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The converter transformers are reported to fail generally on the thyristor-valve side, where complex alternating voltage waveforms superimposed with dc voltages would occur. The effect of these waveforms on the failure and endurance of the valve side winding insulation of the transformers is not yet understood, which is investigated here. In this paper, the voltage waveforms occurring in a converter transformer are obtained through PSCAD/EMTDC for a typical double pole ±500 kV, 1000 MW DC-link HVDC transmission system based on the CIGRE benchmark system. The waveforms are then amplified using a High Voltage amplifier for experimental breakdown investigations. Stepped-stress damage equalization method has been used for obtaining the lifetime characteristics from failure data. A comparison with life curve under pure sinusoidal and actual alternating voltages with superimposed dc and harmonic voltage has been made to understand why the converter transformers generally failed on the valve side. The results first time give fundamental reasons for the possible failure of the converter transformers and put forth important design considerations.

This paper presents a modified Damage Equalization Method with statistical features for life estimation of dielectrics. The paper postulates damage as a random variable, which resulted in establishing a relationship between the Weibull scale, shape parameters and the endurance coefficient ‘n’ of inverse power law. By the modified DEM (m-DEM), for the first time, a range of values of $n$ for each material is proposed, which is useful for design engineers. Until now, the endurance coefficient of inverse power law and strength constant were treated as constants. Here, it is shown that these coefficients do have statistical features or variations. Experiments are conducted on oil impregnated paper and LDPE samples using accelerated step-stresses for life estimation. The results of the estimation of endurance coefficient are compared with existing methods and reasonable conclusions are drawn in favor of the proposed method.

In this paper, electric field and space charge accumulation have been investigated for needle-plane system (defect) under DC voltage conditions. Prolate spheroidal electrode system, believed to be closer to needle-plane system, has been used for solving the governing differential equations, numerically, for space charge and electric field distributions. Unlike past works in which space charge at needle tip was assumed either qualitatively or quantitatively, in this work, space charge formation is estimated using nonlinearity of material properties alone. A comparison with previous methods based on concentric spherical electrode approximations reveals that the results are different for prolate spheroidal system at different nonlinearities. Interesting results on the role of nonlinear conductivity on the DC electric field and space charge accumulation at needle-tip are presented. Furthermore, needle tip-plane breakdown experiments are conducted and the results suggest a reasonable and realistic estimate of tip-field at breakdown, using the proposed model.

In this paper, carefully designed experiments are reported, which indicate that the change in frequency of voltage polarity reversals results in a change in slope of v-t characteristics on the inverse power law. The power law parameters are shown to be systematic functions of frequency of polarity reversals. Based on these results, the authors propose a comprehensive inverse power law for DC polarity reversal stress application, in place of conventional inverse power law. The proposed modification is examined with experimental data of authors apart from that available in literature and found to be working well. The model provides the maximum frequency of a reversal for maximizing the life of power equipment which may pave the way for deciding on the maximum frequency of voltage reversals.

In this paper, the electric field, space charge and temperature distributions across a double layered dielectric are investigated under DC voltage. The dissimilarity of material properties of different layers, the effect of electric field and temperature dependent conductivity are found to play critical role in the electro-thermal problem of multi-dielectrics. At the interface, Maxwell-Wagner polarization is incorporated for electric field and interfacial charge, while temperature is considered as a continuous function of space inside the material. The current continuity equation, thermal continuity equation and Poisson's equation are simultaneously solved using numerical methods in parallel-plane electrode geometry. The electric field distribution, temperature distribution, space charge distribution and thermal breakdown limits are obtained at various boundary temperatures for different thickness proportions of layers.

Surface voltage measurement of an insulated overhead conductor assumes importance for understanding corona, radio interference voltage and for design purposes. Surface voltage measurement of a bare overhead conductor is quite simple as a voltage divider can be directly connected. However, there are challenges in the measurement of surface voltage on an insulating surface of an insulated covered conductor using voltage dividers. In case of ac measurements, the capacitance parameter dominates in deciding the potential distribution. In this article, it is demonstrated that the measuring system itself will alter the voltage division between the capacitance of the cylindrical insulated conductor and that of surrounding air acting as a capacitive divider. The voltage distribution is shown to be drastically influenced by the measuring system capacitance. In view of these issues, a novel experimental method is proposed for the measurement of surface voltage of an overhead insulated covered conductor. In general, the method can be applied to any cylindrical insulated conductor and for calibration of sensor-based measurements. The proposed empirical method is tested by a validated simulation of the entire system and it is proven analytically. The radial voltage gradients are then estimated from measured surface voltages. The analytical, experimental, and simulation results are in close conformity.

