlled by an inverter. This dynamometer can either serve as an absorption unit, simulating a load for the test specimen, or the test specimen can be driven externally via the dynamometer as an electric load motor with adjustable and controllable parameters. The load motor is then driven at a controlled speed, and measurements of the rotational speed and applied torque are taken. For this purpose, dynamometers are used that incorporate an electric machine capable of operating as both a generator and an electric motor.
[0006] Furthermore, rotor locking tests have become known, in which a mechanical braking unit is installed for performance. This unit is usually actuated hydraulically, electrically, or pneumatically and has a brake disc by which the test specimen or its output shaft is held in place while a torque is applied. In these tests with a locked rotor, effects on reluctance torques, stray reactances, and short-circuit losses are usually investigated in a heated state.
[0007] Accordingly, these test systems can be used to determine all mechanical, electrical, and thermal properties of the test specimen, such as the torque characteristic, vibrations, noise, balance quality, DC operating voltage range, short-circuit current, rated and overload points, open-circuit voltage, and temperature profiles. PI33664WO / N 26.02.2026 AVL List GmbH
[0008] However, these well-known testing systems have the problem that increasingly higher torques and speeds of up to 50,000 rpm are required. -1 for the tests. While adapting the dynamometer and measuring units through appropriate upscaling presents only minor problems, the mechanical brake units must be removed from the test setup for such test systems. Otherwise, the high accelerations and centrifugal forces would cause the brake units to burst, posing a significant safety risk, especially for people in the vicinity.
[0009] The task therefore is to create a test system for testing an electrically driven test specimen, as well as a method for carrying out tests to measure drive, rotational or load torques or heat development of an electrically driven test specimen with such a test system, with which, on the one hand, test runs with speeds of over 20,000 min⁻¹ are possible. -1 can be carried out, and on the other hand, test runs with a blocked rotor can be carried out without having to change the setup of the test system.
[0010] This problem is solved by a test system for testing an electrically driven test object with the features of main claim 1 and a method for carrying out tests to measure drive, rotational or load torques or heat developments of an electrically driven test object with the features of claim 9.
[0011] The test system according to the invention has a flange that serves as a mechanical adapter between the test system and the test specimen. Accordingly, an output shaft of the electrically driven test specimen, which is an electric motor or drive train, is connected to the flange. PI33664WO / N 26.02.2026 AVL List GmbH
[0012] The test system can be designed for a vehicle. A shaft is attached to the opposite side of the flange and supported by an intermediate bearing, which forms an integral part of the test system. The shaft is connected to a dynamometer on the side of the test specimen opposite the intermediate bearing, or this shaft directly serves as the output shaft of the dynamometer. The dynamometer is powered by an inverter connected to a control and evaluation unit, which controls the dynamometer and transmits its measured values. The test system also includes a mechanical braking unit, typically consisting of an actuator and a braking element, such as a brake disc or brake shoe, which acts on the shaft.Accordingly, a first braking force can be mechanically applied to the shaft via the mechanical braking unit to slow down or completely block the rotor of the test specimen. In addition to this first braking force, a second braking force can be applied to the shaft according to the invention by controlling the dynamometer via the inverter using the control and evaluation unit in such a way that the dynamometer actively acts as an electric brake. The braking unit can be arranged between the intermediate bearing and the dynamometer or between the intermediate bearing and the flange. This system makes it possible to design the mechanically acting braking unit to be so small and lightweight that it can withstand speeds of up to 50,000 rpm. -1withstands without bursting, as the lower masses significantly reduce the centrifugal forces acting on the mechanical braking unit. Nevertheless, using the dynamometer as an electric brake provides a sufficiently large holding force to completely block the test specimen's rotor even at very high torques of up to 1000 m. Accordingly, no modifications to the test system are necessary to perform the various measurements. A mechanical PI33664WO / N 26.02.2026 AVL List GmbH
[0013] Aside from the time loss, any modification always results in a change in the temperature of the electric motor. With the test system according to the invention, tests and / or measurements with a blocked rotor can be carried out immediately after targeted and constant temperature conditioning in order to obtain high-quality results. The test system can also include a gearbox and / or two shaft outputs.
