The problem
The Mexican power transmission system is vast, and to a high degree, longitudinal in configuration. As the electrical energy consumption in Mexico has grown steadily for most of the recent years, the grid has threatened to be a bottleneck in different scenarios. The principal electricity provider CFE (Comisión Federal de Electricidad) has stayed ahead of difficulties, partly by using FACTS to safeguard the system’s steady-state and dynamic stability under various operating conditions. Specific problems have included difficulties to import enough power to the Mexico City area, difficulties to maintain voltage amplitudes on the Yucatan peninsula and concerns about the transient stability between the nine regional grids in Mexico.
The solution
SVC and Series Compensation has been successfully utilized in the grid for a considerable time. By the end of 1999, a total of nine SVCs supplied by ABB were in operation in various parts of the Mexican power grid, along with several Series Capacitors. The SVCs are connected to critical buses at 400kV, 230kV or 115kV level. The possibility to introduce FACTS on a short notice has allowed CFE to operate the grid without supplementary control schemes, like Automatic Load Shedding or Automatic Generation Trip. Also the construction of new transmission lines has been minimized.