Ontoseno Penangsang

Modeling and simulation of MPPT-bidirectional using adaptive neuro fuzzy inference system (ANFIS) in distributed energy generation system

Photovoltaic system (PV) is widely used in various renewable energy application. The main problem of PV system is how to get the maximum output power. Furthermore, the redundancy output power generated by on a distribution system should also be considered. This study utilizes the excess power for energy storage using bidirectional converter. Since the DC voltage which generated by PV and the energy storage will be converted into AC voltage using inverter toward load. This paper proposes ANFIS as search optimization method using SEPIC converter with a maximum efficiency of 99.95%.

Smart-Meter based on current transient signal signature and constructive backpropagation method

Increasing of electric power consumption and electricity price are making customers more sensitive in addressing the issues. Therefore, the accuracy of the recording device power consumption (kWh-meter) becomes an absolute necessity to reduce potential conflicts that may arise. This paper proposed prototype of smart-meter which combines transient peak value and steady state values to identify an activity of electrical appliances. These values are used as the identity of electrical appliances that will be taught to Constructive Backpropagation Neural Network (CBP-NN) to record power consumption in detail, including type appliance and time use. The proposed method has very simple structure, it only uses two input (transient peak value and steady state values) and single hidden layer with five neuron. The number of output is equal to the number of appliance. So that, the proposed method implement in microsprocessor system or in standalone product. Simulation and experimental results have validated the performance of the proposed method to operate in a real system.

Security constrained optimal power flow with FACTS devices using bender decomposition

This paper deals with security constraied optimal power flow (SCOPF) in which FACTS devices are employed to meet system constraints under both normal and contingency states. The considered constraints are power generation limit, voltage limit, transmision limit and FACTS devices operation limit. In normal state, the objective function is to minimize operation cost while satisfying system constraints. If contingency occurs, FACTS devices are optimally controlled to eliminate violation of generator ramp rate as well as to meet system constraints. The iterative process is applied to ensure that there will be no generator ramp rate violation. Initially, normal state is simulated to obtain optimal power dispatch as a basecase. Using this basecase, contingency state is simulated in order to minimize generation ramp rate violation. If ramp rate violation is failed to be eliminated, the violation will be fed back to normal state as a basis to re-arrange the output of generators that will be the next basecase. By this basecase, contingency state is again simulated. This iterative process involving normal and contingency states will stop if ramp rate violation is no longer exist. To decompose main problem into normal and contingency state, Bender decomposition technique is used with relation between power generation under normal and contingency states as a coupling equation. The power generation deviation of particular unit should be less than the corresponding generator ramp rate. Each optimization problem is solved by sequential quadratic programming (SQP). IEEE 14 bus will be used to show the ability of the proposed approach to solve the SCOPF.

Dynamic DC optimal power flow using quadratic programming

This paper proposes a quadratic programming for solving the dynamic direct current optimal power flow (DDCOPF). The DDCOPF solves OPF with multi load levels in which ramp rate of committed units become coupling between two series load levels. To overcome this problem, a very large matrix may be required. The more number of load levels are considered, the larger matrix will be used. Consequently, it may take long computation time to solve. Therefore, the DC load flow is preferable than AC load flow. To show the effectiveness of the proposed approach, IEEE 14 bus test system is used. In addition, application of the proposed approach to real system Jawa Bali 500 kV 25-bus is presented.

Dynamic optimal power flow with geothermal power plant under take or pay energy contract

This paper deals with dynamic optimal power flow (DOPF) considering geothermal power plant under take or pay (TOP) contract. As located in ring of fire, Indonesia has high potential of geothermal resources. Therefore, geothermal power plant becomes promising solution of power shortage in Indonesia. However, it takes high investment cost to develop geothermal power plant. In order to attract the investors to spend their money in developing geothermal power plant, the Indonesian government applies take or pay scheme in buying electric power from geothermal unit. This scheme is aimed to ensure cost recovery of the unit. When applying take or pay scheme, system operator may use DOPF formulation to make daily operation planning. The DOPF problem is solved using Matlab-based quadratic programming (QP). Then, IEEE 30 bus system is employed as tested system to show the effectiveness of the proposed approach.

