Stand-alone buoys are used as navigation aids and for scientific marine research, including the measurement of seismographic movements of the seabed as part of a tsunami warning system. Solar power is commonly used to power up the electronic devices of these buoys. However, due to limitations in delivering constant power from solar panels, linear electric generators have been employed as an alternative/additional power source to convert the energy of oceanic waves into electricity.The variable AC amplitude and frequency of the generated voltage waveform is usually converted to DC using a simple, low cost diode bridge rectifier resulting in a low operating power factor (PF) and low power transfer capacity because of the high inductive reactance of linear electric generators. A Forced Commutation Controlled Series Capacitor (FCSC) technique is employed in this paper to improve the PF of these variable amplitude and very low and variable frequency devices. FCSC circuits have been employed in the past in power transmission networks where the voltage and frequency are fixed, but never in a wave power application where the amplitude and frequency of the AC voltage are variable.This paper provides an analytical description of the proposed FCSC converter. The method is experimentally demonstrated and evaluated using a 2.25kVA test circuit. A comparison of the performance of the FSCS circuit with a standard uncontrolled single-phase diode bridge rectifier circuit is included.

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This paper compares controlled series capacitor (CSC) converters applied to generator-sets used in series hybrid electric vehicles (SHEV). The operation of each circuit is discussed and simulated using Matlab/Simulink. It is concluded that CSC converters can improve the power factor (PF) of the generator-set.

This paper compares by simulation the Thyristor Switched Series Capacitors (TSSC) Circuit with the Thyristor Switched Parallel Capacitors (TSPC) Circuit for wind turbines. The well-known TSSC circuit belongs to the Controlled Series Capacitor (CSC) circuits that have been used in power transmission lines in order to correct the power factor and improve the performance of the electrical system. Such a circuit can be used in wind power systems to improve and maximize the efficiency of a wind turbine. A typical direct-drive wind power system employs variable speed electric generators, but the downside is that systems like that suffer from high inductive reactance. A TSSC circuit, therefore, is able to counteract for any reactive losses, and improve the power factor as well as the efficiency. The main issue with the TSSC circuit is the use of a high number of capacitors that must be connected in series, which can increase the cost and the maintenance of the controller. This paper introduces a novel circuit with different control technique than the TSSC that employs capacitors in parallel configuration. The novel TSPC circuit was simulated in PSPICE and the benefits as well as the drawbacks are described

This paper presents a novel power factor correction circuit suitable for low-speed electric generators usually used in direct drive wind turbines. The Thyristor Switched Parallel Capacitors (TSPC) circuit belongs to the Controlled Series Capacitor (CSC) circuits. Those circuits have been used in power transmission lines to correct the power factor and improve the performance of the electrical system. Such a circuit can be used in wind power systems to improve and maximize the efficiency of a wind turbine. A typical direct-drive wind power system employs variable speed electric generators, but the downside is that systems like that suffer from high and variable inductive reactance. In order to correct the power factor and to improve the efficiency of the system, the inductive reactance of the generator must become equal in value to the capacitive reactance. A TSPC circuit uses a set of capacitors, connected in series with anti-parallel thyristors. In every cycle, a controller triggers the appropriate thyristors, allowing the current to pass from the capacitor which then provides the system with the capacitive reactance that matches the generator’s inductor reactance. Therefore, the TSPC circuit is able to counteract for any reactive losses and improve the power factor, as well as, the efficiency. This paper introduces this novel power factor correction circuit that employs capacitors in parallel configuration. This circuit was simulated in PSPICE and was implemented and tested in the lab. Based on the simulation and implementation results, we discuss the benefits as well as the drawbacks of the proposed circuit