[0014] In the inventive method for conducting tests to measure drive, rotational, or load torques, or the effects of heat generation in an electrically driven test specimen, the control and evaluation unit first engages the mechanical brake unit to lock the shaft in a first test, and then the test specimen is subjected to a drive torque. Simultaneously, the dynamometer is also subjected to a torque acting in the opposite direction to the torque of the test specimen. Subsequently, at least one of the measured variables—current, voltage, power consumption, rotational speed, torque, generated heat, and temperature of the test specimen and / or the dynamometer—can be measured. At the end of the test run, the torques of the test specimen and the dynamometer are reset to zero, and the mechanical brake unit is released.By applying the opposing torque to the dynamometer, a smaller mechanical braking unit can be used, as the dynamometer acts as an electric brake, thus amplifying the braking force without otherwise affecting the test specimen. Accordingly, the mechanical braking unit can also be used for test runs requiring high speeds or speed gradients, since it has significantly lower inertia and therefore experiences a smaller acceleration force. The tests are usually conducted using a climate chamber to ensure appropriate temperature conditioning of the test specimen. (A modification of the PI33664WO / N 26.02.2026 AVL List GmbH.)
[0015] The testing system between the different tests can therefore be omitted, so that various measurements can be carried out fully automatically in a short time and / or under constant test specimen temperatures on an identically constructed testing system.
[0016] Preferably, the dynamometer is designed as an electric motor / generator, which can generate a load torque and a drive torque. This design allows the counter-torque to be applied by simply controlling the dynamometer, or enables controlled driving of the test specimen via the dynamometer.
[0017] In a preferred embodiment, the test specimen can be controlled by the control and evaluation unit such that a first torque can be generated, and the dynamometer can be controlled via the inverter by the control and evaluation unit such that a torque in the opposite direction to the torque of the test specimen can be generated, which acts as a second, electrical braking force. These control operations can thus be carried out fully automatically via the control and evaluation unit, ensuring complete synchronization. Particularly preferably, the torque acting as the second, electrical braking force is between 10% and 90% of the torque of the test specimen.
[0018] For testing modern electrically driven test specimens, the test specimen and / or the dynamometer can be controlled by the control and evaluation unit in such a way that the test specimen is rotated at a speed of over 20,000 rpm. -1is driven. Especially these high speeds, sometimes exceeding 50,000 rpm. -1 are required today because high heat flows and shaft loads occur precisely at these speeds. PI33664WO / N 26.02.2026 AVL List GmbH
[0019] The mechanical brake unit is advantageously actuated hydraulically, pneumatically, or electrically to apply the initial braking force. Particularly when using hydraulic and pneumatic brakes, high braking forces can be applied very quickly even with relatively small brakes, while the control system is simplified for electrically operated brakes.
[0020] The mechanical brake unit is preferably also electrically connected to the control and evaluation unit, so that the entire control of the test system can be carried out via one unit, allowing the control variables and times to be precisely coordinated.
[0021] The flange advantageously serves as a measuring flange for torque measurement, so that no additional components need to be used and the setup of the test system is simplified.
[0022] In a preferred embodiment, the intermediate bearing, a mounting unit for securing the test specimen, the mechanical brake unit, and the dynamometer are fixed to a frame, allowing the various parts to be precisely aligned with one another. Furthermore, the various components can be permanently installed, as no modifications are required, thus improving durability despite the high forces involved.
[0023] In a further development of the method, the torque generated by the dynamometer, which opposes the torque of the test specimen, is smaller in magnitude than the torque of the test specimen. Accordingly, energy can be saved, since the remaining holding force can be provided by the mechanical braking unit. PI33664WO / N 26.02.2026 AVL List GmbH
[0024] It is particularly advantageous if the torque generated by the dynamometer is 70% to 90% of the torque of the test specimen. This results in a relatively strong electrical braking effect and significantly reduces the load on the mechanical braking unit, allowing it to be designed to be particularly small.
[0025] Furthermore, preferably, the control and evaluation unit uses either a setpoint that corresponds to the value of the target torque sent to the test specimen (or with a factor of 30% to 90% of the torque of the test specimen), or a setpoint that corresponds to the value of the measured torque, or a calculated setpoint that is formed from components of the value of the measured torque and the target torque sent to the test specimen, or a controlled variable whose input can be formed from the actual value of the measured and / or calculated torque and / or from the target torque sent to the test specimen.
[0026] In a further development of the procedure, in a second test the mechanical brake unit is opened so that no braking force is exerted and the test specimen is subjected to a drive torque by the control and evaluation unit and driven to speeds exceeding 20,000 rpm. -1The device is accelerated, while the dynamometer simultaneously operates as a generator, creating a load for the test specimen. At least one of the following parameters is measured: current, voltage, power consumption, rotational speed, torque, heat generated, and temperature of the test specimen and / or the dynamometer. Accordingly, the brake disc of the mechanical brake unit rotates during the test specimen; however, the small size of the brake prevents damage to the brake disc even during these tests.