Energy consumption is a vital aspect for any industry considering the cost-effective aspect. The current study embodies the power consumption during filtration of conductive filters at different dust pre-charging levels on laboratory-based pulse jet tubular set up assisted with pre-charger. Three types of polyester conductive non-woven filter materials, viz. PTFE-coated media, stainless steel fibre blended with PET media and stainless steel scrim media, have been characterized at three different charge levels, viz. 4 kV, 8 kV, 12 kV, and without charge. The outcome revealed that there has been a significant drop in power consumption with the rise in pre-charge level. Energy utilization results have further been compared with full-scale bag house condition by calculating the energy consumed for 50 bags. The results showed that among all the materials taken for investigation the performance of PTFE-coated media is the best and role of material is most significant towards the energy consumption by the filtration system. Overall energy consumption decreases with rise in pre-charging level. It is observed that percentage contribution of energy utilized for fan has been much higher for full-scale bag house as compared to tubular-based set-up. However, in case of energy consumed by the compressor, the difference in percentage contribution is relatively less and for energy utilized due to charge, not much variation in contribution can be noted.

Homocharge, particularly, positive charge near anode has been observed inside low-density polyethylene (LDPE) by many researchers. However, the phenomenon is yet to be understood theoretically and mathematical analysis is pending, although, simulations have been reported. Simulation of evolution of space charge in LDPE, with time and space, using bipolar charge transport model considered only drift component of charge carriers inside the dielectric. The experimental results suggest significant concentration gradient in space charge distribution. The authors derived a comprehensive drift and diffusion based analytical models, for the time/space evolution of space charge and electric field in dielectrics using Maxwell's equations, current continuity equation, conduction and injection mechanisms. The proposed analytic models of electric field and space charge distribution entwines charge injection at electrodes and charge transport inside the medium, which seem to have not been reported until now. Remarkable, believed to be unprecedented, agreement between the analytical and experimental results has been observed. Using the model, the role of conduction, injection, diffusion on homocharge accumulation has been investigated. Pulsed electroacoustic method is used for the measurements of the space charge dynamics.

The current investigation demonstrates the filtration behaviour of two non-woven polyester conductive filter media, viz. stainless steel (S.S.) fibre in the scrim of PET filter media and carbon filament in the scrim of PET filter media. Both the materials are characterized at different charge levels, viz. 0 kV, 4 kV, 8 kV and 12 kV, respectively, at a particular face velocity (m/min) and inlet dust concentration (50 g/m3) on laboratory-based pulse jet filtration test rig set-up. The tests were conducted at ISO-11057 filtration standard, and the data collected are for 2 h of final measuring phase. Outlet emission in terms of PM2.5, PM10, mass concentration, particle number concentration, collection efficiency and also residual pressure drop is found to be considerably lower for S.S. fibre in the scrim as compared to carbon filament in the scrim. With an increase in dust charge level from 0 kV to 12 kV, the downstream emission and residual pressure drop show a decreasing trend for both filter media. The particle size distribution, i.e. D10, D50 and D90 values, is higher at increased charge. On the basis of all the interpretations, the filtration behaviour of S.S. fibre in the scrim of PET filter media is found to be better.

Energy consumption is an important aspect for any industry which directly relates to its profit margin. In the present study energy consumption during filtration of conductive filters has been analyzed at different dust charge levels on laboratory-based pulse jet system assisted with pre-charger. Five types of polyester conductive material viz. PTFE coated media, Stainless Steel Fibre blended with PET media, Stainless Steel Scrim media, Carbon Fibre blended with PET media and Carbon Filament Scrim Media have been characterized at three different charge levels viz. 4, 8, and 12 kV, and without charge. The results showed that there is a significant drop in consumption of energy with the increase in pre-charging. Energy consumption results were further compared with full scale bag house condition by calculating the power utilized for 100 bags. The outcome revealed that among all the materials the performance of PTFE coated media is the best and role of material is most significant toward the energy consumption by the filtration system. Overall energy consumption is reduced with the increase in charge level in the pre-charger. It has also been noted that percentage contribution of energy consumption for fan energy is much higher for full scale bag house as compared to flat media test rig. While for compressor energy, the difference in percentage contribution is comparatively less and for energy due to charge, there is not much variation in percentage contribution.

