WBZ-IV Intelligent Fully Automatic Transformer Testing System with Fully Automated Control High Accuracy Measurement and Three-Meter Testing Principle

(Note: This system can be fully automated and controlled by a computer; functions such as ratio testing and DC resistance measurement can be performed using portable devices for field operations.)

The main advantages of this system compared to leading solutions in the industry are:

1. This system employs the three-meter testing principle, utilizing three 0.05-class single-phase independent current transformers, which significantly enhances test stability and accuracy (currently, most market solutions employ two current transformers using the two-meter method for measurement).
2. Under test voltage conditions, since the inductive voltage regulator is driven by a motor, there is a buffering effect during voltage regulation—particularly during power-frequency withstand voltage tests and no-load tests. This makes it difficult to accurately control the test voltage. Our company employs variable frequency speed regulation, allowing the motor speed to be manually adjusted as needed. This significantly enhances the accuracy of test data and the stability of voltage boosting.
3. Before initiating the test, simply input the transformer's basic parameters and select the test item; the system will automatically complete the opening/closing operation, lock the voltage regulation data, and upload the results to the computer's test report.
4. Reserve an upgrade outlet for transformers rated above 35 kV to facilitate future upgrades of the test station to accommodate higher voltage-level test specimens.
5. Data monitoring utilizes digital display instruments and no-load testing equipment, with dual digital displays for real-time monitoring.
6. When querying raw data, simply enter the data identifier to automatically retrieve the information.
7. Provide on-site training for laboratory personnel to enable them to operate independently.
8. The measurement and control software system reserves space for upgrading the temperature rise test functionality, allowing the addition of this test feature as needed.

1. This technical specification outlines all aspects of the transformer integrated test bench, including its design, manufacturing, inspection, testing, technical documentation, acceptance, supply and transportation, on-site commissioning, and after-sales service.
2. The products supplied by Huagao Electric are high-quality items that meet the buyer's requirements.
3. The products supplied by the supplier feature stable performance and reliable test data, and are widely used in transformer and power reactor manufacturing and testing enterprises, earning high praise from users.

The technical specifications of the comprehensive transformer testing platform provided by Huagao Electric fully comply with national and power transformer industry standards and specifications. In case of any discrepancies between standards, the higher standard shall prevail.

• GB 1094.1——1996 Power Transformer Part 1: General Principles
• GB 1094.2——1996 Power Transformer Part 2: Temperature Rise
• GB 1094.1——1996 Power Transformer Part 3: Insulation Level, Insulation Testing and External Insulation Air Gap
• GB/T 1094.10——200 Power Transformer Sound Level Measurement
• GB/T 6451——1999 Technical Parameters and Requirements for Three-Phase Oil-Immersed Power Transformers
• GB 6450——1986 Dry-type power transformer
• GB/T 10228_1997 Technical Parameters and Requirements for Dry-Type Power Transformers
• GB/T 15164——1994 Load Guidelines for Oil-Immersed Power Transformers
• GB/T 507——2002 Insulating Oil Breakdown Voltage Measurement Method

Conduct visual inspection and measurement of the structural style, external dimensions, and manufacturing dimensions of the tower; inspect the internal equipment layout, cable routing, installation techniques, and surface coatings within the screen, and document the findings in writing.

All subsequent tests were conducted in accordance with the relevant IEC 60076-1 to 60076-5 standards "Power Transformers" and IEC 60726 "Dry-type Power Transformers". The test items are listed in the table below:

• 1600–20000 kVA
• High-side rated voltage: 35 kV–38.5 kV
• Low-voltage side rated voltage: 0.4 kV–10 kV
• Impedance: 4–8%

• 30–3150 kVA; Special transformer capacity: 50–6000 kVA
• High-side rated voltage: 10 kV; Low-side rated voltage: 0.4 kV–4 kV; impedance: 4–6%

Factory test requirements for oil-immersed transformers, dry-type transformers, amorphous alloy transformers, combined transformers, pre-assembled transformers, variable-capacity and voltage transformers, dual-split transformers, and rectifier transformers. (Designed for maximum capacity and maximum current, with an output current of 200 A and a maximum output voltage of 22 kV.)

1. The entire testing system ensures both the safety of test personnel and the reliability of equipment operation.
2. Comprehensive overvoltage and current protection
3. The spatial layout is well-designed with clear and organized wiring (all components and connections bear permanent identification markings, and all contactors in the control system are manufactured by renowned domestic brands).

The instrument fully utilizes microcomputer data processing technology, directly inputting measurement results into the microcontroller for calculation, thereby eliminating the need for manual formula substitution. External wiring is uniformly arranged to minimize manual connections; wire replacement is completed automatically via control buttons on the test bench.

The system fully utilizes the interlocking functions of mechanical and electrical components, integrating them seamlessly with computer software to effectively prevent unintended operations. In other words, if the safety procedures are not followed, the system will refuse to start, thereby ensuring the safety of personnel and equipment.

This system features two independent test calculation and display circuits: 1) Computer-based operation for displaying and printing A4 factory reports; 2) Separate digital display of measurement results via instruments. This design ensures that any single-point failure does not disrupt normal equipment operation or test procedures, while enabling our technical personnel to promptly respond to the site for troubleshooting.

All measurement instruments, meters, and measurement transformers in the system meet the requirements of national standards.

The test console enables remote control of voltage regulators and current transformers; allows configuration of current/voltage range conversion, selection of test items, and overcurrent/oversoltage protection; provides real-time display of no-load loss values, automatic control of induced voltage withstand channels and power-frequency voltage withstand channels, printing functions, and voltage withstand timing measurement.

1. The voltmeter and ammeter on the console both display readings via digital heads. The measurement range of the power voltage meter: 0–650 V; accuracy: Class 0.5 Measurement range of the power current meter: 0–400 A/5 A; Precision: Class 0.5 The measurement range of the voltage regulator's output voltmeter: 0–650 V; accuracy: Class 0.5
2. The three-phase voltage regulator is electrically operated for lifting and lowering via the control panel, and features zero position protection as well as upper and lower limit protection functions. The regulator employs contactless variable frequency speed regulation, eliminating motor inertia-induced over-regulation and enabling precise adjustment capabilities.
3. Both no-load and load test items feature overcurrent protection and overcurrent reset functions;
4. The switching of standard current transformer (CT) settings is performed via the transfer switch on the control panel.
5. The main control panel is equipped with an emergency stop device, allowing for immediate shutdown and disconnection of the main circuit in case of unexpected conditions with the test sample.
6. The main control panel is equipped with a red warning light and an alarm bell. The warning light flashes when the main circuit is activated, and upon completion of the test, pressing the alarm bell button alerts the tester that the test is finished.
7. Components of the complete control system: The first section, the main control console, includes various indicator instruments, an air-load tester, an induction voltage withstand channel, an industrial-frequency voltage withstand channel, a overcurrent relay, and start/stop buttons; the second section comprises a low-voltage test auxiliary control cabinet containing an AC contactor, intermediate relay, circuit breaker, low-voltage current transformer, and a frequency multiplier unit with Y/△ starting; the third section consists of a high-voltage transformer metering cabinet equipped with high-voltage current and voltage transformers.

Appendix 1: Block diagram of 10 kV power transformer no-load and load tests:

Appendix 2: Block diagram of 35 kV power transformer no-load and load tests:

Attachment: Equipment exterior and customer site installation reference images: