Electric Motor and Inverter TestingPower and efficiency testing of electric motor and inverter

Electric motor and inverter testing

As electric motors face increasing energy efficiency requirements, adherence to standards like the IEC 60034 is crucial. This standard mandates that all asynchronous motors meet at least the IE2 efficiency level. Unlike before, when losses were estimated at 0.5%, precise determination of these losses is now necessary. Achieving accurate efficiency and loss measurements demands the highest precision across the entire measurement chain.

The Dewesoft electrical power analysis solutions, combined with additional current sensor calibration options, ensure the highest accuracy for all power measurements. Our modular hardware design allows for the measurement of up to 12-phase motors, as well as mechanical parameters like speed, torque, and deformation.

Our power analyzers can also measure parameters such as vibration, sound level, and temperature, all fully synchronized with the power parameters. The inclusion of power quality analysis (fundamental power, harmonics, THD, etc.) further enhances its comprehensive analysis capabilities.

Combined electric motor and inverter testing

Combined motor and inverter testing demands a high number of input channels for voltage and current measurements along with fully synchronized data acquisition. The Dewesoft solution enables the measurement of 8x 3-phase systems using a single device, allowing for synchronous measurement of an entire power system (e.g., electric vehicle, aircraft, ship). This feature integrates all functionalities of motor and inverter testing and supports additional parameters such as speed, torque, temperature, video, GPS & IMU, and CAN/CAN FD.

Traditionally, testbed applications required multiple devices, including a power analyzer, oscilloscope, data logger, and CAN logger. The Dewesoft solution consolidates all these capabilities into a single device, storing raw data at the full sampling rate and enabling real-time analysis.

The DewesoftX DAQ software offers unique post-processing functionalities, allowing for analysis (mathematics, power analysis) after measurement completion. You can even change settings or correct measurement mistakes, such as adjusting phase voltages if they were connected incorrectly, without repeating the measurement. This innovative workflow provides exceptional freedom and flexibility.

Optimize your motor performance

• Maximize Performance and Longevity: By understanding the motor’s efficiency map, operators can run the motor in its optimal range, ensuring peak performance and extending its lifespan.

• Improve Energy Consumption for All Machines: Identifying areas of maximum efficiency helps run the motor under conditions that minimize energy consumption, benefiting both large and small machines.

• Predict Potential Failures: Analyzing parameters like torque ripple can indicate potential mechanical issues or wear, enabling timely maintenance to prevent breakdowns.

• Ensure Safety and Prevent Hazards: Early detection of anomalies, such as unusual torque ripple, can avert hazardous operating conditions.

• Enhance Control Algorithms: Understanding the motor’s characteristics allows for the fine-tuning of control algorithms, resulting in smoother operation and better responsiveness.

• Benchmarking: Companies can compare performance across different motor brands or designs to choose the best fit for their applications.

Typical power analyzer configuration

For a typical configuration, we recommend using our high-channel SIRIUS® R4 and SIRIUS® R8 data acquisition systems or a completely modular and distributed SIRIUS® XHS solution with network and PTP synchronization:

• 4 - 12x high voltage inputs

• 4 -12x current inputs

• 1x torque input

• 1x speed input

• Additional inputs - analog (IEPE, thermocouple), digital, CAN/CAN FD, GPS & IMU, video, etc.

If you would like more information, you can visit our Power Analyzers product page to see all available power analyzers and choose the most appropriate one for your testing scenario.

Frequency source selection

The Dewesoft Power Analyzer allows users to choose the frequency source for their measurements. The available options are:

• Voltage

• Current

• External frequency source

This feature is especially beneficial when measuring inverters. Inverter measurements can be tricky due to the PWM-modulated voltage signal, which makes it difficult to determine the correct period of time. On the other hand, the current signal is generally less distorted because of the high inductance in the motor coil.