In this paper, a novel trapezoidal multi-coil antenna is proposed to mitigate lateral misalignment in wireless charging application of electric vehicles (EVs). The proposed coil antenna used at the transmitter is optimized to improve stability of induced voltage which intern is expected to provide a stable power transfer efficiency over a wide range of vehicle’s misalignment. The proposed design adopts an isosceles trapezoid shape after analytical optimization and consists of three series connected coils placed at the top faces of the structure. The magnetic field distribution originated from this complex geometry is analytically modeled and optimized to obtain wider uniformity in the induced voltage of the receiver coil as compared to a conventional planar antenna. The design is verified using commercial EM software and results are corroborated. The results show that the proposed antenna provides enhanced tolerance towards misalignment is proved to be a potential design for wireless powering application of EVs.

In this paper, a smart hybrid Fast Goertzel Algorithm and RLS-Adaptive Filter based control scheme for harmonic elimination, load balancing is presented. The control algorithm is designed for shunt active power filter (SAPF) connected in parallel with grid under distorted load conditions and non-linear load. The function of the fast Goertzel algorithm is to extract the fundamental frequency component with its magnitude and phase from the load currents. This extracted fundamental frequency component is used for estimating the reference currents based on the Recursive Least Squares (RLS) adaptive filter approach. This hybrid FG-RLS (Fast Goertzel-Recursive Least Square) control algorithm retains its behaviour even under load unbalancing and sudden load shutdown. Such improvement helps the adaptive filter for better convergence rate with less computation burden. The performance of the proposed FG-RLS scheme is simulated on three-phase applications to demonstrate its capability for extracting the fundamental component and further estimating reference currents.

In high voltage insulation system, the insulation will be undergoing various stresses and the life of the insulation will be different from uniform fields when stressed by a divergent field. In this paper, dc breakdown experiments at different step stresses are conducted using needle-plane and plane-plane electrode systems. Using the data from the breakdown tests, assessment of life of the insulating material can be done by estimating the voltage endurance coefficient (n) and accumulated damage. Stepped-stress damage equalization method (SSDEM) is used for estimating the life of the insulating material used. Interesting results on the role of uniform and non-uniform field on endurance coefficient is reported which in turn shows the effect of divergent and uniform stress on the life of the insulation. Furthermore, in this study, a numerical model is developed to estimate the electric field around the tip of the needle electrode using a semi-empirical equation of nonlinear conduction under steady state DC. Spherical geometry system is used for solving the differential equations numerically. The results show the developed numerical model can predict the Poisson's field when conduction is field dependent.

The present study embodies the response of two different filter media viz. conductive filter media (stainless steel blended with PET fibers) and PTFE-Coated polyester filter media, at four different charge levels (0 kV, 4 kV, 8 kV, and 12 kV) and at a particular dust concentration (50 g/m3) on pulse-jet filtration process performance. The filter media were tested at ISO-11057 standard with conducting 200 pulsing cycles at final measuring phase. Emission values in terms of PM2.5 and PM10 mass concentration and number particle concentration were comparatively lower while using PTFE-coated filter media in comparison with conductive filter media. Downstream emission values largely reduced for both filter media, particularly at high charge level. PTFE-coated filter media exhibit lower residual pressure drop as compared to conductive filter media when measuring the phase of filtration operation, whereas on the contrary D10, D50, and D90 values were found higher for PTFE-coated filter media and higher charge level. Overall, it can be summarized that PTFE-coated media at higher dust charge levels showed better filtration results.

Dielectric characterization and conduction modeling of polymers are considered important owing to increasing use of polymeric insulation worldwide in power cables for electric power distribution. Electric conduction in polymers is a complex phenomenon and differs considerably at high electric fields where phenomena like space charge formation and charge injection from the electrodes come into the picture. This paper investigates the charge injection during polarization and subsequent discharging of low density polyethylene (LDPE) films at high electric fields (> 10 kV/mm) and under different temperatures. An attempt was made to study the short term Debye-type exponential behavior and long term power law behavior. Apart from the variation in the power law exponent for absorption current with increasing field, anomalies were noted in both types of relaxation currents at high electric fields and temperatures. Evidence of the polarization current anomaly was correlated with space charge behavior of samples. Interestingly, the space charge evolution under step voltage application was observed to be oscillatory in some cases, wherein, the charge trapping inside the dielectric bulk showed an oscillatory profile. The experimental factors which could contribute to anomalous discharging currents have also been thoroughly investigated and reported, which seem to have not been paid attention until now.

