Kazuto Yukita

Notice of Retraction Research of PV Model and MPPT Methods in Matlab

The power generated by the PV generator depends on the irradiance, temperature, and surface conditions. The PV generator has a nonlinear characteristic, and the power has a maximum power point or multi-local maximum power points under different conditions. Various MPPT methods have been reported, in order to confirm the effectiveness of each control method, experimental or simulation analysis is used, from economical point of view, simulation analysis is more effective. In this paper, a versatile, accurate Matlab/Simulink PV model suitable for use by power electronics specialists has been developed, and has been designed for easy implementation on Matlab/Simulink platform; conventional MPPT methods and MPPT methods suitable for partial shading conditions can be simulated by using this PV model.

A study of electric power quality using storage system in distributed generation

This paper describes a method to improve the power quality of a distributed generation (DG) power system. The proposed method uses a power storage system with DG. Here, DG is assumed the renewable energy systems such as photovoltaic generation (PV), wind power generation (WG) and fuel cells (FC), etc. The effect to use the storage battery is shown by the following two experiments. One case is the examination of a power transmission simulator. Another case is an experiment in a small-scale actual system. The electric power quality (frequency, voltage) is observed, when the storage battery have been introduced or not. In case of a power transmission simulator, the frequency control is executed using two methods; a power demand estimation method and a proportion control method that uses frequency deviation. The control of the storage battery is executed by using these controls. Another case is an examination for a real power system, which is the 12th pavilion of Aichi Institute of Technology (AIT). In this pavilion, photovoltaic generation (PV), wind power generation (WG) and storage batteries have been introduced. And the electric power is supplied by these sources. The electric power qualities in two cases were compared. One case is the storage battery is introduced. Another case is without the storage battery. The storage battery executes the control that maintains the voltage in the power system. As a result, it has been understood that the electric power quality has improved, when the storage battery is introduced.

Study of load frequency control using fuzzy theory by combined cycle power plant

This paper proposes a new control method using the combined cycle power plant that consists of multi-power generation units, to improve the load frequency control (LFC) characteristics and to secure the regulation capacity in power systems. The proposed method, first, uses a TBC-type output set-point control based on a power demand estimation method. Next, to improve stability and robustness in this system, the fuzzy control using the phase plane is implemented. Then, the number of units in combined cycle power plant with LFC is determined by the fuzzy theory using the rule table. The effectiveness of study, for the proposed method, is examined with the two-area LFC system which is composed of a combined cycle power plant that consists-of seven units and a steam power plant considering the boiler system, as a model system for the computer simulation.

Study of load frequency control for a microgrid

This paper describes a method to enhance the load frequency control in a power system with distributed generations (DG). In this paper, a power storage system is used with solar photovoltaic generations and wind power generations. The microgrid system at Aichi Institute Technology in Japan is used as a simulation model. For each simulation, which was carried out by using a power transmission simulator, the model of the microgrid included one DG and a storage system. The effectiveness of load frequency control using the storage system was examined. It was confirmed that the electric power quality improves when load frequency control is carried out with the storage system.

Study of AC/DC power supply system with DGs using parallel processing method

This paper proposes a new AC/DC power supply system with DGs using the parallel processing method. The purpose of this system is to supply the power without connecting to the utility gird. The DGs consist of photovoltaic (PV) and wind generators (WG), and the main energy source of this system is the DGs and the UPS battery. When the system does not get enough energy from the DGs, and the power supply of the battery runs out, this system connects to the utility grid and begins to charge the battery and supply to the load. In this study, we focused on the AC power supply and DC power supply from DGs. Then, the converter of DGs uses two kinds of DC/DC type and DC/AC type. Also, the load uses two kinds of DC load and AC load. The proposed the power system has been operated with the actual loads of 20 kW in the campus of the Aichi Institute of Technology.

Load frequency control using storage system for a micro grid

This paper describes a method to enhance the load frequency control in a power system with distributed generations (DG). In this paper, a power storage system is used with photovoltaic generation and wind power generation. The microgrid system at Aichi Institute of Technology in Japan is used as a simulation model. For each simulation, which was carried out by using a power transmission simulator, the model of the microgrid included one DG and a storage system. The effectiveness of load frequency control using the storage system was examined. It was confirmed that the electric power quality improves when load frequency control is carried out with the storage system.

Automatic generation control using GA considering distributed generation

This paper examined the automatic generation control method in the power system that introduced distributed generator. Examined content is the case of they distributed generator participated/nonparticipated in the frequency control of the system. Control of the power plant in each area is the case of the control method using the load demand estimation and fuzzy control using GA. To study the effectiveness of the distributed generator, this paper considered the computer simulation 3-area automatic generation control model system which introduced the distributed generator.

A study on power system transient stability due to introduction of superconducting fault current limiters

This paper describes the experimental results by using the power transmission simulators and the computer simulation using EMTDC, about the superconducting fault current limiters (SCFCL) on improvement of power system stability and suppressing fault currents. The experiments and the simulations in this paper were carried out using the R-type and L-type SCFCL. The R-type SCFCL is simulated by using a resistor and an electromagnetic contactor with thyristors. The L-type SCFCL is simulated by using a reactor and an electromagnetic contactor with thyristors. It is found that the SCFCL in the electric power system gives the improvement of the suppressing fault current and power system transient stabilities.

Power supply system of DC/AC micro grid system

This paper proposes an AC/DC power supply system with DGs using the parallel processing method. The purpose of this system is to supply the power without connecting to the utility gird. The DGs consist of photovoltaic (PV), -and wind generators (WG), and the main energy source of this system is the DGs and the UPS battery. When the system does not get enough energy from the DGs, and the power supply of the battery runs out, this system connects to the utility grid and begins to charge the battery and supply to the load. In this study, we focused on the AC power supply and DC power supply from DGs. Then, the converters of DGs use two types, DC/AC type and DC/DC type. The power supply system has been operated with the actual loads of 20 kW in the campus of the Aichi Institute of Technology. This paper reports on our study of DC and AC power supplies in the event of a system anomaly.

A Pole Change Generator for Micro Windmill with Maximum Power Point Tracking System

This paper proposes the pole change generator for micro windmill with maximum power point tracking (MPPT) system. First, to show the effect of the pole change generator, the generator and the pole changing controller are made. Then, the pole change generator can make the values of best load by converting the pole number. Next, the input variable and the control method are examined for the improvement in a control performance of MPPT control. Then, the MPPT is the climbing a mountain method. The proposed method was able to maintain the output of power generation for a wide load change. The proposed method is a good control characteristic.