[0027] In the following, by generating a torque on the dynamometer in the opposite direction to the torque of the test specimen, PI33664WO / N 26.02.2026 AVL List GmbH
[0028] By generating a braking force using the mechanical brake unit, the shaft, and thus the output shaft, is blocked, and at least one of the measured variables—current, voltage, power consumption, speed, torque, generated heat, and temperature of the test specimen and / or the dynamometer—is recorded. Such abrupt braking allows tests to be performed immediately after the test specimen reaches a specific temperature. Additionally, the time loss between different measurements is minimized, enabling more test runs to be performed in a shorter time.
[0029] In a third test, the mechanical brake unit is also open, so no braking force is applied. The control and evaluation unit regulates the dynamometer's speed to defined speeds, thus using it as a drive motor for the test specimen. At least one of the following parameters is measured: current, voltage, power consumption, speed, torque, heat generated, and temperature of the test specimen and / or the dynamometer. Such a test can be used, for example, to determine the cogging torque of the test specimen and to make statements about its behavior during deceleration.
[0030] This creates a test system for testing an electrically driven test specimen, as well as a method for conducting tests to measure drive, rotational, or load torques or heat generation of an electrically driven test specimen. This enables various high-stress test runs to be performed quickly and / or with high quality. Damage to the test system is reliably prevented. No modifications of any kind are necessary. In addition, central control and evaluation of the test runs are possible, allowing for the time-optimized control of the various components. PI33664WO / N 26.02.2026 AVL List GmbH
[0031] An embodiment of a test system according to the invention for testing an electrically driven test object is shown in the figure and is described below, as is the associated method for carrying out tests to measure drive, rotational or load torques or heat developments of an electrically driven test object.
[0032] The figure shows a schematic representation of a testing system according to the invention in side view.
[0033] The test system consists of a frame 10 on which a dynamometer 12 in the form of an electric motor / generator dynamometer is mounted. Its shaft 14 is rotatably mounted via an intermediate bearing 16, which is also attached to the frame 10. The end of the shaft 14 is attached to a flange 18, which is designed as a torque flange and can therefore measure torques acting on the flange 18.
[0034] Additionally, a mounting unit 20 for attaching an electrically driven test specimen 22 is provided on the frame 10. This test specimen can be, in particular, a drive motor of an electric vehicle or a drive motor with a downstream gearbox or other downstream components of the drive train. The mounting unit 20 has a through-hole for an output shaft 24 of the test specimen, the end of which is attached to the torque flange 18 on the side opposite the dynamometer 12. Accordingly, a connection for transmitting torques between the test specimen 22 and the dynamometer 12 is established via the output shaft 24, the torque flange 18, and the shaft 14. PI33664WO / N 26.02.2026 AVL List GmbH
[0035] The dynamometer 12 is connected to an inverter 26, which supplies the dynamometer 12 with a regulated voltage. The inverter 26 is controlled by a control and evaluation unit 28, which is electrically connected to the inverter 26. This unit also centrally controls the device under test 22 and is additionally connected to all measuring units, such as the torque flange 18, temperature sensors 30, current and voltage sensors 32, and vibration meters 34, allowing their measured values to be evaluated directly.
[0036] The test system also includes a climate chamber 36 connected to a conditioning unit 38, enabling test runs to be performed under various thermal conditions. Efficiency tests, characteristic curve recordings, and endurance tests can be carried out using this test system in a known manner. Additionally, noise analyses can be performed by exciting the test specimen and analyzing all noise-generating forces using a noise transducer. This serves to assess the quality of rolling bearings or the effect of electrical forces.
[0037] The climate chamber 36 can consist of two parts and can also enclose only the test specimen 22. In this version, the front panel of the climate chamber 36 is permanently connected to the receiving unit 20, while the rear part of the climate chamber 36 rests on the ground or is mounted on the frame 10.
