Photovoltaic Based Stabilising The Load Distribution Feeders Using Lpc

Fig.3. shows algorithm for the proposed method. This algorithm uses voltage and current of the PV module. A permitted error of 0.06 as shown in (8) is used in modified algorithm to eliminate the steady state oscillation in the system. The permitted error is written as  I + V dI/dV   0.06 Using the permitted error of 0.06, the steady state error is approximately 0.7% based on the duty cycle step size of 0.005.

Fig. 9(a) shows the DC-link voltage across the DC-link capacitor of the PV array. The DC-link reference voltage corresponds to maximum power point of the PV array. Fig. 9(b) shows the power demand by the load, and power flows from the grid and PV system generated power. As the PV system generated power could not meet complete power demand of load, remainining power is supplied by the grid. At 1secocond the PV system switched from partially shaded condition to uniform solar insolation. Thus, at this point power supplied by the inverter and grid also varies. Fig. 10(a) shows the grid current which is fully sinusoidal. Fig. 10(b) shows the inverter output current. Fig. 11 shows the performance of system under reactive load condition. In this study, a 500VA reactive load is considered. The figure shows the complete reactive power is supplied by the inverter. Thus the power factor of the system is maintained nearly at

The parameters of this controller (PI- 1) can be decreased during the voltage sag in order to improve the performance of the proposed method.

The statistical table of photovoltaic power generation in Golmud area was reported by the power company of Qinghai province in March, 2012: there are several photovoltaic power station generating capacity was even zero in the first two months. Apparently, systems of parts of stations had the design problems, such as no stability control device; lack of power forecasting or signal impassability; the insulation does not meet the requirements.

In recent years, Energy comes from natural resources such as sunlight, wind, rain, tides and geothermal heat. These resources are renewable. Therefore, for all practical purposes, these resources can be considered to be unlimited, unlike dwindling conventional fossil fuels. The renewable energy sources are known to be much cleaner and produce energy without the harmful effects of pollution unlike their conventional counterparts. Solar energy is converted into electrical energy and the electrical power generation in PV systems is highly affected by the temperature and the insolation level which makes it impractical to directly connect them to the load without any storage devices or utility grid interface. The PV systems focused on the minimization of the installation costs and the maximization of the energy capture and conversion efficiency. In order to maximize the conversion efficiency, the PV system should be operated at its maximum power point (MPP). This power is supplied to the load using parallel power processing topology to reduce the amount of power processed through the converter and, hence, decrease the converter size and increase the efficiency by means of direct energy transfer (DET).The concept of the PPP topology is shown in Figure.

abstract: Current scenario of the globe is that sources for energy are lagging behind the current demand so most concentration is on renewables. Solar performance efficiency mainly depends on cell structure, maximum power point tracking technique and converter circuit used. MPPT operation executes a key part in raising the strength of PV system. A p & o, incremental conductance, Fuzzy based MPPT algorithmic principle is anticipated with a boost converter. Two in and single out Mamdani’s fuzzy framework with triangular membership is used to concoct the controlled current. The anticipated procedure is upheld in MALAB/SIMULINK and in this way the maximum power point tracking performance is evaluated. The anticipated system tracks the most in operation reason with no wavering and enhanced exactness. The reproduction results demonstrate the adequacy of the anticipated method.

This paper proposes a new real and reactive power coordination controller for a unified power flow controller (UPFC). The basic control for the UPFC is such that the series converter of the UPFC controls the transmission line near the micro grid real/reactive power flow and the shunt converter of the UPFC controls the UPFC bus voltage/shunt reactive power and the DC link capacitor voltage. In steady state, the real power demand of the series converter is supplied by the shunt converter of the UPFC. To avoid instability/loss of DC link capacitor voltage during transient conditions, a new real power coordination controller has been designed. A new PSO based reactive power coordination controller has been designed to limit excessive voltage excursions during reactive power transfers. Matlab simulation results have been presented to show the improvement in the performance of the UPFC control with the proposed real power and reactive

Current scenario of the globe is that sources for energy are lagging behind the current demand so most concentration is on renewables. Solar performance efficiency mainly depends on cell structure, maximum power point tracking technique and converter circuit used. MPPT operation executes a key part in raising the strength of PV system. A p & o, incremental conductance, Fuzzy based MPPT algorithmic principle is anticipated with a boost converter. Two in and single out Mamdani’s fuzzy framework with triangular membership is used to concoct the controlled current. The anticipated procedure is upheld in MALAB/SIMULINK and in this way the maximum power point tracking performance is evaluated. The anticipated system tracks the most in operation reason with no wavering and enhanced exactness. The reproduction results demonstrate the adequacy of the anticipated method.

