Effect of Different Load Resistances on 3- Stage Type-A Pulse Forming Network | Open Access Journals

ISSN ONLINE(2278-8875) PRINT (2320-3765)

Effect of Different Load Resistances on 3- Stage Type-A Pulse Forming Network

Ramnik Kour1 and Randeep Singh Chib2
  1. M. Tech Student, Dept of EEE, Arni University, Kathgarh, Himachal Pardesh-176401, India
  2. Assistant Professor, Dept of EEE, Arni University, Kathgarh, Himachal Pardesh-176401, India
Related article at Pubmed, Scholar Google

Visit for more related articles at International Journal of Advanced Research in Electrical, Electronics and Instrumentation Engineering

Abstract

In this paper, a 3-stage type-A pulse forming network have been studied and designed to evaluate the effect of output parameters for different load resistance values. The results are evaluated for different load resistance value while keeping the other components value as static. The reference impedance was set to 50Ω. The high input applied voltage of 1KV is considered for the design and result evaluation purposes. The results are evaluated to see the effect of load current (IZ), capacitor current (IC) and inductor current (IL) for different load resistances.

Keywords

Pulse forming network, type A network, ladder network, load current.

INTRODUCTION

The pulsed power is the instant energy released after accumulation for a longer period of time through a switch [1]. The characteristics of this power pulse are based on the load requirement and specification that includes its voltage level and rising time [2]. In the past, pulsed power generators have been generally specified for navigation and nuclear fusion applications [3]. High peak power were used for these purposes whereas moderate peak power are used mainly for industrial applications like food processing, medical and water treatment, ,pulsed high-current linear accelerators, insertion of protein into cell membrane, exhaust gas treatment, gas discharge experiments , engine ignition, and ion implantation [4-9].
image
Some common technologies that have been utilized for pulsed power supply are Marx Generators (MG), Magnetic Pulse Compressors (MPC), Pulse Forming Network (PFN), Multistage Blumlein Lines (MBL) [10-12]. Several researchers had reported the applications and problems related to PFN and their applications [13]. PFNs consist of the lumped-constant network and are made up of cascaded low-pass LC-filters with non linear phase characteristics. PFN networks generally produce slope waveform at the trailing edge of the output pulse [14]. Since a PFN is an electrical circuit consisting of some switches capacitors, inductors, resistors, and treatment chamber, thus, the shape of a pulse depends on the electric values of each component [15]. Different types of PFN network are being designed that includes Type A, Type B, Type C, Type D, Type E, Type F and Rayleigh line [16]. In this work, Type A ladder network has been studied, analysed and modified to generate pulse waveforms. Further, the value of each component is to be optimized for their applications in high voltage pulse forming networks.

MATHEMATICAL ANALYSIS

Type-A network consists of a series combination of resistor and inductor in parallel with a capacitor is shown in fig. 2.
image
The resonant frequency for a single stage Type A network can be evaluated as [17]
image
For such networks, the resonant frequency is that at which the value of admittance is zero for imaginary part. Also the impedance (Z) is given as
image
Its magnitude is found to be
image
and the phase Angle
image
Pulse Width T is given as
image
Hence the fundamental components for type-A network are formed by the combination of L’s and C’s. The other elements are used to filter the fundamental shape.

METHODOLOGY

The design of the type-A PFN network can be explained using the flow chart as shown in fig. 3. The network is initiated by applying high ac voltage of 1KV. The input is then filtered and amplified and is then applied to 3-stage PFN network. The remaining dc component, if any, is again filtered out and the output is generated for the load greater than or equal to 1mA.
image
In this work, the type-A ladder has been studied and simulated for various ladder networks and component parameters. Only 3-stage networks have been simulated for this experiment to know their effect on various output characteristics. Figure 4 shows the n-ladder network for type-A network.
image
For this type of network, equicells are used. The value of resistances R were selected as 1KΩ while for inductors L and capacitors C, the selected values are 1μH and 1pF respectively. Different load resistances RL were used to evaluate the parametric changes at output. Different loads were taken as 1Ω, 10Ω, 100Ω and 1KΩ. The input voltage applied to the network is 1KV ac voltage with time interval Tint of 50 μs.

RESULTS AND DISCUSSIONS

The results were taken to evaluate the value of load current IL, capacitor current IC and inductor current IL. The experiment was performed in FEM based software MATLAB. Fig. 4 shows the output values for 1Ω load resistance.
image
Similarly the results were noted while taken the value of load resistance as 10Ω and is shown in fig. 5. We kept on increasing the load resistance to see its effect on the component parameters. In this regard, the graphs have been noted on the value of load resistance 100Ω as shown in fig. 6.
image
From the plots, it is clear that the frequency response of the network is limited due to inductance in the connections and the energy storage capacitors. Moreover, the response of the circuit would be limited to such an extent that there would be no peak at all. However, the accuracy depends on values of the equivalent circuits with respect to the various components (i.e. series resistance, series inductance, shunt capacitances, etc). Knowing these values, it is a simple circuit calculation to determine the approximate frequency response or the load current of such a circuit built by these passive components, to get the desired waveform in a specific network.
The lesser is the value of load, higher is the rise and fall time for the circuit. The slow rise and fall time for across the circuit for higher load value is due to the increased leakage inductance of the circuit. The fundamental component of the waveform can be estimated by the primary capacitance and the series inductance of the circuit. The leakage and loop inductance make up a series inductance which is almost twice the designed value and cannot be changed [18]. The primary capacitance could be lowered to shorten the rise and fall time, but in doing so the peak voltage would drop to an unacceptable level.