[0038] Measurements are performed in which the dynamometer 12 serves as a generator and thus as a load for the test specimen 22. The rotation of the test specimen 22 induces a measurable voltage in the coils of the dynamometer 12, which is acting as a generator. The rotational speed and power of the test specimen 22 can be calculated from this voltage. (PI33664WO / N 26.02.2026 AVL List GmbH)
[0039] that different test cycles can be run with varying speeds and engine loads. For this purpose, the test specimen 22 is subjected to speeds of up to and exceeding 50,000 rpm. -1 The speed of the dynamometer 12 is controlled by the control and evaluation unit 28, and measurement data is recorded throughout the entire test cycle. A load can be simulated by appropriately controlling the dynamometer 12, with its holding torque being regulated via the control and evaluation unit 28.
[0040] Additionally, the dynamometer 12 can also be used as a drive motor, which drives the test specimen 22. This allows cogging torques and additional information on the thermal load of the test specimen 22 to be obtained, which in this case is operated in overrun mode, i.e., without current. During these measurements, the dynamometer 12 is driven at a speed controlled by the inverter 26 via the control and evaluation unit 28.
[0041] According to the invention, the test system additionally features a mechanical brake unit 40 that is rigidly connected to the frame 10. The brake unit 40 could also be installed directly on the intermediate bearing 16. This brake unit 40 has a hydraulic or pneumatic brake actuator 42, which could also be electromechanical and is electrically connected to the control and evaluation unit 28. The brake actuator 42 acts on a brake element 44 attached to the shaft 14, thereby exerting a braking force on the shaft 14 and thus also on the test specimen 22. A brake disc, for example, can be used as the brake element 44. Additional tests are performed with this brake unit 40 in which the shaft 14, and thus the output shaft 24 and the rotating parts of the test specimen 22 located behind it in the drive train, are to be held in place in order to perform tests on the blocked rotor. PI33664WO / N 26.02.2026 AVL List GmbH
[0042] During these tests, a target angle is specified to the inverter 26 via the control unit 28 to adjust the rotor to any angle between 0 and 360°. Alternatively, the control unit 28 can also control this rotor angle itself. After the system consisting of the control unit 28, inverter 26, and dynamometer 12 has adjusted to the target angle, the control and evaluation unit 28 sends a command to the actuator 42, which then activates the brake unit 40 and blocks the shaft 14 and the output shaft 24, thus also blocking the rotor of the test specimen 22. The control and evaluation unit 28 can then specify any desired torque to the test specimen 22, thereby applying a defined torque to the output shaft 24 of the test specimen 22. The applied torque can be measured at the torque flange 18.By blocking the rotor or shaft 14, and thus the output shaft 24, a high heat flow develops in the test specimen 22. This allows conclusions to be drawn about the thermal load capacity of the test specimen 22 and its temperature profiles. For PMSM (Permanent Magnet Synchronous Machines), the test run with a blocked rotor is primarily used to determine the effect on the output torque or the effect of the reluctance torque at different rotor angles and electric motor temperatures. For asynchronous machines, this test is mainly used for short-circuit measurements to determine stray reactances and short-circuit losses. Additionally, the effect of stray reactances at different electric motor temperatures can also be investigated in asynchronous machines. The test with a blocked rotor can also be used to validate the control of the test specimen at various rotor angles under load at zero speed.The tests with a blocked rotor can of course also be applied to other motor types to investigate their specific effects. PI33664WO / N 26.02.2026 AVL List GmbH.
[0043] However, when high torques of several hundred Nm are required, the mechanical brake unit must generate such a large holding force that this would only be possible with correspondingly large brake actuators 42 and, above all, brake elements 44. Since these, however, operate at speeds exceeding 20,000 rpm -1Since the brakes tended to burst, in known systems the brakes had to be removed or taken off the shaft 14 during the other tests described. To prevent this, smaller mechanical brake units 40 with lower holding forces are installed according to the invention. These units can withstand the load at high speeds but cannot provide the full required braking force. The missing holding force is generated electrically via the dynamometer 12 by applying a torque to it that opposes the torque of the test specimen 22 and is, for example, only 80% of its torque. The required target torque or control variable for the dynamometer 12 or the inverter 26 is generated by the control and evaluation unit 28. The target torque is either the measured torque from the measuring flange 18 and immediately output as the target value to the dynamometer 12, or the identical or...A percentage of the target torque, which is also sent to the test specimen 22, is sent to the dynamometer 12.
[0044] The target torque is either the measured torque of measuring flange 18 or the target torque that is also sent to the test specimen 22.