All real-time signals observed from various measurement systems require signal-processing techniques like the deconvolution, to compensate for the effect of transfer function of the systems. Wiener deconvolution is a widely used signal-processing technique for signal restoration. Often, if the power spectral density of signal and noise is unknown, the accuracy of the restored signal depends on an unknown filter parameter. In the literature, time-consuming, iterative, computational methods were reported to estimate the parameter. However, many of these methods give a range of optimum values instead of an unique value and often lead to either over-smoothing or under-smoothing. In this paper, novel analytical expressions are presented through which the unknown parameter can be estimated explicitly. The analytical results of this study are compared with the numerical methods, and they are found to be accurate and robust against numerical evaluation. Further, the results are demonstrated for signals obtained experimentally from the pulsed electroacoustic system and a network, in authors’ laboratory.

When operating under alternating current fields, the capacitive effect of cable insulation takes precedence over the resistive effect and its permittivity assumes a higher importance compared to electrical conductivity towards the distribution of electric field. Research in the past has shown that relative permittivity of a dielectric has a dependence on operating temperature, electric field and frequency. In this paper, the authors present a study on the effect of temperature and field dependent, non-linear permittivity on the resultant radial electric field distribution in case of a multi-dielectric insulation system in a two-dimensional cylindrical geometry. The effects of permittivity coefficients, conductor boundary temperature and applied average electric field on the distribution and peak of resultant field have been investigated. The authors believe that these results will prove to be useful in selection of additional layers of insulation in multi-dielectric power cables and cable joints.

In HVDC power transmission, power cables are taking the place of overhead lines at a rapid rate. While testing HVDC power cables, manufacturers often encounter difficulty of handling, as a prior knowledge of the time at which the power cable would discharge completely is not known. This paper explores the discharging time of cables of different lengths and also analyzes the factors which affect the discharging phenomenon, and tries to give a proper time after which a tested cable can be handled safely. The complexity arises because of the fact that a cable behaves as a distributed parameter transmission line. The discharging phenomenon has been simulated using PSPICE software and also some of the results are verified analytically.

One of the most strenuous task is to locate the position of fault in power cables. There are many techniques which are available to locate faults, but each one have its own advantages and disadvantages. Contrary to the conventional reflectometry based methods, this paper explores a technique based on Sweep frequency response analysis (SFRA) in which reflection of the wave are not required. Sweep frequency response analysis (SFRA) are mostly used in transformer for checking the healthiness of its winding and to locate different faults and defects in it. In this paper using the same concept of SFRA in transformer, detection and location of fault in a cable has been investigated using PSpice simulation.

In this paper, dc electrical treeing breakdown experiments are conducted using needle-plane system. Electrical treeing test can be used for the assessment of life estimation of the insulating material by estimating the voltage endurance coefficient and accumulated damage. Damage equalization method (DEM) is used for estimating the life of the dielectric material used in HVDC cables. Breakdown experiments are conducted with progressive voltage steps of different step size. Interesting new results on the role of different step size on breakdown voltage is reported which in turn shows the effect of space charge injection and accumulation. The results from the space charge distribution in a plane-plane geometry justify the authors’ results on the effect step size on dc breakdown in needle-plane geometry. The experimental results obtained are compared with data available in the literature for ac electrical treeing tests for different rate of progressive voltage rise.

Ageing is a slow process of degradation of dielectric properties of cable insulation operating at high thermal stress. Prolonged thermal stress gradually weakens the insulation and ultimately leads to failure. Therefore, ageing studies are important for the design of insulation for high voltage power apparatus. One of the important properties of insulation is the resistivity of the material, especially for use in DC systems. In this paper, the authors have considered volume resistivity as a parameter to identify the changes with respect to ageing time. The ageing of insulation, change in volume resistivity and V-t characteristics are believed to be related. A batch of fresh LDPE samples was subjected to thermal stress for different time durations and the volume resistivity and permittivity of each of the samples had been measured under different electric fields. The variation in volume resistivity was analyzed experimentally and theoretically. An attempt has been made to relate endurance coefficient to changes in resistivity. Endurance coefficient has been estimated using volume resistivity.