Therefore, using the current signal as the frequency source is often a better choice for inverter measurements. This approach ensures accurate frequency determination for every application.

Real-time power output measurement

Mechanical power

Measure the real-time power output of the motor using mechanical sensors at the shaft. This enables users to assess the motor’s performance under various conditions, ensuring it operates at optimal levels.

By providing precise data on the motor’s mechanical power, users can make informed decisions to enhance efficiency, detect potential issues early, and maintain peak performance. This comprehensive understanding of the motor’s output helps in fine-tuning operations and maximizing the motor’s lifespan.

Mechanical rotation

An integrated counter math module monitors the motor’s performance across various operating conditions. This helps identify regions of maximum efficiency and enables operators to run motors at optimal points, ensuring peak performance and energy savings. The counter module can work with any counter and encoder sensor, ensuring seamless compatibility and flexibility regardless of the specific counter equipment used.

Torque ripple analysis: ensuring smooth motor operation

Torque ripple is a crucial metric that captures variations in the motor’s torque during rotation. By analyzing torque ripple, Dewesoft power analyzers provide valuable insights into potential mechanical issues, imbalances, or inefficiencies that could impact the motor’s smooth operation and longevity.

This detailed analysis helps identify problems early, allowing for timely maintenance and ensuring optimal performance and extended life of the motor. With Dewesoft power analyzers, you can ensure your electric motor and inverter systems are running efficiently and reliably.

Energy calculation

The Dewesoft Power module also automatically calculates the energy of the measured system. This feature enables the calculation of both positive and negative energy, providing a comprehensive understanding of the system's performance.

Additionally, the Math module allows users to calculate efficiency, essential for evaluating and optimizing system operations. This capability is particularly beneficial in various applications, such as:

• Recuperation Brake Systems: Analyze the energy recovered during braking to improve system efficiency and performance.

• Battery Testing: Measure energy input and output to assess battery efficiency, capacity, and overall health.

These features make Dewesoft Power Analyzers a versatile and powerful tool for energy calculation and efficiency analysis across different applications.

e-NVH: Lead the Assessment and Optimization of your Electric Unit

Enhance your electric power testing with parallel NVH/e-NVH analysis of electric motors, transmissions, and drivetrains using a single instrument and the easy-to-use DewesoftX software. Identify and resolve vibration, noise, and harshness issues to meet both customer and industry standards.

Collaborate seamlessly with development and simulation teams to correlate real-world and simulated data. Improve overall system performance, identify root causes, and solve NVH challenges with DewesoftX’s comprehensive toolkit:

Rotating Machinery Analysis

• SuperCounter Technology: High-precision rotation detection.

• Run-Up & Coast-Down: Analyze machine behavior during speed changes.

• Order Extraction & Tracking Filters: Isolate and follow specific harmonics in real time.

• Waterfall & Campbell Diagrams: Visualize frequency vs. RPM for resonance detection.

• Time Synchronous Averaging (TSA): Suppress noise in rotating measurements.

• Shaft Centerline Analysis: Monitor shaft position and orbits.

Advanced FFT & Frequency Analysis

• High-Resolution FFT: Focus on specific frequency bands.

• Spectral Metrics: RMS, Peak, Peak-to-Peak, PSD, max-hold, and moving average.

• Octave (CPB) Analysis: Ideal for noise and sound measurement.

• 2D/3D Plotting Tools: Quickly highlight target frequencies and markers.

• Modal & ODS Analysis: Visualize deflection shapes in operational conditions.

Modal Testing/Modal Analysis

• Impact Hammer & Shaker Testing

• Identify natural frequencies, damping, and mode shapes.

• Animate deflection shapes for structural vibration insights.

Real-Time Monitoring & Alarms

• Threshold Alarms: Vibration, Orders, RPM.

• Condition Monitoring: Track machine health continuously.

• Sound Analysis: Sound quality, power, intensity, and octave bands.

Learn out about all our NVH testing solutions.