CONCLUSION

The design is formed and studied for a 3-stage Type-A PFN network to produce any desired pulse shape. The experiment is done by changing the values of the network components as well as the load resistance. The plots described in the figures show a parabolic rise and fall and ultimately become constant. Moreover, the simulation results show no significant differences in the rise and fall time for different cases, with and without consideration of losses.

References

[1] S. Zabihi, F. Zare, G. Ledwich, and A. Ghosh, “A New Pulsed Power Supply Topology Based on Positive Buck-Boost Converters Concept,” IEEE Trans. Dielectr. Electr. Insul., 2010.

[2] H. Akiyama, T. Sakugawa, T. Namihira, K. Takaki, Y. Minamitani, and N. Shimomura, “Industrial Applications of Pulsed Power Technology”, IEEE Trans. Dielectr. Electr. Insul., Vol. 14, pp. 1051–1064, 2007.

[3] H. Akiyama, S. Sakai, T. Sakugawa, and T. Namihira, “Invited Paper-Environmental Applications of Repetitive Pulsed Power”, IEEE Trans. Dielectr. Electr. Insul., Vol. 14, pp. 825–833, 2007.

[4] H. Mirzaee, A. Pourzaki, H. Mirzaee, A. Pourzaki, “Designing and Manufacturing High Voltage Pulse Generator with Adjustable Pulse and Monitoring Current and Voltage: Food Processing Application” World Academy of Science Engineering and Technology, 2011.

[5] Sun-Seob Choi,Gak Hwang Bo and Whi-Young Kim, “Starting current applications for magnetic stimulation” Journal of magnetic, pp. 51-57, 2011.

[6] Michael G. Mazarakis, et al, “High-Current Linear Transformer Driver Development at Sandia National Laboratories” IEEE Transactions on Plasma Science, Vol. 38, no.4, 2010.

[7] Rishi Verma, A Shyam and Kunal G Shah, “Design and performance analysis of transmission line based nano second pulse multiplier” Institute for Plasma Research, Vol. 31, pp. 597-611,2006.

[8] Matej Rebersek and Damijan Miklavcic, “Advantages and Disadvantages of differen concepts of Electroporation Pulse Generation” Vol.52, pp. 12-19, 2011.

[9] Deepak Gupta and P I John, “ Design and construction of double-Blumlein HV pulse power Supply” Sadhana, Vol. 26, Part 5, October 2001, pp. 475–484.

[10] T. Heeren, T. Ueno, D. Wang, T. Namihira, S. Katsuki, and H. Akiyama, “Novel Dual Marx Generator for Microplasma Applications”, IEEE Trans. Plasma Sci., Vol. 33, pp. 1205–1209, 2005.

[11] H. Li, H. J. Ryoo, J. S. Kim, G. H. Rim, Y. B. Kim, and J. Deng, “Development of Rectangle-Pulse Marx Generator Based on PFN”, IEEE Trans. Plasma Sci., Vol. 37, pp. 190–194, 2009

[12] D. Wang, T. Namihira, K. Fujiya, S. Katsuki, and H. Akiyama, “The reactor design for diesel exhaust control using a magnetic pulse compressor”, IEEE Trans. Plasma Sci., Vol. 32, pp. 2038–2044, 2004.

[13] R. Deepalaxmi, Praveen.J, Prasith .A, Prithieve.I, “Design of a Pulse Forming Network to Launch an Object Using Rail-Gun”, IJASETR 1(3), pp. 14-24, 2012.

[14] M. Akemoto, S. Gold, A. Krasnykhand, R. Koontz, “Design of a PFN for the NLC klystron pulse modulator”, High Energy Accelerator Research Organization (KEK) SLAC–PUB–7841 June 1998.

[15] Abbas Pourzaki and Hossein Mirzaee, “New High Voltage Pulse Generators,” Recent Patents on Electrical Engineering, Vol.2, pp. 65-76, 2009.

[16] Ding, W. and Marchionini, G. A, Study on Video Browsing Strategies. Technical Report. University of Maryland at College Park. 1997.

[17] M. E. Van Valkenburg, Introduction to Modern Network Synthesis. New York: John Wiley & Sons, 1960.

[18] W. R. Cravey and T. R. Burkes, "Design of Repetitive Very High Voltage Pulse Forming Networks of Short Duration," in Proc. IEEE Pulsed power conference, pp. 116-119, 1989.