Inductors utilizing the nonlinear properties of ferromagnetic materials may also be made to perform as switches. These function as magnetic switches which decrease the circuit impedance for the compression of current pulses in time domain. These have been employed in pulsed power applications such as radars and lasers. The nonlinear inductor being robust, relatively inexpensive and having a comparatively long lifetime, have an advantage for operation in certain applications over the conventional switches. In this paper, the authors have developed a magnetic switch which utilizes an inexpensive and readily available material – M5 electrical steel as saturable core.

Space charge always assumes critical importance when it pertains electro-thermal problem of a dielectric subjected to dc stresses for dc cable insulation in particular. The significance of space charge only increases when multilayer dielectrics, cable joints in particular, are concerned. Interfacial polarization, complex electric field distribution and dynamic boundary temperatures greatly increase the probability of breakdown of a multilayer dielectric. Hence as an extension to the authors’ previous works this paper focuses on computation of space charge and its effects related to electric field and temperature profiles of a multilayer dielectric. Poisson’s equation along with Maxwell-Wagner interfacial polarization equation were used to obtain space charge distribution at different boundary temperatures and fields. Net charge accumulation in individual layers at different boundary temperatures and fields were determined.

Pulsed electro-acoustic measurement system is one of the versatile systems for measurement of charges accumulated in dielectric materials. The charge is measured as a voltage signal observed at an amplifier output which gets input from an acoustic sensor. Because of limited frequency bandwidth of the acoustic sensor and amplifier, all experimentally acquired signals require processing technique like deconvolution to estimate original signal (charge). Due to presence of noise in all experimental signals, deconvolution turns out to be an optimization problem. The optimum deconvolution involves estimation of optimum value of a deconvolution parameter, also known as regularization parameter. This parameter controls the tradeoff between signal distortion and noise minimization. In literature, several methods were suggested for estimation of optimum value of regularization parameter. However, each method yields a different estimate for the parameter. In this paper, the suitability of these conventional methods is investigated for estimation of space charge. Also a simple, yet, better estimation method, specific to space charge estimation, is presented. Interesting results and discussion on efficacy of these methods against, simple spectral division followed by Gaussian filtering, is also presented.

Conventional constant-stress accelerated ageing tests are time consuming, cumbersome and suffer from the disadvantage that some samples may not fail even after a long time. This necessitates censoring the data for life estimation, increasing the complexity of data analysis and leaving some amount of uncertainty due to censoring. Step-stress breakdown tests for life estimation were already proposed in the literature. Complex Weibull statistics were resorted to for life estimation. In this paper the authors present a different data analysis procedure i.e. damage equalization method for estimating the life of power equipment. Inverse power law model is used in conjunction with Miner's cumulative damage theory. Also, the procedure suggested is much simpler than the previous procedures, which involve solving a complex maximum likelihood function for which non-linear techniques like Newton-Raphson method is required. The approach is further compared with existing techniques of life estimation and found to be matching well. Life estimation of cables supplied by a local manufacturer for dc voltage applications has been performed. Several types of breakdown experiments were conducted for cables, with different step-size of step-stress accelerated ageing tests, in authors' laboratory, at two distinct temperatures. In addition, tests were also conducted on low density polyethylene samples.

The space charge phenomenon in PE (polyethylene) particularly in LDPE (low density polyethylene) is being widely researched for more than two decades. Despite various theories proposed by researchers, the charge dynamics in general and charge packets in particular, inside the polymeric insulation are yet to be completely known. The authors have investigated the dependence of charge dynamics on electric field using PEA (pulsed electroacoustic) technique. The experiments were carried out at 25 °C on 100 μm LDPE film samples under applied electric fields of 100–150 kV/mm. External current measurements were also performed under similar conditions. The analysis of charge profiles and external currents shows that apart from other factors, charge formation and polarity of charge also depend on history of electric field application. Interesting observations were made on the consequence of such results. Experiments were performed repeatedly on virgin samples, taken from same lot, and the results were found to be almost same. It is believed that the effect of history of voltage application on charge formation, presented in the paper, is useful for understanding practical behavior of LDPE which, if used in power cables, is expected to serve as a dielectric for several years — accumulating a lot of history of voltage application.

Low Density Polyethylene(LDPE) is considered as an important material for the insulation in high voltage dc. The knowledge of conduction current and in LDPE material is quite vital due to the fact that it is related to charge accumulation in it. To understand the whole information of conduction current and space charge accumulation, we have been trying to construct a new method where the measurements are performed using a guarded three-terminal electrode system. Traditionally, the measurement of conduction current was done on the ground electrode due to safety reasons. With the advent of wireless technology such as Zigbee modules etc, the measurement at high voltage electrode is also possible. So by taking dielectric sample as LDPE, we have been trying to find the conduction current and space charge accumulated in it.

