- The project represented an investment of approximately US$ 56 million and involved the coordinated work of more than 45 companies and almost 1,000 professionals from 12 different nationalities throughout its various phases.
The project aimed to optimize the distribution of reactive power flow and improve the voltage profile of the Nueva Pan de Azúcar-Polpaico section of the Cardones-Polpaico line. This was achieved by energizing a modern SVCPLUS in 500 kV at the substation located in the Coquimbo region, providing greater reliability to the system.
The project, called “Expansion Work Supreme Decree No. 422 of 2017 of the Ministry of Energy – Reactive Compensation in the 2×500 kV Nueva Pan de Azúcar – Polpaico line,” was awarded to ISA GROUP’s subsidiary and represented an investment of approximately US$ 56 million. The project involved the coordinated work of more than 45 companies and almost 1,000 professionals in its different phases, including Siemens Chile Consortium, Siemens Germany, HMV, leading companies in the project, and WSP as technical inspection of the work.
In its first stage, the project involved the installation and energization of a 53/2% series compensation in the Nueva Pan de Azúcar – Polpaico section, located at the Polpaico substation. This was achieved on November 28th, 2020. Afterwards, the series compensation was modified at the Nueva Pan de Azúcar substation to decrease it to 53/2% and energize it, along with all the necessary adjustments to the associated protection and control system, which was accomplished on December 22nd, 2020.
Finally, the last phase was achieved on August 3rd, with the energization of the SVCPLUS at the Nueva Pan de Azúcar 500 kV / 220 kV Electrical Substation, located in the Coquimbo Region, with advanced technology unique in Latin America.
Gonzalo Moreno Herraiz, ISA INTERCHILE Projects Manager, explains that “the reactive dynamic compensation of the Statcom will make the current system operation more flexible by automatically absorbing reactive power, especially during low demand hours, to maintain a regulated voltage value at 500 kV without the need to remove any 500 kV interconnection circuits from service, thus improving system reliability.”
The ISA INTERCHILE engineer specifies that the series compensation system at the Polpaico substation linked to the Nueva Pan de Azúcar substation, and a 500 kV SVCPLUS at this site, “consolidates an effective automatic voltage control strategic node from Los Changos to Polpaico, thereby improving continuous power supply quality and system transient response to severity 6 events in the Extreme Conditions Defense Plan (PDCE).”
Despite the difficulties posed by the pandemic, the coordinated work of ISA INTERCHILE and all the professionals and companies involved allowed for the installation of two fixed reactor banks of 100 MVAr each in the Nueva Pan de Azúcar 19.3 kV busbar in the last stage of the project, an additional shared reserve unit, two fixed reactor banks of 50 MVAr at the 19.3 kV busbar, and an additional shared reserve unit. In addition, two static reactive power compensators of 50 MVAr each of the STATCOM type based on VSC were installed in Nueva Pan de Azúcar, as well as three power transformers (2 main and 1 for fast change), which will achieve a variable operating range of +100/-400 MVAr at the 500 kV busbar.