Synchronous motors up to 13.8 kV and up to 150 000 kW (horizontal, vertical, Ex ec / Ex pz)

Description

Every synchronous motor is designed for the parameters of a specific application, so the plant asks the customer to provide full data on the load and operating conditions. The calculations are run in software developed with the participation of European, American and Brazilian universities. A synchronous drive corrects the power factor by returning reactive power to the grid, holds constant speed under overloads and voltage fluctuations within the pull-out torque, has high efficiency over a wide range of operating modes and works reliably with frequency converters.

The motors run at constant speed, including in synchronous condenser mode, or at variable speed from a VFD. In the latter case they replace DC motors where high torque at low speed is needed. Versions with and without brushes are available, as well as with reduced starting current, which puts less load on the grid during starting and reduces mechanical stress in the windings. Vertical machines for pumps, crushers and mixers take significant axial forces and have oil-lubricated rolling bearings or sleeve bearings. For hazardous areas the manufacturer builds motors with Ex ec and Ex pz types of protection.

The frame is welded from steel sections and plates and withstands short-circuit forces and vibration. The stator core is laminated from electrical steel and the shaft is forged steel. The rotor is either cylindrical or has laminated or solid salient poles. Excitation is brushless, with a rotating exciter and the digital Sync-Rite™ module, which selects the angle and moment of excitation application by microprocessor, or static through slip rings and brushes. To check the module without disassembling the circuit, a portable tester can be ordered.

IC01 cooling corresponds to ingress protection IP23–IP24, while IC611 or IC511 with an air-to-air heat exchanger and IC81W give IP54–IP65. Forced ventilation and air supply through ducts are also possible. Stator coils are wound from rectangular copper wire with mica tape, and the Micatherm insulation system is impregnated by the VPI method with epoxy resins for voltages up to 13 800 V. Rotors are balanced at speeds up to 3600 rpm, as standard in two planes.

The standard package includes Pt-100 sensors for windings and bearings and heaters. Vibration sensors, current transformers for differential protection, surge arresters and surge capacitors, a lubrication station with shaft jacking, a pressurization system for Ex pz and partial discharge monitoring are added as options. Testing is done to NBR 17094-3, IEC 60034, NEMA MG 1 or API. The motors hold CSA, BVQI, ABS and DNV certificates and work in the mining, metallurgical, pulp and paper, chemical, petrochemical, cement and rubber industries, in water supply and in power transmission.

Technical specifications

Customs codes

Codes are for reference: the final code is determined at declaration for the specific model.

Questions and answers