SUMMARYIn recent years, several papers have dealt with eccentricity fault diagnosis considering the cage-induction machine while wound machine type has not been studied as a case. In this paper, eccentricity fault is studied based on the current/torque signature considering modified winding function approach (MWFA). A novel discrete model is introduced, and eccentricity fault is evaluated in both static and dynamic cases. To reach this aim, a numerical model is presented for slot openings, distributed windings and air-gap, thereby computing the machine's inductances using MWFA. Power spectral density (PSD) of stator's current and machine's vibration are analyzed for static and dynamic eccentricity diagnosis and the finite element method (FEM) is utilized to precisely verify the proposed method. Mathematical-based model with consideration of both slot openings and non-sinusoidal winding function effects are the advantages of the proposed method over the previous researches in this field. Moreover, proposed method, which is based on mathematical modeling, could be easily applied to other types of electrical machines, and this feature is regarded as another key point of this paper.

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Recently, hydraulic engine mounts have been used widely as an effective vibration isolator in automotive engines. They consist of two fluid chambers connected by an inertia track path and a decoupler mechanism with a floating plate. An ideal hydraulic mount should have high stiffness and damping at low frequencies and at high frequencies should act as a good isolator. Despite their acceptable performance, there are some drawbacks including switching, nonlinear behavior of the decoupler plate at low frequencies, and occurrence of the resonance due to the passage of the fluid through the decoupler in the high-frequency range. This paper proposes a new decoupler mechanism where the floating decoupler plate is replaced with a membrane where its tension could be controlled considering the operational frequency. Considering the discrete model of the operating fluid and the continuous model of the membrane, governing equations of the system are derived. By increasing the membrane tension at low frequencies, it is shown that the desired dynamic stiffness and damping can be achieved and the nonlinear switching behavior is eliminated. At the same time, by decreasing the membrane tension at high frequencies, it is shown that there is a significant increase in system compliance, resulting in better isolation. Results also show that the membrane replacement also eliminates the fluid resonances at high frequencies. Finally, the two-objective optimization method of the genetic algorithm is employed to find the optimal values of the membrane tension and the mount parameters. The results show that the proposed mechanism can be used as a suitable alternative to the conventional hydraulic mounts.

A combined power source including superconductor magnetic energy storage system (SMES) and photovoltaic (PV) systems has been considered for distributed generation system as a hybrid power source in this research. Both power sources have been connected to power grid and some controllers have been designed for power injection control. The SMES system can be in charging mode via PV system and power grid. Moreover, power injection controller has been designed for tuning of produced power of PV and SMES system. For this aim, a DC/DC converter has been connected to PV system and a bi-directional-three-level chopper has been used for SMES. PV power control has been based on the DC/DC converter control and the chopper control has been used for SMES power control. On the other hands, inverter control has been confirmed for injection of active/reactive power from distributed generation system to power grid. Proposal of a new scheme and design of a novel controller, are the advantages of this research. Finally, a series of simulation results have been shown.Keywords PV system · SMES · Bi-directional-three-level chopper · Chopper switching · Three level inverter · Power injection List of symbols AThe ideal coefficient related to photovoltaic cell model The current source related to photovoltaic system model I SC The short circuit current of the diode used in the photovoltaic cell model I RS The short reversed saturated current of the diode used in the photovoltaic cell model K Boltzmann constant K IThe temperature effect coefficient on the current of used diode in the photovoltaic cell model N sThe number of series cells in photovoltaic package N pThe number of parallel cells in photovoltaic package P PVThe power of photovoltaic system P T rThe transmitted active power from the distributed generation system into the power grid P PV -Max The maximum accessible power from the photovoltaic system qThe numerical value of electron Q T rThe transmitted reactive power from the distributed generation system into the power grid R sThe series resistor of each diode in photovoltaic package R shThe parallel resistor of each diode in photovoltaic package T cThe temperature of the environment in photovoltaic system T re fThe reference temperature in photovoltaic system model V c1 , V c2 DC-link capacitors voltage V DC

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