Methods and systems for real-time monitoring of the insulation state of wind-powered generator windings

A system comprising:

• (a) a wind turbine;
• (b) a generator comprising electrical insulation;
• (c) a converter;
• (d) an electrical variables measuring device that is configured and arranged to measure a voltage and a current in a rotor and a stator of the generator;
• (e) an electrical network, wherein the wind turbine is connected to the electrical network via the converter;
• (f) a sensor assembly comprising a first pair of sensors disposed on a first side of the generator and a second pair of sensors disposed on an opposite side of the generator, wherein the first pair of sensors comprises a first sensor configured and arranged to measure radial-vertical vibration in the first side of the generator and a second sensor configured and arranged to measure radial-horizontal vibration in the first side, and wherein the second pair of sensors comprises a third sensor configured and arranged to measure radial-vertical vibration in the opposite side of the generator and a fourth sensor configured and arranged to measure radial-horizontal vibration in the opposite side of the generator;
• (g) a vibration measuring device connected to the sensor assembly;
• (h) a data bus configured and arranged to receive in real-time (i) a data stream of measurements of electrical variables of the generator from the electrical variables measuring device and (ii) a data stream of measurements from the vibration measuring device;
• and
• (i) a computer connected to the data bus configured and arranged to (i) capture, in real-time during a predetermined time period, values of the electrical variables of the generators and values of the radial-vertical and radial-horizontal vibrations of the generator in at least one of the coupling side of the generator and the opposite side of the generator, (ii) obtain in real time a temporal evolution of inverse components of the electrical variables at one or more predetermined frequencies and a temporal evolution of the values of the vibrations at the one or more predetermined frequencies, (iii) identify a possible insulation fault in the generator when either the inverse component of the electrical variables or one of the radial-vertical and radial-horizontal vibration at one of the one or more predetermined frequencies exceeds an absolute threshold or a temporal increase threshold pre-set;
• wherein the one or more predetermined frequencies comprises (a) a frequency at which an insulation fault in the generator produces an imbalance of voltage and current variables in the rotor and stator that leads to an increase in an inverse component of said variables, and (b) a frequency at which an imbalance of currents caused by an insulation fault in the generator produces an electromagnetic imbalance that results in vibration of the generator such that the system can be used to identify an incipient fault in the electrical insulation of the generator.