Electromagnetic Transient (EMT) Study Related to Shunt Reactors and Current Limiting Reactors

For the purpose of connecting new Syrdarya CCGT power plant (3000MW) to Uzbekistan’s power system installing of additional equipment, such as shunt reactors and current limiting reactors was considered as necessary in previous phases of project development.

In order to define necessary characteristics of such equipment and its corresponding circuit breakers specific analyses had to be carried out. For shunt reactors load flow analysis was conducted on light load conditions of Uzbekistan’s power system in order to analyze its effect on overall voltage profile in the vicinity of new CCGT power plant. Additionally, electromagnetic transient (EMT) simulations, such as line energization and re-energization, were carried out to investigate potential requirements for shunt reactor and its corresponding circuit breaker. For fault current limitation current limiting reactors were proposed in previous phases of the project development. Within this study switching transient analyses were carried out in order to assess the potential switching overvoltages and eventually propose additional requirements for associated circuit breakers, such as usage of snubbers, pre-insertion-resistors, transient recovery voltage and rate of rise of recovery voltage characteristics. Additionally, a ferroresonance phenomenon was investigated and also the harmonic content of generated switching overvoltages was identified. All analyses within this Study were performed by using DIgSILENT PowerFactory software.

Type of services provided:

• Shunt reactor related studies:
  • Analyzing the effect of shunt reactor during light load conditions
  • Developing EMT model for switching studies related to installment of shunt reactors
  • Analysing switching overvoltages related to connection of shunt reactors and proposal for its additional charactersistics
• Current limiting reactor studies:
  • Developing EMT model for switching studies related to installment of current limiting reactors
  • Switching overvoltage analysis
  • Ferroresonance analysis
  • Power quality analysis