I. Scope of electrical preventive testing services: This includes conducting regular inspections or tests on electrical equipment that has been put into operation, in accordance with specified testing conditions (such as prescribed testing equipment, environmental conditions, testing methods, and testing voltage), and testing cycles. The aim is to identify potential hazards in the operating electrical equipment, prevent accidents, or detect damage to the electrical equipment.
It mainly covers the following aspects:
(I) Electrical test
- Power transformer: Test winding insulation resistance, transformation ratio, winding DC resistance, etc., to assess the insulation and internal connection status.
- High-voltage circuit breaker: Test insulation resistance, conductive circuit resistance, opening and closing time and speed, etc., to ensure reliable switch performance.
- Isolating switch: Check the insulation resistance and contact resistance, ensure good contact of the contacts, and ensure that the insulating parts are not damaged.
- Lightning arrester: Measure insulation resistance, DC reference voltage and leakage current, residual voltage, partial discharge capacity, surface temperature distribution, and corona discharge conditions, evaluate lightning protection capability, and ensure accurate detection.
- Power cable: Conduct insulation resistance test and voltage withstand test to identify and address issues such as insulation aging or damage.
- Insulator: Inspect the insulation resistance and check for any cracks or damages that may lead to a decrease in insulation performance.
- Instrument transformers: including voltage transformers and current transformers, testing insulation resistance, transformation ratio, error, etc., to ensure accurate metering and protection functions.
- High-voltage motor: Inspect the insulation resistance and DC resistance of the stator winding, as well as the condition of the rotor winding, to prevent motor failure.
(II) Special value-added services
- Partial discharge detection: Equipped with the HVJF handheld partial discharge tester, it utilizes ultrasonic detection technology to sensitively capture local electrical discharge phenomena caused by bubbles, cracks, or impurities in the internal insulation materials of equipment such as transformers, GIS, cables, switchgear cabinets, etc., accurately determining the extent and location of the discharge.
- Drone line inspection: Equipped with multiple high-performance drones from DJI, the efficiency is 40 times higher than manual inspection, and it supports live-line operations. It can operate in complex terrains and adverse weather conditions (such as natural disasters like snowstorms, earthquakes, landslides, etc.), carrying various sensors to achieve comprehensive and multi-angle inspection. It eliminates the risks of manual high-altitude operations, promptly identifies line defects, and prevents power outages. It reduces labor intensity and management costs, enabling efficient analysis and processing of inspection data.
- Oil Testing: Equipped with a dedicated oil testing laboratory, we have 21 sets of professional testing instruments including the Zhongfen 2000 (touchscreen version) gas chromatograph, ZD2000 fully automatic shaker, and HGJQ203 dielectric strength tester, capable of comprehensively analyzing various oil indicators in the power production process.
II. Scope of power plant commissioning services: This includes a series of systematic commissioning, testing, and adjustments conducted after the construction of the power plant or equipment maintenance, and before its official startup. The aim is to verify whether the power generation equipment and systems meet design requirements and operational standards. Through phased and systematic commissioning, design defects, installation errors, or equipment hazards can be promptly identified, laying the foundation for the official operation of the power plant.
It mainly covers the following aspects:
1. Debugging of standalone equipment
- Power generation equipment: mechanical performance testing (vibration, bearing temperature, etc.) and electrical parameter verification (insulation resistance, stator and rotor DC resistance) of equipment such as steam turbines and generators.
- Auxiliary equipment: start-stop testing, speed adjustment, and operation status inspection of rotating equipment such as feed pumps, circulating water pumps, and fans.
2. Electrical system commissioning
- Generator-transformer unit system: Joint commissioning of the generator and transformer, including synchronization device verification, short-circuit test, and no-load voltage rise test.
- Auxiliary power system: relay protection transmission test for high and low voltage switchgear and auxiliary transformers, and functional verification of automatic bus transfer equipment.
- Power transmission and distribution system: on-off characteristic testing of switchyard equipment (circuit breakers, disconnectors), and performance testing of lightning protection devices (lightning arresters).
- Power transformer: Test the winding insulation resistance, transformation ratio, winding DC resistance, etc., to assess the insulation and internal connection status.
- High-voltage circuit breaker: Test insulation resistance, conductive circuit resistance, opening and closing time and speed, etc., to ensure reliable switch performance.
- Isolating switch: Check the insulation resistance and contact resistance, ensure good contact of the contacts, and ensure that the insulating parts are not damaged.
- Lightning arrester: Measure insulation resistance, DC reference voltage, and leakage current to evaluate lightning protection capability.
- Power cable: Conduct insulation resistance tests and voltage withstand tests to identify and address issues such as cable insulation aging or damage.
- Insulator: Inspect the insulation resistance and check for any cracks or damages that may cause a decline in insulation performance.
- Instrument transformers: including voltage transformers and current transformers, testing insulation resistance, transformation ratio, error, etc., to ensure accurate metering and protection functions.
- High-voltage motor: Inspect the insulation resistance and DC resistance of the stator winding, as well as the condition of the rotor winding, to prevent motor failure.
3. Debugging of thermal automation system
- DCS (Distributed Control System): logic configuration verification, signal transmission accuracy testing, such as calibration of temperature, pressure, and flow sensors.
- Protection and interlocking devices: simulation tests for emergency shutdown circuits such as turbine trip protection and boiler MFT (Main Fuel Trip).
- Automatic regulation system: Commissioning of automatic control functions for boiler water level, steam temperature and pressure, and unit load.
4. Thermal system debugging
- Boiler system: hydrostatic test (to inspect the tightness of pressure-bearing components), boiler ignition test, combustion adjustment (air distribution, fuel quantity optimization).
- Steam turbine system: static/dynamic characteristic test of speed governing system, tightness test of vacuum system, and functional verification of bypass system.
- Auxiliary thermal equipment: pressure and temperature control, as well as heat transfer efficiency testing for heaters, condensers, and deaerators.
5. Environmental protection and auxiliary system debugging
- Desulfurization and denitrification system: testing the chemical reaction efficiency of desulfurization towers and denitrification devices, and verifying that emission indicators (such as SO₂ and NOx concentrations) meet standards.
- Water treatment system: Water quality testing for chemical water preparation equipment, and debugging of anti-scaling/anti-corrosion functions for circulating water systems.
- Ash and slag removal system: pressure testing of ash conveying pipelines, start-stop testing of slag removal equipment, and verification of conveying capacity.
6. Overall joint debugging (full system startup)
- No-load commissioning: Operation testing of the unit without load, such as generator no-load characteristic test and turbine overspeed protection verification.
- On-load commissioning: Optimize operating parameters according to different load conditions (30%, 50%, 100% rated load) to test the coordinated control capability of the unit.
- 168 hours of continuous operation: a test of continuous operation under full load to verify the reliability of the equipment and the stability of the system, until the conditions for production are met.
7. Specialized debugging
- Performance verification after the introduction of new equipment or technological transformation (such as the commissioning of new energy coupling systems and the integration of energy storage devices).