Partial Discharge-Free Power Supply for Transformer Testing
SDACME manufactures variable-frequency AC test power supplies for transformer partial-discharge and induced-voltage testing, providing controlled voltage, frequency and transformer-isolated sine-wave output for demanding transformer test applications.

Variable-Frequency Test Power for Transformer Applications
SDACME partial discharge-free power supplies are designed as AC test power sources for transformer testing where adjustable voltage, frequency, waveform quality and controlled test conditions are required.

Test Power Source — Not the PD Measuring Instrument
The frequency converter supplies controlled AC excitation to the transformer test circuit. Partial-discharge detection and measurement are performed by the corresponding measurement equipment used in the complete test arrangement.
Adjustable AC voltage and frequency for applicable transformer test requirements.
Measurement, sensing and other test-system components are configured according to the required test arrangement.
- Partial Discharge Testing
- Induced Withstand Voltage Testing
- No-Load Loss Testing
- Load Testing
- Temperature-Rise Testing
Series Scope and Reference Electrical Specifications
The SDACME partial discharge-free power supply series covers a wide capacity range for transformer test power applications. Final electrical configuration is reviewed against the required transformer and test conditions.
Available capacity range stated for the partial discharge-free frequency converter series.
Designed as the controllable power source for applicable transformer testing requirements.
Also applicable to selected no-load, load and temperature-rise test power requirements.
Electrical Performance for Project Evaluation
The values below represent the reference electrical configuration used for project evaluation. Final interfaces are confirmed against the selected equipment configuration.
| Input Phase | Three-phase, three-wire + ground |
|---|---|
| Reference Input Voltage | 480 V ±10% |
| Reference Input Frequency | 60 Hz ±5 Hz |
| Input Power Factor | >0.92 |
| Output Phase | Three-phase, four-wire + ground |
| Output Isolation | Transformer isolated |
| Reference Output Voltage | 0–1000 V L-L |
| Voltage Stability | ≤±1% |
| Reference Output Frequency | 45.0–200.0 Hz |
| Frequency Adjustment | 0.1 Hz |
| Frequency Stability | ≤±0.01% |
| Source-Voltage Effect | ≤±1% |
| Load Effect | ≤±1% |
| Output Waveform | Sine wave |
| Waveform Distortion | ≤3% under resistive load |
| Three-Phase Angle | 120° ±1° |
| Efficiency | ≥88% |
Input conditions, required output voltage, test frequency, capacity and phase arrangement should be reviewed together with the transformer test requirement before the final equipment configuration is defined.
Test Power for Partial Discharge and Induced-Voltage Applications
SDACME partial discharge-free power supplies provide controlled variable-frequency AC power for transformer test arrangements where stable excitation, adjustable frequency and electrical isolation are required.
Primary Application Partial Discharge Testing
The power supply provides adjustable AC excitation for transformer partial-discharge test arrangements, serving as the controlled test power source used together with the required measurement equipment.
- Variable-frequency AC excitation
- Transformer-isolated output
- Controlled voltage and frequency
- Designed for transformer test power applications
Primary Application Induced Withstand Voltage Testing
Adjustable-frequency output supports transformer induced-voltage and induced-withstand test requirements where the excitation frequency and test voltage must be matched to the selected test arrangement.
- Adjustable test frequency
- Controlled AC test voltage
- Sine-wave output
- Project configuration based on test requirements
Additional Transformer Test Applications
The same power source can also support selected transformer test duties when the required electrical conditions match the configured power-supply capability.
Provides AC test power for applicable transformer no-load test arrangements.
Can provide the required test power source for selected transformer load test configurations.
Supports applicable transformer temperature-rise test power requirements according to the selected configuration.
Test measurement, sensing, transformer connections and other test-system components are selected according to the required test method and project configuration.
Controlled AC Power for Sensitive Transformer Test Conditions
Transformer partial-discharge and induced-voltage testing place particular requirements on the excitation power source. Output waveform, voltage stability, frequency stability, electrical isolation and output conditioning all contribute to a controlled transformer test environment.
The purpose of the test power source is not simply to change frequency. It must provide a controlled AC output suitable for the selected transformer test arrangement.
Sine-wave output supports transformer test excitation where waveform quality is an important part of the test power requirement.
Transformer-isolated output separates the configured test output from the incoming supply as part of the test power architecture.
The power conversion and output conditioning stages are designed to provide controlled AC power for applicable transformer test requirements.
Controlled voltage and frequency help maintain the required excitation conditions throughout the selected test procedure.

Key Output Characteristics
The power supply provides the excitation source. Final measurement performance also depends on the transformer under test, measurement equipment, test connections, grounding and the overall test setup.
Controlled Power Conversion from Grid Input to Transformer Test Output
The partial discharge-free power supply converts the incoming AC supply into a controlled, electrically isolated and conditioned variable-frequency AC output for the selected transformer test requirement.
Power Conversion Architecture
The public architecture below shows the functional power path used to explain system capability without exposing internal control, circuit or component-level implementation details.
Output voltage and frequency can be matched to the applicable transformer test requirement within the selected configuration.
Electrical isolation forms part of the power path between the incoming supply and the transformer test output.
The final output stage provides controlled sine-wave test power for applicable transformer testing.
The final power path, electrical interfaces and equipment configuration are selected according to the transformer rating, available input supply, required output conditions and intended test application.
Configure the Power Source Around the Transformer Test Requirement
The appropriate partial discharge-free power supply is selected from the actual transformer test duty, required electrical conditions and available facility supply. Capacity alone is not sufficient to define the final equipment configuration.
The series capacity range provides a starting point for equipment selection. Final configuration is reviewed against the intended test application and required output conditions.



What Should Be Confirmed Before Quotation?
Providing the following project information helps SDACME review the required power-source configuration before preparing a quotation.
Define what transformer test must be performed before selecting the required test power source.
Review available input power together with the required voltage, frequency, phase and output conditions.
The selected equipment configuration is defined after the actual transformer and test requirements are reviewed.
Transformer rated capacity alone does not define the required power supply rating. Test type, test voltage, frequency, transformer characteristics and the complete test arrangement should be reviewed together before final equipment selection.
Provide the available project information and SDACME will review the appropriate partial discharge-free power supply configuration for quotation.
Local HMI Monitoring with Integrated Electrical Protection
The partial discharge-free power supply provides local operating visibility for key electrical parameters together with integrated protection functions for controlled transformer test power operation.
Key Electrical Parameters at the Operator Interface
The local interface provides the operator with the principal electrical information required to monitor the configured test power output during operation.

The reference configuration uses a color touchscreen for local operation and parameter monitoring. Final interface details follow the selected equipment configuration.
Electrical Protection Functions
Protection functions are integrated into the equipment to support controlled operation under abnormal electrical or thermal conditions.
The operator interface provides local access to the principal operating functions of the configured system.
Operating information and system status are presented to support equipment monitoring during the transformer test process.
The reference technical configuration includes power-failure output and indication functions as part of equipment operation.
Public product information describes the available monitoring and protection functions. Detailed protection settings, control logic and project-specific operating parameters are defined for the selected equipment configuration.
Manufactured and Factory-Tested for Transformer Test Power Applications
SDACME manufactures partial discharge-free frequency converter systems for transformer test power applications, from cabinet assembly and equipment integration through factory verification and preparation for delivery.

Actual workshop equipment showing cabinet assembly and manufacturing work in progress.
From Equipment Assembly to Factory Verification
Each project begins with the required transformer test duty and electrical configuration. The equipment is then prepared around the selected capacity, test conditions and project interfaces.
- Power conversion cabinet assembly
- Configured equipment integration
- Local control and monitoring interface
- Factory equipment verification
- Preparation for project delivery

Workshop view showing an actual equipment configuration during the manufacturing stage.

Actual factory equipment demonstrates manufacturing activity across different cabinet configurations.

