Wanem em i 'Battery State of Charge' (SOC) Estimesen?

Bateri Stet bilong Sas (SOC) Estimesen

Elektrokemikel riaksen proses bilong ol pawa bateri em i kompleks, na i gat planti samting na yumi no save long en. Matematikel modeling bilong dispela proses em i wanpela multidisiplineri na multi-field problem, na i bin stap olsem wanpela ki lukluk na salens bilong tupela akademia na indastri. Input eksaitesen (lod karent) na autput obsevesen (voltej na tempereja) bilong wanpela pawa bateri em ol samting we ol i ken skelim long pawa bateri menesmen sistem. Stretpela modeling em i bikpela samting long tok klia moa long ol samting ausait long ol pawa bateri, disainim ol gutpela pawa bateri stet estimesen algorithm, na kamapim ol gutpela eneji menesmen sistem bilong ol nupela eneji kar. Ol komon pawa bateri model i save bruk i go long ol 'electrochemical' model, ol 'equivalent circuit' model, na ol 'machine learning' model.

Long namel bilong -1990s, M. Doyle, TF Fuller, na J. Newman bilong Yunivesiti bilong California, Berkeley, i bin kamapim wanpela 'pseudo-two-dimensional (P2D) model we i kamap long 'theory' bilong ol 'porous electrodes' na 'concentrated solutions', na dispela i putim as bilong kamapim ol 'electrochemical mechanism' model. Dispela model i yusim ol 'partial differential equations' na 'algebraic equations' long tok klia long 'diffusion' na 'migration' bilong ol 'lithium ions' insait long pawa bateri, ol 'electrochemical reactions' long pes bilong ol 'active particles', lo bilong Ohm, na 'charge conservation', na ol narapela samting bilong 'electrochemical'. I kam inap nau, planti ol 'electrochemical' model i kamap na kamap long dispela model. Wanpela 'electrochemical model' em i wanpela 'first-principles' model we inap long skelim gut ol samting ausait long wanpela pawa bateri tasol tu ol senis bilong ol samting insait long en (olsem mak bilong ol 'lithium ions' insait long ol 'electrodes' na 'electrolyte', na 'reaction overpotential', we i hat long skelim). Taim yumi skelim wantaim ol narapela pawa bateri model, ol 'electrochemical model' inap long tok klia long ol liklik samting insait long pawa bateri long bikpela dip na i gat moa klia mining bilong bodi.

Ol P2D model i gat planti kain samting na ol i ken skruim, ol i ken yusim long ol kain kain bateri wantaim ol narapela narapela materiel sistem, na ol i ken kamapim na skruim i go long ol moa kompleks multi-field coupling model. Olsem na, ol P2D model i save mekim bikpela wok tru long wokim ol bateri modeling. Tasol, ol i gat ol kompleks 'partial differential equations' na planti 'electrochemical parameters', na dispela i putim bikpela askim long ol 'computetional capabilities' bilong 'Battery Management System' (BMS). Nau yet, wok bilong stretim ol P2D model i save yusim ol namba rot, olsem 'finite difference method', 'finite element' rot, na 'finite volume' rot.

Ikwivalent seket model i yusim ol tradisenel seket elemen olsem ol 'resistor', 'capacitor', na ol 'constant voltage sources' long kamapim wanpela seket netwok long tok klia long ol samting ausait long pawa bateri. Dispela model i yusim wanpela 'voltage source' long makim 'thermodynamic equilibrium electromotive force' bilong pawa bateri, na wanpela RC netwok long tok klia long ol 'dynamic characteristics' bilong pawa bateri. Ikwivalent seket model i gat gutpela aplikesen long ol kain kain opereting stet bilong pawa bateri, na ol i ken kisim ol stet ekwesen bilong model, na dispela i helpim wok painimaut na aplikesen. Ol i bin yusim planti 'equivalent circuit model' long ol nupela eneji kar modeling na simulesen risets na model-bes BMS. Piksa 7-27 i soim wanpela kain ikwil seket model bilong wanpela pawa bateri we i gat n RC netwok straksa, ol i kolim n-RC model. Dispela model i gat tripela hap:

1) As bilong Voltej: Voltej bilong pawa bateri i stap op long $U_{oc}$.

2) Ohmic Internal Resistance: Kontak resistens bilong ol pawa bateri elektrod materiel, elektrolait, aisolesen resistor, na ol narapela komponen em i stap long $R_o$.

3) RC Netwok: Ol 'dynamic characteristics' bilong pawa bateri, wantaim ol 'polarization' na ol 'diffusion effects', ol i stori long en long 'polarization resistance' $R_p$ na 'polarization capacitance' $C_p$, we $i=0, ..., n_s$.

Long piksa 7-27, antap i makim 'polarization voltage' bilong pawa bateri.

Figure 7-27 n-stage RC model circuit structure

Long lukluk long 'voltage law' na 'current law' bilong Kirchhoff, na rilesensip namel long 'capacitor voltage change' na 'current', 'state-space equation' bilong 'circuit model' i ken kamap olsem:

7-50

Ol pawa bateri ikwivalent seket model olsem Rint model, Thevenin model, na Dual Polarization (DP) model em ol spesel kes bilong n-RC ikwivalent seket model taim n=0, n=1, na n=2, wanwan, na ol i bin yusim planti long pawa bateri stet estimesen na menesmen algorithm.

Ol masin lening model i no nidim save long intanel komposisen bilong bateri na ol spesifik riaksen mekanisme; ol i mas kisim tasol ol 'historical operating data' bilong bateri (karent, voltej, tempereja, na ol narapela samting). Tru tumas, ol i save kamapim ol 'nonlinear mapping functions' namel long ol 'variables' long rot bilong ol 'data-driven methods. Bikpela gutpela samting bilong dispela kain model em olsem em inap long yusim long ol kain kain bateri, em inap long mekim planti samting, na em inap long bihainim gut ol pasin bilong bateri.

Long sait bilong pawa bateri menesmen na kontrol, ol masin lening rot ol i yusim moa yet em ol 'fuzzy logic', 'neural networks', 'support vector machines', na ol 'combined algorithms' bilong ol. Long mun Mas 2016, win bilong AlphaGo long Go wol sempion Lee Sedol i putim nupela strong insait long dip lening, na kirapim nupela wev bilong risets na aplikesen, we ol i bin yusim tu long menesim ol bateri. Wantaim inap data bilong bateri bilong trening, dispela kain model inap long kamapim gutpela wok bilong prediktim samting. Tasol, dispela model i no gat mining long bodi, em i no inap long tanim, na pefomens bilong en i kisim bikpela hevi long namba na kwaliti bilong trening data, na dispela i mekim hat long tok tru olsem em i gutpela na strong taim ol i yusim long ol bateri menesmen sistem.