... simplicity, and explanatory richness of thatvery basic drawing, we can appreciate why phasors are an electrical engineer’smost essential tool for visualizing a. c. power. 84 AC POWER &CHAPTER ... such variables as voltage, frequency, real and reactive power, and stressing in particular the interaction among generators, which is fundamentalto the overall performance and stability of an alternating ... case of pumped hydroelectric storage or tidal power plants, where large water pumps are oper-ated reversibly as turbine generators.85 Electric Power Systems: A Conceptual Introduction, by Alexandra...