30 Operation principle and hardware descriptionOperation principleThe ACL30 elevator drive is a wall or cabinet mountable drive for controlling anasynchronous motor or a permanent magnet motor. The following components definethe operation of the drive. See the main circuit on page 30. Main circuitComponent DescriptionRectifier Converts the three-phase AC voltage to DC voltage.Capacitor bank Stores energy which stabilizes the intermediate circuit DC voltage.Drive Converts DC voltage to AC voltage and vice versa. The motor is controlledby switching the IGBTs of the drive.Brake chopper Conducts the energy generated by a decelerating motor from the DC bus toa braking resistor. The brake chopper is built in the ACL30. Brake resistorsare external options.Brake resistor Dissipates the regenerative energy by converting it to heat.Mains choke Reduces• harmonics and r.m.s in the input current• supply disturbance and low-frequency interference.Mains filter See page 339.Motor outputBrake chopper (see chapterResistor braking onpage 343)+ –UDC+ UDC– V1 W1U1V2 W2U2 R– R+AC supplyACL30DriveCapacitor bankRectifierCHK-xx mains choke (seechapter Mains chokes onpage 335)JFI-xx EMC filter (see chapterEMC filters on page 339)JBR-xx brake resistor (seechapter Resistor braking onpage 343)
