A SYSTEM FOR QUENCH DETECTION IN THE SUPERCONDUCTING FIELD WINDING OF A SYNCHRONOUS GENERATOR

In order to protect the superconducting field winding of a model synchronous generator against thermal destruction during a quench, the voltage differentials between two parts of the field winding are measured. In practice this method of quench detection is not good enough, as contrary to theory normal dynamic operation in itself causes significant voltage differentials. The behaviour of electrical transmissions within the exicited field- and armature circuits producing voltage differentials are identified. A process computer is used to simulate these voltage differentials in real time. It is also necessary to use an "Observer" to compensate for the time drift which occurs between the real winding behaviour and the digital parallel model. Only significant deviations between measured and simulated signals indicate a quench and release an emergency shutdown of the generator.