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Torsional vibrations phenomena are self-excited vibrations that occur in the wheelset of railway powertrains due to the counter-phase oscillation of both wheels. Long-lasting events of this type may lead to the catastrophic failures. Therefore, torsional vibration suppression and mitigation methods have drawn significant attention from the railway industry in the recent few years. Conventional vibration suppression methods reduce motor torque once the oscillation is detected. However, this can result in trip delays. Design of methods which do not compromise the traction capability is challenging. This paper proposes a novel torsional vibration suppression method using a Proportional-Resonant (PR) controller. The proposed method is insensitive to mechanical drive-train parameter variation neither requires adding new sensors to the wheelset. The method requires previous knowledge of the natural frequency of the wheelset torsional mode but this significantly reduces the implementation complexity suffered by other anti-vibration methods. Furthermore, the method will be shown to provide reduced sensitivity to slip velocities and wheelrail conditions.INDEX TERMS Railway traction drives, torsional vibrations, slip-stick phenomenon, slip control, fieldoriented control, proportional-resonant controller.

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Power Quality (PQ) has been an important topic since the creation of distribution systems. The deployment of the Advanced Metering Infrastructure (AMI) provided an important tool to measure the PQ of the electric power in the consumption points. One of the smallest secondary distribution systems in terms of power consumption is the single-phase split-phase system (120 V/240 V) that countries such as the United States, Canada, and some countries of central and south America have. Due to its size, this secondary distribution system is more prone to PQ issues. To that end, an experimental set-up was built by the authors so the distribution system from the Low Voltage (LV) transformer to the final appliances of the different houses was emulated. The aim is to capture the currents and voltages observed by the smart meter located at the entrance of the house and look for the different responses. A combination of real and dummy loads was installed in the set-up, so real noise could also be simulated. The set-up was totally automated by an industrial controller and relays, and it produced a very detailed dataset that could be used for multiple purposes.