Voltage sag compensation at load side in armor fighting vehicles using ultra capacitor

Purpose The purpose of this paper rapid development of various voltage sag compensation techniques in DC bus using ultra-capacitors (UCs) provides satisfactory results when compared with required peak power demand for shorter duration. Later, UCs have been used as floating capacitors [1] [2]. Various UCs are available based on internal resistances which also rely on its manufacturing materials, similar to double layer capacitors. Design/methodology/approach This paper demonstrates UCs based voltage sag compensation at load side under different working modes of hydraulic pack (HP) in an armored fighting vehicle (AFV). The main sources to supply the HP are 24 V, 400 Ahr battery bank and 20 kW main generator. HP is considered to be the highest power load of a system. 2,500 A inrush current was drawn by HP during initial conditions, and also, this system works in both elevation and azimuth mode. Voltage sag has been varied from 15 to 24 V for different modes. But as per the military standard, electrical systems should operate between 18 and 32 V DC. Because of insufficient terminal voltage, required energy cannot be attained and supplied to the loads. The proposed topology compensated the voltage sag and maintains nominal voltage on a DC bus. The devised circuit has been verified under all possible operating loads such as continuous, intermittent and momentary. The same has been simulated using MATLAB/Simulink and was experimentally verified. The minimum voltage maintained in a DC bus is 22.2 V in simulation, while experimentally, it was 24.2 V. Findings For getting higher percentage of efficiency, secondary energy system configuration, mainly designed for electrical vehicles, is needed. It was implemented and same was tested with the fighting vehicle system[1]. The proposed configuration comprises of bank of an UC and a battery bank. The system was finally implemented in AFVs. Originality/value The goods vehicles made of UCs can hold very minimum energy because of minimum density of energy. The modified AFV can have minimum charging as well as discharging of rate of energy and, thus, power[3][4]. Thus, the proposed idea of modified vehicle system has influence over significant change in the state of charge.