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Relative to conventional self-contained battery technologies, there are many advantages for VRFB using on large, utility-scale bulk energy storage application. During design the large scale VRFB system, the reduction of shunt current has always been focused on. The paper explored a stacks string model based on MultiSim™ software package to analyze and optimize shunt loss. Numerical analysis and optimization result express that the extra pipe resistance breaks the straight-line manifold voltage distribution, the degree of voltage redistribution depends on the resistance of stack feed piping, and shunt geometry optimization ranges are often limited by constrains and considerations.

Design, fabrication and measurement of a filtering antenna are presented for WLAN / WIFI/ LTE communication systems in this paper. The filtering antenna consists of a feeding network, half-wavelength (λ/2) uniform impedance resonator (UIR) with a cambered structure and an annular slot. UIR with cambered structure is employed as the first stage resonator to improve the frequency selectivity in necessary passband. An annular slot etched on the back of substrate is excited by UIR through an inset coupling structure. The annular slot acts as a radiator as well as the last stage resonator. The inset coupling structure can be treated as the admittance inverter in the filter design. Compared to conventional antenna, the proposed filtering antenna has wide bandwidth, low cross polarization and good frequency skirt selectivity in passband. Measurement results show that the filtering antenna can operate at 2.5GHz with 550MHz, peak gain can be obtained to 1.2dBi, cross polarization can be suppressed to −30dB, respectively. The filtering antenna only occupies 0.23λ g × 0.29λ g .

A compact ultra-wideband (UWB) antenna with sharp band-notched characteristics and controllable notched bandwidth is presented. The proposed antenna consists of an inverted U-shaped slot on the ground plane and a radiation patch similar to the slot which is fed by a 50-Ω microstrip line. By slitting an inverted U-shaped slot on the radiation patch and embedding an inverted U-shaped strip near the top edge of the ground aperture, a second-order notched band of WLAN (5.15–5.85GHz) is achieved. Compared with the traditional band-notched antenna, the selectivity of the notched band is greatly improved. Moreover, the bandwidth of either the lower or upper rejected band can be independently adjusted by changing the size of the slot and the strip, respectively. The antenna is fabricated on a standard low-cost FR4 substrate with a whole size of 27∗20∗1 mm3. Good agreement is achieved between simulated and measured results.