The growing concern about the impact of CO2 and the anxiety on the effect of using fossil fuels based power generation technology on the environment, in recent years, has made the researchers to focusing on the renewable energy based clean power generation techniques to secure the environment from carbon effect. Among the development of renewable energy based power generation techniques, the solar power generation has a major role in clean power generation. The sunlight is free of cost and everlasting energy sources, but the drawback of this method is that generation of electricity is only possible during the sunshine. In PV system, the DC-DC power converters are used to change the output voltage from one level to another level [25-27]. Typically, the DC-DC converter is connected between the panel and the load, sequentially to extract the available power from the panel using tracking methods. In this work, Boost converters and Super lift boost converters [1] are used to extract the maximum power from the panel and two converters diagram is shown in Figure 1a and Figure 1b respectively.

In the industrial sector the various motoring loads are continuously running and generating the inductive load. So the power factor in this system gets reduced due to the inductive reactive power. But the electricity board has a standard limits regarding the power factor values and if the power factor goes below the specified limit; the electricity company charges the penalty to the industrial consumers. The automatic power factor correction panel provides the required compensation to overcome the inductive reactance by using the power capacitors. The microcontroller PIC receives current signal from current transformer and simultaneously gives the signals to the various contactors to connect the capacitors in the line for the compensation. Thus by adding the capacitor to the line will compensate the reactive power and maintains the power factor near to unity. This will avoids the penalty to the industrial consumers and may get the incentives. In the conventional methods we were using the fixed capacitor for compensation. But these were leading to excessive charging of the capacitors causes the voltage surges. Thus it becomes difficult to main power factor near unity by on and off operation of fixed capacitor. The contactor switched capacitors are connected and disconnected automatically eliminating the previous problem.

Nowadays, renewable energy resources play an important role in replacing conventional fossil fuel energy resources. Photovoltaic energy is one of the very promising renewable energy resources which grew rapidly in the past few years. Photovoltaics has one major problem and which is that with the variation of the operating conditions of the array, the voltage at which maximum power can be obtained from it also changes. In the thesis, a PV model is used to simulate actual PV arrays behavior, and then a Maximum Power Point tracking method and wind energy system using Feed Forward Neural networks is proposed in order to control the power. Further more,the proposed feed forward neural network technique using hybrid system is compared with the ANFIS(adaptive neuro fuzzy interference system). Simulation results shows that the proposed feed forward neural network maximum power point tracking method gives faster response than the ANFIS

In the traditional distribution network, the systems are designed and controlled autonomously. Hence a fault at a system will have serious problem and need immediate rectification. But, rectification of these problems is very difficult. More due to the increase in prices of fossil fuel which are the main cause for generating electricity. Thus, centralized control and integrating their functions is a crucial problem faced in the traditional distribution network. To overcome these issues, there comes Information and communication Technology (ICT) to integrate all the important elements in a distribution system. This develops an environment at distribution level, which is controlled and integrated called “smart grid” which bring up to the date where the electricity generated is transported, distributed by optimizing the system’s economy and the improving the system’s capability to spring back into shape.

This high number of renewable energy penetration especially in LV network has raised new way of utilizing bidirectional power flow in the distribution network. Bidirectional power flow from DG, is common phenomena now a day’s .For example, in a normal sunny day, the average PV generation would be high compared to cloudy day; and, the load requirement during day time in residential areas are quite low compared to early evening to night time. As, PV installations are carried out keeping the total load demand from a house , during the sunny day, the PV can easily exceed the load demand and generate excess power than required. This power is then back flowed to the distribution network causing bidirectional power flow. From recent trends, in most of the countries with PV installation in the world, this bidirectional power flow is allowed in the grid via the smart meter and the distribution retailers pay the consumer for supplying power to

Feed forward control is a reliable for rejecting fast and dynamic voltage disturbances in the phase grid. Mainly in this scheme implemented in phase voltages of the Wyes connected configuration. Under this unbalanced and distorted grid conditions, the online conversion of line - to - line values into the phase value is unworkable. In order to an exploit full advantages of feed forward controller is a most appropriate modulator is needed. In this article the feed forward of grid line-to-line voltages is used in phase voltages. The introduced feed forward method is implemented in Implicit Zero Sequence Discontinuous Pulse Width Modulation (IZDPWM) technique that is compatible for grid connected inverters. Regarding in the IZDPWM grid topologies distorted the harmonics of the grid voltages. Hence, a sinusoidal current is injected to the grid. Moreover, the measuring grid line-to-line voltages two sensors are required; hence an overall system costs is reduced and control system reliability is increased. The time-domain simulations in MATLAB/Simulink and experimental results from a Hardware based laboratory prototypes are in good agreements,

The control of active power and frequency in a power system is referred to as load frequency control (LFC). Stable operation of interconnected power system requires both constant frequency and constant tile-line power exchange [1]. An area control error (ACE), defined as a linear combination of tie line power and frequency deviations, is taken as the controlled output of LFC. LFC regulates ACE to zero such that frequency and tie-line power errors are forced to zeros. PID controller is widely used in LFC due to its simplicity but is gives long settling time and produces large frequency deviation [2]. In recent years, active disturbance rejection control (ADRC) developed by J. Han [3] and modified by Z. Gao [4, 5] has been proposed for the LFC controller [6-9].