UniGear ZS3.2 Medium-Voltage Air-Insulated Switchgear

Summary

UniGear ZS3.2 is threephase, metalenclosed, airinsulated, LSC2B switchgear and all the panels are factoryassembled, typetested and suitable for indoor applications up to 40.5 kV. The panels are designed as withdrawable modules and are fitted with a single busbar system. The withdrawable parts are equipped with circuitbreakers.

Details of the technical design and configuration of individual switchgears can be found in the relevant order documents, such as the technical data, detailed equipment lists for the individual panels, comprehensive circuit documentation and etc.

Standards and specifications

UniGear ZS3.2 comply with the standards and specifications for factory assembled, metalenclosed and type tested high voltage switchgear to IEC publications 62271200, 622711 and GB/T 3906. In addition, in accordance with IEC 60529, the switchgear panels have the following degrees of protection:

· IP 4X for the enclosure and IP 2X for the partitions.

All other corresponding IEC publications, national or local safety at work regulations and safety regulations for production materials must be followed during erection and operation of these systems. Above and beyond this, the orderrelated data from ABB Xiamen Switchgear Co., Ltd. are to be taken into account.

Operating conditions

Normal operating conditions

The panels are fundamentally designed for the normal service conditions for indoor switchgears IEC publication 62271200. The following limit values, among others, apply:

· Ambient temperature: Maximum +40°C; Minimum15°C

· Humidity

· Maximum 24 h average of relative humidity 95%

· Maximum 24 h average of water vapour pressure 2.2 kPa

· Maximum monthly average of relative Humidity 90%

· Maximum monthly average of water vapour pressure 1.8 kPa

· The normal operational altitude is up to 1000 m above sea level.

· The indoor ambient conditions are free of significant pollution, such as dust, smoke, corrosive and/or flammable gases, vapors or salt, etc.

Special service conditions

According to IEC 622711 and IEC 62271200, the manufacturer and user may agree on special service conditions which deviate from the normal service conditions. The manufacturer must be consulted in advance about each special service conditions.

· At site altitudes above 1000 m, the effects of the reduction in dielectric strength of the air on the insulation level are to be taken into account.

· Increased ambient temperatures must be compensated for in the design of the busbars and teeoff bars, or the current carrying capacity will be limited. Heat dissipation in the switchgear panel can be assisted by fitting additional ventilation facilities.

Product features

Standard design

Based on the innovative SmarTube technology, full range of air clearance above 300 mm in a panel width of 1400 mm.

Safety upgrade

Antidumping mechanism of circuit breaker truck protects the personal safety during operation and maintenance, and the motorized circuit breaker truck and earthing switch help the new energy power plant completely realize the unattended substation.

Performance improvement

Whole panel has passed the level 2 ageing test, which belongs to Class 2 of enclosed switchgear for use in special service conditions with respect to condensation and pollution. The partial discharge level is very low. ET1 earthing switch has the withstand shortcircuit making operation up to 5 times, and the required operating torque is highly reduced.

Smart switchgear

The innovative SmarTube thirdgeneration IoT technology, the combination of embedded sensor technology and powerful edge computing capability realize comprehensive intelligent sensing of switchgear temperature rise, motion, position and environment. The temperature rise algorithm based on artificial intelligence can personalize the learning of the temperature rise characteristics of the switchgear after it is put into operation, automatically adapt to various panel variants and widths, changes in the operation mode of adjacent panels and environmental fluctuations around the switchgear, and fit an accurate temperature rise prediction model in a datadriven manner. Artificial intelligence technology helps users to more accurately grasp the operating status of the switchgear, reduce operating costs, make better decisions, and improve power supply reliability and continuity.

Main functions

1. Independent compartment structure: The panel is divided into four compartments: circuitbreaker compartment, busbar compartment, cable connection compartment, low voltage compartment. The enclosure and internal partitions adopt 2 mm thickness aluminiumzink coated sheet steel. Three highvoltage compartments are fitted with secured pressure relief plates located at the top, which will open upward under overpressure caused by internal arc faults. When circuitbreaker truck is removed, metal shutter will automatically drop to closed position, the spout and fixed contact are fully shielded to achieve PMlevel compartment isolation. Low voltage compartment is completely separated from highvoltage compartment with shockproof and fireproof performance. Beside feeder/incoming panel, there are metering panel, bus riser panel, bustie panel and other panel types.

2. Multidimensional misoperation prevention interlock system: Including panel internal interlocking, door interlocking and interlocks between panels.

· The withdrawable part can only be moved when circuitbreaker and earthing switch are off; circuitbreaker can only be closed under test or service position.

· Earthing switch closing is interlocked with the position of withdrawable part; when earthing switch is closed, withdrawable part cannot be pushed into service position.

· Circuitbreaker compartment door cannot be opened when withdrawable part is at service position; cable compartment rear door cannot be opened if earthing switch is open.

· Multiple padlock positions are reserved for shutter, earthing switch operating shaft, racking slot and cabinet doors; emergency unlocking bolts are available for compartment doors.

3. Primary circuit switching, fault breaking, earthing and overvoltage protection: Equipped with withdrawable VD4 vacuum circuitbreaker for switching, fault breaking and autoreclosing. ET1 earthing switch provides protective earthing for maintenance. Current transformers and voltage transformers are installed in cable compartment for signal acquisition. MWK/MWD surge arresters protect primary equipment insulation against lightning and switching overvoltages. Multiple parallel cables can be connected inside cable connection compartment.

4. Secondary circuit protection, measurement and status monitoring: UniGear ZS3.2 is principally fitted with ABB Relion series comprehensive protective relay which implements IEC 61850 standard. Measuring instruments can be configured according to user requirements. ABB auxiliary switches and LED position indicators are adopted. Operation power is protected by miniature air circuitbreaker, lowvoltage fuses are principally not used. Metal secondary wiring trough with sufficient space is arranged inside lowvoltage compartment.

5. Optional intelligent sensing function: Temperature sensors can be installed on teeoff bar, fixed contact and cable connection bar (ABB Smart solution on request), to realize intelligent sensing and AI temperaturerise prediction.

Specification parameters

Main electrical data (Table 2/1 Main parameters)

Note: ¹) Up to 48 kV for certain region with selected variants. ²) Forced air cooling is used when the rated current is 3150 A. ³) Take the shortcircuit withstand capability of the instrument transformers into account separately. ⁴) Special DC voltages on request.