Ewald F. Fuchs - Introduction to Energy, Renewable Energy and Electrical Engineering

jcomplex number operator indicating imaginary part of phasor, unit component of (i, j, k) rectangular systemjωLreactive impedance of inductance LjωL1reactive impedance of self‐inductance L1jωL2reactive impedance of self‐inductance L2jωMreactive impedance of mutual inductance MJAZJahresarbeitszahl (German for seasonal performance factor of heat pump)Junit of energy joules current density

kunit component of (i, j, k) rectangular system, coupling coefficient of two windings/coils, kilo, Boltzmann constantkrad/skilo radians per second(keΦ)field flux of DC machineK1constantK2constantKCLKirchhoff’s current lawKVLKirchhoff’s voltage lawkVAkilovolt‐amperekgkilogram is unit of masskg‐forcekilogram‐force is unit of weightKkelvin

lleakagelxluxlengthcoreiron‐core lengthlimitsymbol for limiter or limit operationlengthtotal length of turnLlighting, lower, line, symbol for inductanceLaarmature inductance of DC machineLsself‐inductanceLmmutual inductanceLPlow passLVlow voltageL11self‐inductance of primary winding 1L12mutual inductance between winding 1 and winding 2L21mutual inductance between winding 2 and winding 1L22self‐inductance of secondary winding 2L1self‐inductance of primary winding 1 when L1 = L11L2self‐inductance of secondary winding 1 when L2= L22lciron‐core lengthLEDlight‐emitting diodeℓleakage, general subscript for vector potential Aℓℓcorecore lengthℓgair‐gap lengthlagginglagging power factor (e.g. current lags voltage)leadingleading power factor (e.g. current leads voltage)lblibrum (Latin for pound)L‐Lline‐to‐lineL‐Lsecondary_rmssecondary line‐to‐line root‐mean‐square valuelightinglighting parameterlighting_rmsrms value of lighting parameter (e.g. voltage)lmlumenloadoldindicates load (load) before (old) power factor correctionloadnewindicates load (load) after (new) power factor correctionLHSleft‐hand sideLmmutual/magnetizing inductance of T‐equivalent circuitLℓpleakage inductance of primary winding leakage inductance of secondary winding referred to primary side of transformerLNGliquid natural gasLPGliquid petroleum gas, propaneλflux linkages

mmilli, mechanical, magnet, unit of meter, magnetizing, motor, slope of a linear functionMmutual inductance if L12 = L21 = M, stands for main power system, megammfmagnetomotive forceM(ω)magnitude of phasor transfer function G(jω) as a function of angular velocity or angular frequency ωMATLABsoftware of the US American company MathWorks for the solution of mathematic problemsmaxmaximummicro10−6milli10−3msmillisecondsmHmillihenriesmVmillivoltsmAmilliampereMHDmagneto‐hydro dynamicMKSAmeter‐kilogram‐second‐ampere system of unitsMKSAKmeter‐kilogram‐second‐ampere‐kelvin system of unitsmmfmagnetomotive forceMOSmetal‐oxide semiconductorMOSFETmetal–oxide–semiconductor field‐effect transistorMPPmaximum power pointMWmegawattMVAmegavolt‐ampereμpermeability of (magnetic) material, 10−6μ = 4π10−7 H/mpermeability of free spaceμrrelative permeability of (magnetic) material

nneutral, running index, ±1, ± 2, ± 3, …nsneural point of secondary winding connected in wyenpneural point of primary winding connected in wyenmmechanical speednloadneural point of wye‐connected loadnano10−9Nnorth (pole), neutral, Norton, running index, subscript for numerator, number of turnsN(jω)numerator of transfer function G(jω)N1number of turns of primary winding (1) of transformerN2number of turns of secondary winding (2) of transformerNpprimary number of turns of transformerNssecondary number of turns of transformerNInoninverting configuration of operational amplifierNASAUS National Aeronautics and Space AdministrationNdFeBneodymium–iron–boron magnet materialNMOSn‐type metal–oxide–semiconductorNOCTnominal operating cell temperatureNorton theoremimpressed current source theoremNRELNational Renewable Energy Laboratory

ocopen circuitOPoperationalORCorganic Rankine cycleoutoutputωangular frequency or angular velocityωangular frequency or angular velocity at resonance, undamped natural angular frequency, center frequencyωmmechanical angular velocity reference/nominal/rated (*) value of mechanical (m) angular velocityωHIupper (HI) break or cutoff frequency, half‐power angular frequencyωLOlower (LO) break or cutoff frequencyωLO, ωHIhalf‐power frequenciesΩunit for ohmsωLloadreactance due to load inductanceωLload1reactance due to load 1 inductanceωLload2reactance due to load 2 inductanceωMmutual reactance due to coupling of two windingsωL1self‐reactance of winding 1ωL2self‐reactance of winding 2 reactance due to load impedance referred to primary side per phase reactance of delta‐connected first load per phase reactance of delta‐connected second load per phase reactance of Y‐connected first load per phase reactance of Y‐connected second loadωLlsleakage reactance of secondary windingωLls ′leakage reactance of secondary winding referred to primary side of transformer per phase reactance of delta‐connected loadωLlpleakage reactance of primary windingωLmreactance of magnetizing/cross‐branch of transformerωLlineper phase reactance of distribution/transmission lineωm(t)time‐dependent mechanical angular velocity

ppole, peak, parallel, primaryPperformance, phosphorous, proportional control, average or real power, proportional poles of transfer function G(jω) from 1, …, nPDproportional–differentialPIproportional–integralPIDproportional–integral–differentialP1input real powerP2output real powerPFpower factorp(t)instantaneous powerPratrated real output powerPactualactual real output powerpin(t)input power as a function of timepout(t)output power as a function of timePininput real powerPoutoutput real power copper loss of primary winding copper loss of secondary windingPfeiron‐core lossPCCpoint of common couplingphphasePLLphase‐lock loopperperiodPFdisplacement or fundamental power factorPEMproton exchange membranePEMFCproton exchange membrane fuel cellpico10−12phasermsphase (phase) root‐mean‐square (rms) valuePMpermanent magnetPMGpermanent‐magnet generatorPMMpermanent‐magnet machinepnpositive and negative typesppmparts per millionPSPICEPersonal Simulation Program with Integrated Circuit Emphasispuper unitPVphotovoltaicspwpulse widthpw/perpulse width per periodPWMpulse‐width‐modulatedposcillation(t)oscillating powerπpi, or 3.141 59…