Patent classifications
Y02B50/00
Emergency back-up power system for traction elevators
An emergency power supply for a traction elevator system utilizes a microprocessor-based control arrangement with pulse-width modulator technology to create an efficient, cost-effective back-up power system for a traction elevator. The microprocessor-based control arrangement is used to sense a phase irregularity in the power supply. Upon sensing the phase irregularity, the microprocessor-based control arrangement disconnects the elevator system from the main power source and then generates a control signal to initiate the supply of back-up power. Once the elevator electrical system has been stabilized, the elevator control system will sense that recovery has occurred and will then provide an appropriate speed and direction command to the traction motor drive system.
Converter pulse width modulation strategies for three phase regenerative drives
A three-phase regenerative drive employing multiple converter pulse width modulation (PWM) strategies. The drive includes a three-phase converter having inputs for connection to a three-phase AC source, the three-phase converter having three phase legs, a DC bus operably connected to the three-phase converter wherein the three phase converter is configured to direct current from the three-phase AC source to the DC bus, and a three-phase inverter operably connected to the DC bus and a motor, the three phase inverter configured to draw current from the DC bus and provide three phase command signals to the motor. The three-phase converter employs a first PWM strategy to supply current to the DC bus, and the converter employs a second PWM strategy to supply current to the DC bus if a total current in the three phase legs exceeds a selected threshold.
Elevator system having battery and energy storage device
A system for an elevator includes at least one battery and an energy exchanger coupled to the at least one battery and configured to let a DC bus float between a first voltage and a second voltage. An energy storage device is coupled to the energy exchanger. The energy storage device is configured to recapture energy that is not recaptured by the at least one battery during a run of the elevator. The energy storage device is also configured to provide energy to the elevator when demand for energy by the elevator exceeds a threshold.
Energy-saving traction-type elevator
An energy-saving traction-type elevator and an energy-saving method therefor are presented. The traction-type elevator includes at least one counterbalance unit, each counterbalance unit comprising a traction machine. The traction-type elevator further includes an automatic transmission, a hoist-type lifting mechanism, a power-generating electric motor, and a controller provided in a machine room, and a car, a fixed counterweight and a balancing counterbalance provided in an elevator shaft. The energy-saving method applies the principle of moment balance, whereby adding a separate elevator balancing counterbalance to achieve intelligent counterbalancing of the elevator so that the elevator achieves relative balance, thereby reducing the traction moment and rate of work of the traction machine. When the potential energy of the elevator balancing counter-balance builds up to a high position, the power-generating electric motor can perform centralized power generation, aiding in energy recovery and use.
CONVERTER PULSE WIDTH MODULATION STRATEGIES FOR THREE PHASE REGENERATIVE DRIVES
A three-phase regenerative drive employing multiple converter pulse width modulation (PWM) strategies. The drive includes a three-phase converter having inputs for connection to a three-phase AC source, the three-phase converter having three phase legs, a DC bus operably connected to the three-phase converter wherein the three phase converter is configured to direct current from the three-phase AC source to the DC bus, and a three-phase inverter operably connected to the DC bus and a motor, the three phase inverter configured to draw current from the DC bus and provide three phase command signals to the motor. The three-phase converter employs a first PWM strategy to supply current to the DC bus, and the converter employs a second PWM strategy to supply current to the DC bus if a total current in the three phase legs exceeds a selected threshold.
Regenerative electrical power supply for elevators
An energy storage system is provided including: an elevator; an elevator motor; a power system coupled to the elevator motor. The power system including at least one capacitor operable to store energy received form the elevator motor and to supply stored energy to the elevator motor; and at least one flywheel operable to store energy received from the elevator motor and to supply stored energy to the elevator motor.
ELEVATOR
An elevator includes an elevator motor; a motor drive for the elevator motor having a frequency converter including a rectifier bridge, an inverter bridge and a DC link in between, which frequency converter is controlled via a controller, the rectifier bridge being connected to AC mains via three feed lines including chokes, and the rectifier bridge being realised via controllable semiconductor switches; a contactor being located between the feed lines and AC mains; and a backup power supply at least for emergency drive operation. An emergency control is associated with the motor drive, which emergency control is configured to perform an automatic emergency drive. The emergency control is connected to a manual drive circuit having a manual drive switch for a manual rescue drive. The elevator includes a motion sensor connected to the emergency control, whereby the emergency control is configured to activate a brake and/or gripping device of the elevator in case the car speed during a manual rescue drive exceeds a predetermined threshold value.
ELEVATOR
An elevator includes an elevator motor; a motor drive for the elevator motor having a frequency converter comprising a rectifier bridge, an inverter bridge and a DC link in between, which frequency converter is controlled via a controller, the rectifier bridge being connected to AC mains via three feed lines comprising chokes, and the rectifier bridge being realised via controllable semiconductor switches; a contactor being located between the feed lines and AC mains; a backup power supply at least for emergency drive operation; and an emergency control for performing an automatic emergency drive. The backup power supply is via a first switch connectable with only a first of said feed lines. A second and/or third of the feed lines is, via a second switch, connectable as power supply to a car door arrangement, the first switch, as well as the second switch, are controlled by the emergency control, and the emergency control is connected to a manual drive circuit having a manual drive switch for a manual rescue drive.
Elevator
A pressurized fluid powered cabin-management system for an elevator system with a cabin and drive system is provided. The cabin-management system is configured to direct operation of the elevator system upon arrival of one of the cabins at a floor, and comprises a floor detector configured to detect when the cabin is located at a floor and to activate a timer. The timer is configured, when triggered, to activate a timing arrangement and to pass pressurized fluid to a control valve being in a first position. The timing arrangement is configured to direct the control valve to assume a second position after a predetermined amount of time. The cabin-management system performs, when pressurized fluid is passed to the control valve in its first position, actions for opening a door, and, after the control valve has assumed its second position, actions for travel of the cabin.
SINGLE PHASE OPERATION OF THREE PHASE REGENERATIVE DRIVES
A three-phase regenerative drive configured for operation from a single phase alternating current (AC) power source, the three-phase regenerative drive including a three-phase converter having inputs for connection to a single-phase AC source, the three-phase converter having three phase legs, a three-phase inverter for connection to a motor, the three phase inverter configured to provide three phase command signals to the motor, and a DC bus connected between the three-phase converter and the three-phase inverter. A first phase leg of the three-phase converter and a second phase leg of the three-phase converter are employed to direct current from the single-phase AC source to the DC Bus and a third phase leg of the three phase legs of the three-phase converter returns current to a return of the AC source.