Paper insulated cables were the first commercially used cables and they continue to be in service even today owing to their long history of reliability. Under repeated load cycling and varying electric stress and temperature, however, the dielectric properties of the cable undergo changes. In this work, the relative permittivity of paper insulation from a used and aged oil impregnated paper cable has been measured at different electric fields and temperatures using dielectric spectroscopy. Electric field along the radius of the cable has been obtained using a software based on finite element method. The results obtained through dielectric spectroscopy have been used to input the properties of the cable paper insulation in the software. A comparison of the radial electric field distribution inside the paper cable has been made for two cases; one where the relative permittivity of insulation is dependent on temperature and electric field and the other where it is independent. The results of this work may prove to be useful for monitoring of ageing cables and for cable joints involving paper cables.

Low density polyethylene (LDPE), a promising member of polyethylene dielectric family, majorly used in high voltage direct current (HVDC) cables. Even with their associated advantages of excellent quality of insulation, LDPE suffers from the problems of space charge and leakage current, which directly and indirectly affect the performance of the insulator. As far as leakage current is concerned, various models have been put forth which explain the charge transfer mechanisms on the structural basis of LDPE. It was suggested in these mechanisms, that LDPE can be fully assumed as full of high density of traps, while completely neglecting its semi crystalline structure. In this paper detailed atomic level analysis of structural features of LDPE has been presented along with their respective influence on transportation of charge carriers. Among different structural regions of LDPE, which region play a dominant role in determining the conductivity of material, is also discussed.

In this work, an attempt was made to study the spatial charge distribution in fibrous dielectrics using pulsed electro-acoustic method. The polarized dielectrics displayed in-depth charge polarization and exhibited slow charge decay. The initial charge density was found to increase with an increase in polarization voltage as well as polarization time. The statistical analysis revealed that though the polarization voltage affected the initial charge density significantly, the polarization time was insignificant. A multiple linear regression model of initial charge density was developed and found to predict the experimental results quite satisfactorily.

High voltage direct current (HVDC) cables widely use low density polyethylene (LDPE) as main insulation because of its associated advantages. Though, it has been underlined that, it displays non-linear conduction current (charge transport in dielectric) when used under high electric field. Different charge transport models have been proposed for understanding the conduction current in LDPE, such as Pool-Frenkel, Hopping model, Schottky model etc. These models explain the process of charge transfer through the material; using different kinds of traps present [1–4]. In this paper comparative study has been done for famous charge transport models with experimentally obtained conductivity for a wide range of electric field (20 kV/mm to 200 kV/mm) and at different temperatures (30° C, 50° C).

Cable joints are one of the examples of multilayer dielectrics. Joints are subjected to high electric and thermal stress, the former depending on the cable itself, while the latter is a consequence of ohmic losses in a conductor due to load current and leakage current flowing through the layers of the insulation. This coactive effect might cause the cable joint to undergo thermal/electrical breakdown at some point. Hence the estimation of Electric fields at maximum thermal voltage of cable joint/multilayer dielectrics in general, is of quite significant importance. Current continuity equation, heat flux equation and Poisson's equation along with appropriate boundary conditions were simultaneously solved at various current densities by finite difference method and voltage versus current density is plotted. The peak value of voltage, after which the solution of temperature goes haywire is the Thermal Maximum Voltage and electric field distribution and temperature distribution at that voltage/current density are investigated.

This paper deals with the novel hybrid technique for solving the IEEE distribution system in the existence of the distributed generation (DG). This hybrid technique find the optimum network reconfiguration to minimize the real power losses along with voltage profile improvement A novel hybrid (heuristic and meta-heuristic) technique is used for finding out the optimal configuration for a network. This technique is compared with Selective particle swarm optimization (SPSO) and Artificial Immune System optimization (AIS). The meta-heuristic technique (AIS) generates the initial topologies of the distribution and the branch exchange method helps in improving the chromosomes generated by the AIS. The major factor to characterize the capability of a hybrid algorithm with other meta-heuristic algorithms network and heuristic technique (branch exchange) is the effective run time. The effectiveness of the all approaches is used with IEEE 16, 33 and 69-bus test systems with invigorate results.