Online collaborative estimation technology for SOC and SOH of frequency regulation of a lead-carbon battery in a power system with a high proportion of renewable energy

In this paper,a collaborative online algo-rithm is proposed to estimate the state of charge(SOC)and state of health(SOH)of leadcarbon batteries that participate in frequency regulation of a power system with a high proportion of renewable energy.The algo-rithm addresses the inaccurate estimation of energy storage battery states caused by continuous and alter-nating charging and discharging over a short period.Analysis of lead-carbon battery chemistry and materials reveals that the resistance of the diaphragm is the most influential factor in battery aging.In addition,the hyste-resis characteristics of an energy storage battery vary significantly between the charging and discharging stages.A second-order RC equivalent circuit model is proposed that considers the contact and diaphragm resistances,and hysteresis characteristics.Based on this,models for constant current charging interaction,constant voltage charging interaction,and dynamic discharging interaction are developed.The adaptive forgetting factor recursive least square(AFF-RLS)method is used to identify the parameters of the interactive models.Then an interactive multiple model with the embedded unscented Kalman filter(UKF)is used to estimate the SOC of the energy storage battery.The membrane and contact resistances identified by the interactive multi-model(IMM)are used to estimate the SOH,and online collaborative optimization of the SOC and SOH is achieved.The error of the proposed SOC estimation method is experimentally verified to be within 2%,which is less than 5%of the standard value,and the error of SOH estimation is within 0.5%,demonstrating the high accuracy of the proposed method.

Impact history and origin of lunar meteorite Northwest Africa 15528

No samples from the Moon’s far side have been returned to Earth.Thus,lunar meteorite study can deepen the understanding of the Moon’s far side(if we can identify which lunar meteorites came from the Moon’s far side).The Northwest Africa(NWA)15528 meteorite is a lunar feldspathic regolith breccia meteorite and we speculated it might originate from the Feldspathic Highlands Terrane(FHT)on the far side of the Moon.Here,we report detailed petrography,major and trace elements,and noble gas(He,Ne,and Ar)isotopes for the clasts and matrix,respectively.The results show that the NWA 15528 lunar meteorite contains diverse clasts,including anorthosite,granulite,basalt,and impact melt clasts.The coarse,wellcrystallized,uniform chemical composition minerals may come from intrusive plutonic rocks.Among the anorthosite clasts,the norite/olivine clasts originate from the deep lunar crust,whereas the other anorthosite clasts are from lunar highlands.The Sm concentrations in NWA 15528 were similar to those in the fourth group of Apollo 16 melt samples,demonstrating that NWA 15528 has a typical plagioclase highland meteorite composition.Compared with the Apollo sample data and remote sensing results,the chemical composition of NWA 15528 indicated strong affinities with the FHT area and ferroan anorthosite(FAN)material from the far side of the Moon.The noble gas isotopic composition of NWA 15528 is consistent with a binary mixture of solar wind and cosmogenic components;during stepwise pyrolytic extractions,we observed that the abundance of cosmogenic components decreased,whereas that of solar wind components increased with increasing temperature.The average cosmic-ray exposure(CRE)age of the matrix and granulite is 42±6 Ma,with a shielding depth in the same range of 10-20 g cm^(−2).The gas retention age of NWA 15528 is 2.14 Ga,and the antiquity age of NWA 15528 is(0.69-0.74)±0.2 Ga(considering 50%40Arm is 40Artrap)which indicates the different clasts of NWA 15528 are assembled after 0.69-0.74 Ga.