Browse the services offered by REIVAX:

Power System Studies Technical Assistance Modeling Training

Power System Studies

Using software tools consolidated in the market (DIGSILENT POWER FACTORY, CEPEL ANATEM, REIVAX SEC, among others), electromechanical stability studies are developed for different types of power plants (hydroelectric, photovoltaic, wind power, thermoelectric) considering controllers and machines from different manufacturers.

The validation of the mathematical models against the curves obtained from field tests is carried out following the determinations of the Brazilian System Operator (ONS standard report).

The tuning of control loops for Digital Hydro Governors, Voltage Regulators and Power System Stabilizers can be simulated prior to commissioning new equipment, both in retrofits and new power plants.


  • SIN Access Studies, as recommended by ONS;
  • Identification of generators and turbines (hydro, thermal, wind);
  • Mathematical modeling of controllers (Digital Hydro Governor, Voltage regulator, Power System Stabilizer, Joint Control);
  • Controller performance evaluation;
  • Power Flow Study (CEPEL ANAREDE);
  • Stability Study (CEPEL ANATEM);
  • Small Signal Stability Study (DIGSILENT POWER FACTORY);
  • Electromagnetic Transient Study (ATP, PSCAD): Energization, Insulation Coordination;
  • Mathematical modeling of electrical systems (Solar Plants, Wind Power Plants, Static Condensers and HVDC Systems).

Selectivity and Protection Studies (CEPEL ANAFAS)

  • Determine the setting order of the protection devices;
  • Increase the equipment’s protection capability for possible failures;
  • Ensure proper coordination between protective devices;
  • Increase plant reliability with proper adjustments;
  • Electrical System Protection Studies.

Short-circuit studies (CEPEL ANAFAS)

  • Obtain the three-phase and single-phase short-circuit levels and the X/R ratio for the calculated fault locations;
  • Evaluation of the effects of different types of short circuit on the system voltage profile, identifying the areas of the system where faults can result in unacceptable voltage sags;
  • Equipment dimensioning: circuit breakers, switches, busbars, cables, transmission lines, transformers, installation grounding, etc.;
  • Specification of current transformers, blocking coils, and protection systems;
  • Grid equivalent calculation;
  • Checking the evolution of short-circuit levels.

Technical Support Services

REIVAX’s vast experience allows its professionals to work in the maintenance, commissioning, and adjustment of controllers.
The services are provided in new and legacy REIVAX equipment, or even controllers from other manufacturers.

Plant modernization processes may demand technical support in the electrical and mechanical areas, in the specification of new equipment, instrument replacement, equipment and cable testing.

Plant digitization processes create major challenges both in technical issues, linked to equipment specification, as well as in human resource optimization.

REIVAX has a highly qualified team to work both in the factory and in the field. It has more than 30 years’ experience with the development, design, manufacturing and commissioning of control, protection and automation systems.

Count on REIVAX’s Technical Support.

  • Field tests: signal acquisition during decommissioning of generating units, prior to modernization;
  • Technical follow-up during the return of generating units after scheduled shutdowns for periodic maintenance;
  • Preparation of technical specifications for equipment specification during plant modernization processes;
  • Preventive maintenance of Digital Hydro Governor s, including hydraulic systems;
  • Preventive maintenance of voltage regulators, including thyristor bridges/IGBTs and field contactors;
  • Commissioning of Automation and Protection Systems;
  • Proprietary Engineering, standing beside the client regarding service and equipment suppliers;
  • Execution of index test assays;
  • Field tests to diagnose excessive vibration in the generating unit;
  • Automation design for photovoltaic, hydroelectric, and wind power plants;
  • Automation network auditing, configuration, and maintenance;
  • Performance auditing of solar, wind and hydroelectric power plants;
  • Monitoring and predictive maintenance in solar power plants.


In power system planning and expansion studies, suitable models of the controllers (Combined Excitation System and Speed Governor s) and the generating units (generators and turbines) are required.

Such models, provided by the manufacturers, require validation with field tests, in order to confirm that the model properly represents the physical system.

Standardized controller models can be used in the studies, with the parameters being validated through field tests. However, it’s possible to survey the controller transfer feature that doesn’t fit the standard models. After field tests are performed, the curves obtained are compared with the simulated curves.

REIVAX has more than 30 years’ experience in the modeling of machines and controllers. The block diagrams can be delivered in different data files, according to the tool used: CEPEL ANATEM, DIGSILENT POWER FACTORY, SIEMENS PSS-E, ENGIE EUROSTAG, MATLAB, among others.

Advantages of Mathematical Modeling of Machines and Controllers with Field Trials:

  • Detection of improper settings of the excitation system, limiters and PSS;
  • Detection of problems of inadequate coordination between the control system and protections;
  • Detection of improper unit operation (e.g., unit not performing primary regulation, power factor control, among others);
  • Knowledge of generator operating limits;
  • Coordination of the generator protection with the excitation system limiters;
  • Operational limits of the synchronous generator;
  • Voltage regulator settings (VRS) and dynamic limiters;
  • Power System Stabilizer Tuning;
  • Voltage regulator reactive compensator adjustment;
  • Digital Hydro Governor  control and actuators adjustment;
  • Analysis of the unit’s control mode.


REIVAX’s vast experience in the development, design, manufacturing, and commissioning of control, protection, and automation systems puts the company’s professionals at a level capable of delivering high-level technical training.

During REIVAX’s training, the different electric sector’s stakeholders, linked to the Project, Construction, Operation, Maintenance, among others, will receive theoretical and practical information, helping them perform their activities.

Courses in the in-person at the client’s headquarters, in-person at REIVAX, or distance learning (Online) modalities allow clients to be trained as conveniently as possible.

Complete courses or even mini-courses allow the discussion of relevant topics during new power plant or retrofit projects. Different countries have already hosted REIVAX Technical Seminars, discussing topics of interest: Chile (2015 and 2017), Peru (2015 and 2017), Costa Rica (2016), Colombia (2017), Mexico (2018), Argentina (2018), as well as different clients in Brazil (CTG Brazil, Neoenergia, Elera, Furnas, Aliança Energia, CHESF, CELESC, COPREL, ENEL, ELETRONUCLEAR, PETROBRAS, CEMIG, ATIAIA, LIGHT), among others.

Be qualified with REIVAX courses!

  • Courses in Regulation Systems for Hydropower Plants;
  • Course in Regulation Systems for Thermal Power Plants;
  • Operation and Maintenance Training for REIVAX products (RTX POWER, RVX POWER, RTVX POWER, etc.), including legacy products (RVX300, RTX400, RTVX100, etc.);
  • Training in the programming of POWER platform equipment;
  • Simulation training using electrical study tools, such as CEPEL ANAREDE, CEPEL ANATEM, DIGSILENT POWER FACTORY, REIVAX SEC, etc.;
  • Hydraulic Systems for Hydroelectric Power Plants;
  • Webinars on control systems for solar, hydropower, and hybrid power plants.