What is the pump lift voltage? And how to suppress the pumping voltage rise?
[pump voltage] when braking, in the motor winding series resistance, motor equivalent to the generator, the energy will be converted to electric energy consumption in the series resistance. This method is widely used in all kinds of motor braking, and frequency conversion control is also used. From high to low (zero speed), then the electrical frequency changes quickly, but the rotor of the motor with the load (production machinery) mechanical inertia, could not stop quickly, resulting in the back EMF (EU voltage) motor is in the state of power,
The reverse voltage and torque electric torque instead, and the motor has strong braking torque, forcing the rotor quickly stopped, but usually AC-DC-AC converter is the main power AC/DC rectifier circuit is irreversible, and therefore can not return to the power grid, resulting in the main circuit of the capacitor voltage increases two that is called the pump voltage.
The elevator is mainly used by the power grid through the rectifier, filter, inverter and other transmission to the motor. The motor in high speed when the brake suddenly, but the rotor of the motor with the load (production machinery) mechanical inertia, could not stop quickly, resulting in the back EMF (EU voltage) motor is in the state of power, the reverse voltage and torque original electric state torque instead, and the motor with brake strong torque, forcing the rotor to stop fast but usually AC-DC-AC converter is the main power AC/DC rectifier circuit is irreversible and therefore cannot go back to the grid, energy will be accumulated in the filter capacitor, produce pump voltage, this phenomenon of pump voltage converter has great destructive power.
[suppression of pumping voltage] the general use of the installation of absorption resistance to absorb the pump voltage rise. The simplest way to control the pump voltage is to connect the DC bus with an energy consumption resistor before releasing the pump voltage.