[0045] The target torque is preferably applied precisely simultaneously to the test specimen 22 and the dynamometer 12, so that the brake actuator ideally only needs to contribute a small amount of braking torque. To achieve optimal brake force distribution between the mechanical brake actuator 42 and the dynamometer 12, the target torque to the dynamometer 12 can be limited as a percentage of the test specimen target value in a range of 70% to 90%. Experience has shown that percentage values in the range of 70% to PI33664WO / N 26.02.2026 AVL List GmbH
[0046] 80% particularly proven. The dynamometer 12 is accordingly torque-controlled by the control and evaluation unit 28 during this test run.
[0047] The test run begins with the test specimen 22 being at rest. The mechanical brake unit 40 is then closed via the control and evaluation unit 28. Subsequently, the control and evaluation unit is actuated to generate a desired torque on the test specimen 22 and an opposing torque of the same or lesser magnitude on the dynamometer 12. The holding force applied by the electric brake (dynamometer 12) and the mechanical brake unit 40 should exceed the rotational force generated by the torque on the test specimen 22, thus locking the output shaft 24 and the shaft 14. The desired measurements can then be performed with the rotor locked, in particular the torque measurements at defined rotor angles and the thermal load measurement.
[0048] Immediately following or immediately before this, the other load and freewheel test runs can also be carried out, in which, as described above, the dynamometer is used either as a drive motor or as an absorber unit. In both cases, the test specimen 22, and thus also the output shaft 24 and the shaft 14, can be rotated at speeds of 20,000 to 50,000 rpm with the mechanical brake unit 40 open, i.e., the brake actuator 42 not actuated. -1 or more are driven to measure the current, voltage, power consumption, speed, torque, heat generated, temperature or load.
[0049] The mechanical brake unit 40 can also be used together with the electric brake in the form of the appropriately controlled PI33664WO / N 26.02.2026 AVL List GmbH
[0050] The dynamometer 12 can be used to stop a high-speed rotating rotor of the test specimen 22 in the shortest possible time by closing the mechanical brake unit 40 and simultaneously switching the dynamometer to torque control via the control and evaluation unit 28, generating a braking torque at the dynamometer 12. This allows tests on the test specimen 22 to be carried out immediately after it reaches a specific temperature or load. This eliminates run-down times and enables tests to bring the test specimen 22 to an immediate standstill. The test specimen can either continue to be subjected to torque or be de-energized if only braking is required to perform subsequent tests.Should the braking force of the mechanical brake unit 40 be too great when locking up from very high speeds, it is also conceivable to initially brake only with the electric brake, i.e. the dynamometer 12, and to switch on the mechanical brake unit 40 at a lower speed.
[0051] If the test specimen continues to be powered and both brakes are applied, a state of the test specimen 22 is simulated in which a driver of an electric vehicle simultaneously presses the accelerator pedal and brakes completely, resulting in high forces acting on the drive train, which can thus also be tested with regard to its durability.
[0052] No modifications to the test system are necessary when testing a test specimen. Instead, various test runs can be performed in a very short time, both with a blocked rotor and under load or in thrust mode.
[0053] It should be clear that the described embodiment is not to be interpreted restrictively, but rather that various modifications are conceivable. In particular, the measurements to be taken can be PI33664WO / N 26.02.2026 AVL List GmbH
[0054] Various measuring devices are required. Furthermore, not all described tests necessarily need to be performed on the described test system. In particular, legal requirements and manufacturer specifications may necessitate additional, undocumented test runs, or eliminate the need for described ones. Naturally, the test runs can also be performed in any order.
Claims
PI33664WO / N February 26, 2026 AVL List GmbH PATENT CLAIMS 1. Test system for testing an electrically driven test object (22) with a flange (18) to which an output shaft (24) of the electrically driven test object (22) can be connected and which is connected at its end opposite the output shaft (24) to a shaft (14) which is supported by an intermediate bearing (16) and which is connected to a dynamometer (12) which is electrically connected via an inverter (26) to a control and evaluation unit (28) to which the test object (22) can be electrically connected and via which the test object (22) can be controlled. characterized by the fact that The test system further comprises a mechanical brake unit (40) via which a first mechanical braking force can be applied to the shaft (14) and the dynamometer (12) can be controlled via the inverter (26) by means of the control and evaluation unit (28) in such a way that a second electrical braking force can be actively applied to the shaft (14).
2. Test system for testing an electrically driven test object (22) according to claim 1, characterized by the fact that the dynamometer (12) is designed as an electric motor / generator, via which a load and a drive torque can be generated.
