C. E. Capovilla

Performance of a Direct Power Control System Using Coded Wireless OFDM Power Reference Transmissions for Switched Reluctance Aerogenerators in a Smart Grid Scenario

This paper presents a performance analysis of a wireless direct power control system for switched reluctance aerogenerators. Aiming at a smart grid scenario, the utilization of wireless technologies for transmitting control information requires a powerful modulation and error-correction coding schemes to avoid any serious problems to the energetic plant. These transmission errors can cause permanent damages in the components of the turbine and converters, and they can also compromise the quality of the energy delivered to the grid. The performance of the proposed system is investigated in a frequency-selective fading channel, thus enabling a deeper study of the impact of the use of wireless communications for reference signal transmissions. This research demonstrates the operational viability of wireless systems for this type of application, when an appropriate digital modulation and coding techniques are applied.

A wind energy generator for smart grid applications using wireless-coded neuro-fuzzy power control

Wind energy is the major driver to obtain an optimized and efficient use of renewable energy in smart grids. To provide balanced supply, demand, and storage of energy in a much more efficient manner than is done today, smart grids require the employment of an advanced communication infrastructure associated to a robust power control and real-time monitoring systems.Towards this objective, we present a wireless-coded power control scheme for doubly fed induction generators operating at variable speed. The proposed system employs adaptive neuro-fuzzy control, quaternary phase shift-keying modulation, and low-density parity check coding techniques to improve the system robustness and reliability in different propagation conditions for remotely transmitting the power control references from the control center to a given aerogenerator.

A deadbeat direct power control applied to doubly-fed induction aerogenerator under normal and sag voltages conditions

In wind energy systems, doubly-fed induction generator is commonly used. The grid requirements for DFIG operation in an occurrence of low voltage ride-through can damage or destroy the converter or damage the generator and its operation can can help the robustness of the power systems by the injection of reactive power. Thus, this paper proposed a deadbeat direct power control for doubly-fed induction generator during low voltage ride-through (LVRT). The controller was designed using the generator model and it allows active and reactive power control also during a voltage sag. The state variables are the active and reactive power, and the inputs are the rotor voltage vector. The controller has a simple implementation and fast dynamic response. Experimental results are obtained to verify the deadbeat direct power controller operation.

A wireless deadbeat power control for wind power generation systems in smart grid applications

This paper proposes a wireless deadbeat power control scheme employing low density parity check coding for variable speed wind power generation (the wind industry is the huge driver behind the push for super-grids and cross-border infrastructure) to improve system robustness and reliability. The wind energy systems uses a doubly-fed induction generator and a deadbeat control. The performance improvements of the proposed system are investigated in different propagation conditions by using simulations results.

Implementation of a neuro-fuzzy direct torque and reactive power control for DFIM

This paper proposes a Takagi-Sugeno neurofuzzy inference system for direct torque and stator reactive power control applied to a doubly fed induction motor (DFIM). The control variables (d-axis and q-axis rotor voltages) are determined through a control system composed by a neuro-fuzzy inference system and a first order Takagi-Sugeno fuzzy logic controller. Experimental results are presented to validate the controller operation for variable speed under no-load and load conditions and stator reactive power variation under load condition. For this last validation, a PI controller is used to control the rotor speed, thereby its output is used to manipulate the torque in order to follow the demanded speed value.

A wind energy generator for smart grid applications using wireless coding neuro-fuzzy power control

The wind energy generation is the huge driver behind the push for supergrids and cross-border infrastructure for renewable energy systems into smart grids. To provide balance supply, demand, and storage of energy over a region in a much more efficient manner than it is done today, smart grids will need to use an advanced communication infrastructure into a robust control system. Towards this objective, it is proposed in this paper a wireless coding power control employing low density parity check coding to improve system robustness and reliability. For variable speed operation, the wind energy system uses a doubly-fed induction generator and a neuro-fuzzy controller. The performance improvements of the proposed system are investigated in different propagation conditions.

An Adaptive Neuro-Fuzzy Strategy for a Wireless Coded Power Control in Doubly-Fed Induction Aerogenerators

Renewable energy systems and specially wind energy have attracted governmental interests in opposition to energy sources that increase CO2 emissions and cause enormous environmental impact. Recently, the concept of smart grid has been applied to power plants to enable and optimize the generation of energy by efficiently combining wind, solar and tidal. Moreover, the efforts for consolidation and implementation of this new concept through wind energy systems have attracted great interest from the technical community and has been the focus of several recent scientific works [1–3].

Wireless communication applied in a grid tie converter control for renewable sources

This paper proposes a predictive power control for a converter connected to the grid. The power references are sent by a wireless channel with the focus to control renewable sources. The three-phase converter controls the power injected to the grid using a predictive control technique. Simulation results are presented to validate the system operation.

A CMOS LNA Partially Degenerated Topology Proposal Using Active Inductors

This paper presents the design of a CMOS low-noise amplifier (LNA) with partial inductive degeneration using active inductors in 0.35μm technology. Both, the inductor of the partial degeneration and the load inductor, are actives. The inductors configurations are cascode with feedback resistance and Wu folded compact. The LNA has a gain of 13.2dB and a noise figure of 4.7dB at 1.8GHz. The layout has an active area of 0.17mm2. The results are satisfactory, validating the compact design and demonstrating the technical feasibility of this proposed topology.

CMOS Low Noise Amplifier Topology Using Compact Wu Folded Active Inductor

This work presents a topology proposal of a 0.35um CMOS cascode low noise amplifier using an active inductor. The inductance required to output of cascode pair is synthesized by an active inductor in Compact Wu Folded configuration. The LNA presents a gain of 12.04 dB with a noise figure of 4.78 dB at 1.8 GHz. The layout is presented occupying an active area of 0.165 mm2. The results are satisfactory, validating a compact design and demonstrating the technical feasibility of this topology in the band of interest.