Abstract: A powered controlled acceleration suspension work platform hoist system for raising and lowering a work platform at a predetermined acceleration. The system incorporates several hoists attached to the work platform and in electrical communication with the motor control system. The motor control system is attached to the work platform and is in electrical communication with a constant frequency input power source and the hoist motors. The motor control system controls the acceleration of the work platform as it is raised and lowered by controlling the hoist motors. The controlled acceleration hoist system also includes a platform control system attached to the work platform that is in electrical communication with the motor control system and the hoist motors. Acceleration control is achieved by converting the constant frequency input power to a variable frequency power supply. This may be accomplished through the use of a variable frequency drive(s).

Abstract: The hoist control cooling system for preferentially cooling components of a variable frequency drive that is controlling a hoist motor. The cooling system includes an inverter temperature sensor, an ambient temperature sensor, a cooling system controller, an inverter cooler, and an ambient cooler. The inverter temperature sensor measures the temperature of the inverter and generates an inverter temperature signal. The ambient temperature sensor measures the temperature of the ambient air in the sealed control enclosure and generates an ambient temperature signal. The cooling system controller communicates with the inverter temperature sensor and the ambient temperature sensor by receiving the inverter temperature signal, the ambient temperature signal, and generating both an inverter cooling signal, and an ambient cooling signal. The inverter cooling signal controls the cooling of the inverter.

Abstract: A powered controlled acceleration suspension work platform hoist system for raising and lowering a work platform at a predetermined acceleration. The system incorporates several hoists attached to the work platform and in electrical communication with the motor control system. The motor control system is attached to the work platform and is in electrical communication with a constant frequency input power source and the hoist motors. The motor control system controls the acceleration of the work platform as it is raised and lowered by controlling the hoist motors. The controlled acceleration hoist system also includes a platform control system attached to the work platform that is in electrical communication with the motor control system and the hoist motors. Acceleration control is achieved by converting the constant frequency input power to a variable frequency power supply. This may be accomplished through the use of a variable frequency drive(s).