3. Test system for testing an electrically driven test object (22) according to claim 1 or 2, characterized by the fact that the test specimen (22) can be controlled by the control and evaluation unit (28) in such a way that a first torque can be generated and the PI33664WO / N 26.02.2026 AVL List GmbH The dynamometer (12) can be controlled via the inverter (26) by means of the control and evaluation unit (28) in such a way that a torque in the opposite direction to the torque of the test specimen (22) can be generated, which acts as a second braking force.
4. Test system for testing an electrically driven test object (22) according to one of the preceding claims, characterized by the fact that the test specimen (22) and / or the dynamometer (12) can be controlled by the control and evaluation unit (28) in such a way that the test specimen (22) is rotated at a speed of over 20,000 min -1 is powered.
5. Test system for testing an electrically driven test object (22) according to one of the preceding claims, characterized by the fact that the mechanical brake unit (40) for applying the first braking force can be actuated hydraulically, pneumatically or electrically.
6. Test system for testing an electrically driven test specimen (22) according to one of the preceding claims, characterized by the fact that the mechanical brake unit (40) is electrically connected to the control and evaluation unit (28).
7. Test system for testing an electrically driven test specimen (22) according to one of the preceding claims, characterized by the fact that The flange (18) is designed as a measuring flange for torque measurement. PI33664WO / N 26.02.2026 AVL List GmbH 8. Test system for testing an electrically driven test object (22) according to one of the preceding claims, characterized by the fact that the intermediate storage unit (16), a receiving unit (20) for securing the test specimen (22), the mechanical brake unit (40) and the dynamometer (12) are fixed firmly on a frame (10).
9. Method for carrying out tests to measure drive, rotational or load torques or heat developments of an electrically driven test specimen (22) using a test system according to one of the preceding claims, characterized by the fact that In a first test, the control and evaluation unit (28) closes the mechanical brake unit (40) to block the shaft (14) and then the test specimen (22) is subjected to a drive torque, while at the same time the dynamometer (12) is subjected to an opposing torque via the control and evaluation unit (28) and then at least one of the measured variables current, voltage, power consumption, speed, torque, generated heat and temperature of the test specimen (22) and / or the dynamometer (12) is measured and finally the torques of the test specimen (22) and the dynamometer (12) are set to zero and the mechanical brake unit (40) is released.
10. Method for carrying out tests to measure drive, rotational or load torques or heat development of an electrically driven test specimen (22) according to claim 9, characterized in that PI33664WO / N 26.02.2026 AVL List GmbH the torque generated by the dynamometer (12) which is opposite in magnitude to the torque of the test specimen (22) is smaller is the torque of the test specimen (22).
11. Method for carrying out tests to measure drive, rotational or load torques or heat developments of an electrically driven test specimen (22) according to claim 9 or 10, characterized by the fact that the torque generated by the dynamometer (12) is 70% to 90% of the torque of the test specimen (22).
12. Method for carrying out tests to measure drive, rotational or load torques or heat developments of an electrically driven test specimen (22) according to one of claims 9 to 11, characterized by the fact that In a second test, the mechanical brake unit (40) is opened so that no braking force is exerted and the test specimen (22) is subjected to a drive torque by the control and evaluation unit (28) and is driven to speeds above 20,000 min. -1 is accelerated, while at the same time the dynamometer (12) is operated as a generator, which forms a load for the test specimen (22) and at least one of the measured quantities current, voltage, power consumption, rotational speed, torque, generated heat and temperature of the test specimen (22) and / or the dynamometer (12) is measured.
13. Method for carrying out tests to measure drive, rotational or load torques or heat development of an electrically driven test specimen (22) according to claim 12, PI33664WO / N 26.02.2026 AVL List GmbH characterized by the fact that In the following, by generating a torque on the dynamometer (12) in the opposite direction to the torque of the test specimen (22) and generating a braking force by means of the mechanical brake unit (40), the shaft (14) and thus the output shaft (24) is blocked, and at least one of the measured quantities current, voltage, power consumption, speed, torque, generated heat and temperature of the test specimen (22) and / or the dynamometer (12) is measured.
14. Method for carrying out tests to measure drive, rotational or load torques or heat developments of an electrically driven test specimen (22) according to one of claims 9 to 13, characterized by the fact that In a third test, the mechanical brake unit (40) is opened so that no braking force is exerted and the dynamometer (12) is controlled by the control and evaluation unit (28) to defined speeds and serves as a drive machine for the test specimen (22), and at least one of the measured variables current, voltage, power consumption, speed, torque, generated heat and temperature of the test specimen (22) and / or the dynamometer (12) is measured.