Jenkins’ Deliberations on Communal Conflict with the Leaders of Punjab: 1946-47 (Part-II)

Bhim Sen Sacher informed Jenkins about the destruction caused by arson in Lahore. Akbari Mandi, Chune Mandi, Chauhatta Basti, Bhagat Singh Basti, Kucha Kagzian and Pipal Vehra had been burnt down. The fire brigade could not cope with those vast and dispersed areas. If someone tried to extinguish the fire he was shot at by the police. Bhim Sen Sachar suggested that the only way to save Lahore was to impose martial law in the city. He hoped that the Governor would take that step immediately.64 Jenkins thanked Lala Bhim Sen Sachar and Gokul for their letters informing him about Lahore. Jenkins explained that fire brigade had done a good job in spite of constraints and difficulties. He believed that all communities had access to incendiary materials, and could use it without detection by traversing joined roof-tops. Throwing fire-balls from one house to another was wreaking devastation. Checking trouble of that kind was not an easy job, but searches were carried out and culprits were arrested.6

Analysis and Design of Neural Network Controller of Single Active Bridge Converter

The power electronic researchers and designers are involved since last two decades in designing converter topologies for their effective use in high power applications. Recently, developed SAB converter being an advanced topology is gaining popularity because of its many attractive features. Despite of its attractive characteristics and merits it faces a serious problem of the generation of oscillations. These oscillations create disturbances in the systems network and also badly affect the performance of the converter itself. Such topologies with conventional controllers are also produce power quality problems such as; variation in frequency, voltage dips and swells, which lead to interruptions and transients in system networks. As it is a well known fact, that SAB converter is a variable structure system due to its switching operation and contains nonlinearities. Because of the high switching speed of SAB converter, i.e. in nano seconds, it is difficult to control it with linear controllers. In previous research the Proportional plus Integral (PI) controllers were used which were unable to control the SAB converter under nonlinear situations and ultimately this will lead to undesired results. Considering the deleterious effects and limitations of the conventional controllers in this research the Neural Network based controller is designed to handle the non-linear situations. Neural Network Controller (NNC) is recently found various applications in power electronic converters because of its good dynamic behavior and robustness. Designing of the Neural Network Controller for SAB converter is the main contributions in this research work. The NNC type cascade controller for SAB converter is successfully developed in MATLAB. The performance of single active bridge topology with NNC is tested under steady state, transient and dynamic region by considering the, line, duty ratio and reference voltage variations. Simulation results show improvements in transients and reference variation in the range of 26% to 38% respectively and 6 time improvement in line variation and 30 time improvement in duty ratio variation. The designed controller after through analysis, testing and comparison with previous designed controllers depicts that the neural network based controller is quite effective, efficient and has good transient and steady-state properties. Keywords: DC/DC converters, Single-Active Bridge converter, Neural Network Controller, Feed Forward Neural Network.