Project features

ACWA is developing a 1,500 MW CCGT project through bilateral agreement with the GoU and signed a 25-year PPA in March 2020 on a BOOT basis. ACWA awarded EPC contract to CGGC, where IDOM is responsible for whole engineering scope. As per the agreement with the GoU, ACWA has to build and transfer 500/220 kV AIS designed for evacuation 3,000 MW power to the transmission grid, 12 bays on 500 kV side and 18 bays on 220 kV side including 2 sets of 3x single phase inter bus autotransformers with capacity of around 501 MVA each group. The AIS is planned to be one of the first digital substations implemented by NEGU (Off-taker).

Services provided

AIS related additional power system studies:

• Shunt reactor (SHR) studies for 500 kV:
  • Analyses of light loading conditions in the grid (Q balance) against overvoltage problems and identification of requirements for SHR;
  • Development of EMTP model in DIgSilent Power Factory;
  • 500 kV transmission line single end tripping/energization studies and identification of requirements for line SHR;
  • Sizing and placement of SHR;
  • Shunt reactors switching transient studies & additional requirements for circuit breakers.
• Current limiting reactor (CLR) studies for 220 kV:
  • Development of EMTP model in DIgSilent Power Factory;
  • Switching transient studies of CLR & additional requirements for circuit breakers;
  • Ferrorezonance studies for CLR in accordance with IEC 61869-102 standard; 
  • Harmonic studies for CLR in accordance with IEC 61000 standard.
• Static and dynamic stability analyses of the grid and emergency control automatism (ECA) selection:
  • Development of preliminary maximum list of ECA equipment (panels) that shall be located at new Syrdarya AIS for evaluation of Control Building Dimension requirements & additional CT&VT cores requirements;
  • Analyse of static and dynamic stability for identified list of controlled interfaces (transfer paths) after connection of new Syrdarya CCGT;
  • Validation of the coefficients of AVR, turbine governor and PSS of the gas and steam turbine generators;
  • Define required functions of ECA and its coordination with already implemented ECA systems in the grid;
  • Develop SLD of ECA location including at remote-end substations;
  • Support during development & approval of study results with NEGU, Off-taker.
• Development of the ToR for the complete 500/220 kV scope for Basic and Detailed design stages: 
  • Defining ToR content along with NEGU and the Client;
  • Developing ToR in line with local regulation and Owner Technical Specification (OTS);
  • Support during approval of ToR with NEGU.

500/220kV AIS Basic & Detail Design Engineering review, adaptation, validation with respect to local codes, standards, norms and regulations:

• Supporting the Client in the content and interface management including remote end substation for the design documentation development;
• Review of design criteria on its compliance with local norms and issuance of recommendations;
• Engineering review, adaptation, validation with respect to local codes, standards, norms and regulations of basic and detailed design documentation, including:
• General Layout and Architectural design;
• Substation Primary and Secondary Electrical networks, Auxiliary power supply;
• Control and Protection;
• Emergency Control Automation;
• SCADA and Telecommunication (incl. CCTV);
• HV transmission line;
• Water Supply and Sewage;
• Civil/Structural Engineering;
• HVAC.
• Supporting the client in obtaining input data and confirmation of critical assumptions with the National Electrical Grid of Uzbekistan (Off-taker) for substation principal electrical scheme, control and protection, SCADA and Telecommunication, System Stability and Emergency Control Automation.
• Advise CGGC/IDOM during construction, providing timely instructions on drawings submission and documents customization and required formatting;
• The interface between the Client and the relevant authorities for the approval of project documentation. Expertise and approval (re-approval) of project documentation for construction on the basis of legislative and other regulatory legal acts of urban planning and construction, in force in Uzbekistan.