An Electrochemical Method for Alkalizing the Rotor Cooling Water of a Synchronous Condenser

Rotor cooling water is a pivotal element for the safe operation of a synchronous condenser in an ultrahigh-voltage grid. To decrease the dissolved oxygen and carbon dioxide contents, tremendous efforts have been dedicated to regulating the solution pH and conductivity. The traditional chemical pH adjustment and resin regeneration methods for rotor cooling water alkalization have the disadvantages of high chemical consumption and high operation and maintenance costs. Here, we propose an electrochemical method for alkalizing the rotor cooling water of a synchronous condenser by taking advantage of the accelerating water dissociation feature in bipolar membranes. The experiments with carbon dioxide injected deionized water revealed that water dissociation in bipolar membrane is capable of increasing the solution pH from 4.6 to 5.6 and decreasing the conductivity from 9.5 μS/cm to less than 2.0 μS/cm. It is convenient to increase the solution pH from 6.5 to even 10.0 when real rotor cooling water is used. BP-A-BP is more competitive than BP-C-A-BP for alkalization purposes. The present study also provides a cost-effective and chemical-free technique to precisely control the water quality of the rotor cooling water in a synchronous condenser.