Quadratic programming approach for security constrained optimal power flow

This paper proposes an approach for optimal power flow considering several contingency states. Initially, contingency selection is conducted to measure how much a specific contingency may affect the operation cost. Then, some severe contingencies are incorporated into optimal power flow problem. All considered states, normal and contingency states, are simulated simultaneously. Thus, if contingency occurs, it can be ensured that all constraints such as generation limit, transmission limit and ramp rate will be satisfied. To solve the problem, quadratic programming is applied. IEEE 30 bus system is used as test system to show the ability of the proposed approach.

Capacitor Placement and Sizing in Distorted Distribution Systems Using Simplified Direct Search Algorithm

 Abstract—In distribution systems, shunt capacitors are added in order to reduce the total active power loss and improve the power factor. However, the installation of shunt capacitors in distorted distribution systems will amplify the harmonics distortion level, if it is not placed in a proper location with harmonics consideration. Therefore, to take into account the presence of harmonic distortion, this paper proposes a simplified direct search algorithm to determine capacitors placement and sizing in distorted distribution systems. This algorithm is connected to harmonic power flow to search the proper location and size of shunt capacitors, which can decrease the total active power loss and increase the power factor, while the total harmonic distortion does not exceed the maximum allowable harmonic distortion level at each bus. To validate the method proposed, this algorithm is tested on 13-bus radial distribution system and 34-bus radial distribution system with harmonic current injection in order of 5, 7, 11, 13, and 17.

Security constrained optimal power flow incorporating preventive and corrective control

This paper proposes an approach for optimal power flow with incorporation of preventive and corrective control. The approach is useful for operation planning to guarantee secure operation under both normal and contingency states. Therefore, the approach consists of main problem and sub problem representing normal and contingency states, respectively. In normal state, preventive control is used to secure the system while in contingency state, corrective control is employed to satisfy system constraints. The objective of main problem is to minimize operation cost while the sub problem is aimed to minimize power generation deviation in order to avoid ramp rate violation. The approach uses iterative process involving normal and contingency states. At contingency state, power redispatch is conducted as corrective control to avoid system violation. If power redispatch violates ramp rate of generator unit, the exceeding power will be fed back to normal state to recalculate the generator output in the normal state. This calculation in normal state is called as preventive control. To show the effectiveness of the proposed approach, IEEE 9 bus system and modified Jawa Bali 25 Bus system is used. The result shows that the proposed approach is able to secure the operation under both normal and contingency states.

Optimal Design of TCPST Using Gravitational Search Algorithm

This paper presents the GSA method is used to determine the optimal locations and ratings of TCPST. TCPST is the equipment used to regulate and improve the power flow on the power system. TCPST is implemented on the Java-Bali 500kV power system. The objective function of this study is to minimize the active power losses on transmission line of Java-Bali 500kV power system. The active power losses on transmission line of the Java-Bali 500kV power system before optimization using Newton Raphson method is 297.607MW. While the active power losses results after optimization using the GSA method with 4-TCPST is 234.885MW.

Simultaneously placement and sizing of multiple DGs and shunt capacitor banks in unbalanced distribution systems using real coded GA

The allocation of local active and reactive power in distribution systems is very important to meet customer demand and maintain the quality of electrical energy. Power loss and voltage deviation can be minimized by placing Distributed Generations (DGs) or Shunt Capacitor Banks (SCBs) in the right places and with the appropriate size. This paper discusses simultaneously placement and sizing of multiple DGs and SCBs in unbalanced distribution systems for power loss and voltage deviation reduction while maintaining harmonics at the IEEE-519 standard limit. Real Coded Genetic Algorithm (RCGA) is employed to determine the location and size of SCBs and DGs. The proposed method is applied on Modified Kaliasin radial distribution systems. The results show that the placement of the DGs on the bus 7, 8, 9, 10 is the most powerful results in reducing losses and voltage deviation compared to the other scheme. Placement 4 DGs with the size of each is 135 kW reduce the active power losses of 35.80% and the reactive power of 35.81%. The minimum bus voltage before and after placement DGs are 19.906 kV and 19.928 kV respectively.