KEB COMBIVERT F4-C Applications Manual

Also see for COMBIVERT F4-C: Instruction manual

Contents

3ANTRIEBSTECHNIK2 1 3KEB COMBIVERT F4-CName: Basis09.04.992© KEB Antriebstechnik, 1999All Rights reservedProduct Description SummarySection PageDate Chapter=~ =~UN R C WUVUZKL1L2(L3)M3 ~2.1.1 Features of KEBCOMBIVERT F4-C2.1 Product DescriptionKEBCOMBIVERTF4-C8 parameter sets11 parameter groupsProg. Operator menu2 prog. relay outputs4 prog. digital inputs1 prog. digital output1 prog. analog output2 prog. analog inputsHardware current limitAutoboostSlip compensationDC-brakingJogging-function (prog.)Speed searchPower-Off functionDRIVECOM-compatibleEnergy saving functionPI-controllerProtective equipmentElectr. motor protectionProg. filter for analog and digital inputsSoftware In-/OutputsAdjustable balancing of the rampsHour meter2.1.2 FunctionPrincipleThe power circuit of a frequency inverter consists basically of a mains rectifier, theDC-link and an inverter at the output. The mains rectifier consists of an uncontrolledsingle or three-phase bridge connection, the single-phase design is restricted to smallpowers. It converts the AC-voltage of the mains into a DC-voltage, which is smoothedby the DC-link capacitor, thus in the ideal case (inverter unloaded) the DC-link ischarged with a voltage of UZK = √2 . U N.Since during the charging of the DC-link capacitor very high currents flow for a shorttime which would lead to the tripping of the input fuses or even to the destruction ofthe mains rectifier, the charging current must be limited to a permissible level. This isachieved by using an inrush current limiting resistor in series to the capacitor. Afterthe charging of the capacitor is completed the limiting resistor is bridged, for example,by a relay and is therefore only active at the switch-on of the inverter.As the smoothing of the DC-link voltage requires a large capacity, the capacitor stillhas a high voltage for some time after the disconnection of the inverter from themains.The actual task of the frequency inverter, to produce an output voltage variable infrequency and amplitude for the control of the three-phase AC motor, is taken over bythe converter at the output. It makes available a 3-phase output voltage according tothe principle of the pulse-width modulation, which generates a sinusoidal current atthe three-phase asynchronous motorMains rectifier MotorConverterDC-linkPicture 2.1.2 Block diagram of an inverter power circuit2. Overview