Factory testing provides verification of the configured equipment before shipment and project use.
From Requirement Review to Factory Test
The manufacturing process follows the selected transformer test requirement and equipment configuration through assembly, integration and factory verification.
Transformer information, test duty and required electrical conditions are reviewed before equipment configuration.
Power supply cabinets are assembled according to the selected project configuration.
Control, monitoring and the required equipment functions are integrated into the configured system.
The completed equipment is checked and tested before preparation for delivery.
Factory test documentation is included with the referenced partial discharge-free frequency converter equipment package.
From Test Environment to Equipment Delivery
Real equipment, transformer test environments and delivery preparation provide practical evidence behind the SDACME partial discharge-free power supply product line.

Equipment Installation
Actual partial discharge-free power supply equipment shown in an installation environment.

High-Voltage Transformer Test Setup
Real transformer-related test environment showing the type of application in which controlled test power equipment is used.

2000 kVA Reference Equipment
Actual large-capacity equipment providing a physical reference within the stated 5–2000 kVA product range.

Equipment Prepared for Shipment
Finished power supply equipment packed and prepared for project delivery.
What These Images Demonstrate
The product is represented by actual manufactured systems rather than conceptual product renderings.
Test-area evidence supports the product positioning as a power source for transformer test applications.
Combined with the factory evidence above, the page documents the path from manufacturing through testing and shipment preparation.
The equipment shown represents real manufactured and test-related examples. Final capacity, electrical interfaces and test conditions are defined according to the selected project configuration.
Partial Discharge-Free Power Supply FAQ
Key answers for transformer manufacturers, test laboratories and engineering teams evaluating a variable-frequency AC power source for partial-discharge and induced-voltage testing.
What is a partial discharge-free power supply?
A partial discharge-free power supply is a variable-frequency AC test power source used in transformer test arrangements that require controlled voltage, frequency, waveform and electrical isolation.
SDACME equipment is intended to provide the excitation power required for transformer partial-discharge and induced-voltage test applications, with the final configuration selected around the required test duty.
Is a partial discharge-free power supply the same as a partial-discharge detector?
No. The power supply provides the AC excitation source; the partial-discharge detector or measurement system performs the actual PD measurement.
In a complete transformer test arrangement, the power source, measurement equipment, transformer connections and other test components work together according to the selected test method.
What capacity range is available?
The stated SDACME partial discharge-free frequency converter series covers a capacity range of 5 kVA to 2000 kVA.
Final equipment capacity is selected from the complete transformer test requirement rather than transformer rated capacity alone.
What output voltage and frequency are available?
The reference electrical configuration specifies an output-voltage range of 0–1000 V line-to-line and an output-frequency range of 45–200 Hz.
Final electrical interfaces and required operating conditions are reviewed against the selected equipment configuration and the intended transformer test.
What transformer tests can the power supply support?
The primary applications are transformer partial-discharge testing and induced-withstand-voltage testing.
The technical solution also identifies applicable power-supply use for selected transformer no-load loss, load and temperature-rise test duties.
- Partial discharge testing
- Induced withstand voltage testing
- No-load loss testing
- Load testing
- Temperature-rise testing
Why does the test power source matter in transformer partial-discharge testing?
The excitation source establishes the electrical conditions applied to the transformer during the test.
Output waveform, voltage and frequency stability, electrical isolation and output conditioning are therefore important considerations when selecting power equipment for a sensitive transformer test arrangement.
What information should I provide for configuration and quotation?
Start with the transformer information, intended test duty and the required electrical conditions.
- Test type
- Transformer rated capacity
- Transformer voltage level
- Available input voltage, frequency and phase
- Required output voltage
- Required test frequency
- Existing test equipment or test arrangement, if applicable
SDACME can then review the required partial discharge-free power supply configuration before quotation.
Need a Partial Discharge-Free Power Supply for Your Transformer Test?
Send SDACME your transformer test requirements and required electrical conditions. We will review the application and prepare the appropriate power-supply configuration for quotation.
Start with the Available Project Information
You do not need to define the complete power-supply configuration before contacting us. The following information provides a practical starting point for technical review.
Request Your Project Configuration
SDACME manufactures partial discharge-free power supplies for transformer test applications. Submit the project conditions for configuration review and quotation.
