Stabilizing Condition of Grid-Connected VSC as Affected by Phase Locked Loop (PLL)
Yujun Li, Zhengchun Du
Abstract
The small signal stability of the system that one single VSC is connected to an infinite source via the line is investigated in this letter. An analytical stabilizing condition for such system is derived based on the linearized model. It builds up the relationship between controller parameters, electrical distance, and system operating points for ensuring system stability. It is founded that both large and small proportional gains of PLL may lead to the system instability. Moreover, the system is unstable once the integral gain of PLL exceeds one critical value.
Topics & Concepts
Phase-locked loopControl theory (sociology)Controller (irrigation)Stability (learning theory)InstabilityGridElectric power systemLoop (graph theory)Control systemSIGNAL (programming language)EngineeringMathematicsPhase (matter)Computer sciencePower (physics)PhysicsControl (management)MechanicsMachine learningArtificial intelligenceGeometryQuantum mechanicsElectrical engineeringBiologyCombinatoricsAgronomyProgramming languageMicrogrid Control and OptimizationPower System Optimization and StabilityPower Systems and Renewable Energy