Preventing Voltage Collapse

Preventing Voltage Collapse is a 10-hour, nine-module online program in which students use simulations to learn the fundamental principles. Students are guided through a series of simulated operating exercises with increasing level of difficulty. In the early modules students observe and record system conditions and implement specfic operating orders. In later modules student are faced with major system outages and must use critical thinking skills to analyze operating condition, set priorites for problems to be solved, analyze and implement control options with the simulated SCADA and AGC interfaces, observe the system response in real-time and adjust the operating tactics.  

Fundamentals that are covered include: 

Managing the MW flows and MVAR reserves in a simulated transmission system; maintaining the system within SOLs and IROLs to prevent voltage collapse as multiple contingencies occur; the principles of voltage collapse including nominal and actual loads, generator MVAR capability characteristics, line surge impedance loading, MVAR characteristics of capacitors and reactors and transformer tap regulation with weak and strong sources; effects of mistakes that cause line overloads, voltage violations, cascading outages and system collapse.

This is a 10 -hour online program with an online post test and 8 sets of Simulator Exercises. The nine modules are:

PVC-501 A Voltage Collapse Scenario: Principles of voltage collapse including nominal and actual loads, types of voltage collapse, P-V curves;  generator voltage regulation/MVAR limits, bus loads, weak bus and strong bus; observation of a system at the edge of voltage collapse; control actions that can precipitate or prevent the voltage collapse.

PVC-502 Voltage and MVAR Characteristics of Generators: Voltage and Mvar characteristics of generators; effects of generators reaching their maximum and minimum Mvar limits; bus voltages and generator Mvar output when one generator raises its regulating voltage and when a group of generators raise their regulating voltages in unison.

PVC-503 Voltage and MVAR Characterisics of Transmssion Lines: Surge Impedance Loading (SIL) characteristics of transmission lines; MVAR demands of the line at various MW loading levels.

PVC-504 Transmission Lines with Radial Loads: Lines loaded in a radial configuration until voltage collapse occurs; plotting the P-V curve for the line; effects of adding inductive MVARs and capacitive MVARs to the MW load.

PVC-505 Shunt Capacitors and Reactors: Voltage and MVAR characteristics of shunt capacitors and shunt reactors; relationship between capacitor MAVR output and bus voltage; importance of getting capacitors on early in the morning before transformer taps raise the voltages and Mvar demands of the lower voltage networks.

PVC-506 Transformers - Part I - Principles of Operation: Principles, design and operating charateristics of transformers including: transformer windings, turns ratios, tap changers, operation of taps with strong and weak primary buses, MVAR demands and MVAR flows and damaging effects of over-voltages.

PVC-507 Transformers - Part II - Exercises: Simulation of effects observed in the previous module; recording voltages of the primary and secondary buses; runaway tap situations.

PVC-508 Voltage Stability Margins: Methods for determining when a system is prone to voltage collapse; MVAR margins using V-Q curves with increasing bus reactive load; MW margins using the P-V curves with increasing power transfers or area load; application of these methods and use of the simulator to measure V-Q curves and P-V curves.

PVC-509 Preventative and Remedial Actions: Iterative steps used by experienced operator to make real-time decisions including cue observation, pattern recognition, candidate action scripts and mental simulation with appropriate mental models; system operation during a major storm event; response to real-time events; corrective actions.