Solution: When variable frequency speed control is adopted for gantry crane, it is recommended that special-purpose motor for variable frequency be used. CHV190 frequency inverter provides close-loop vector control way for supporting, closing and luffing mechanisms, open-loop vector control way for stroking and slewing mechanisms, which ensure supporting, closing and luffing mechanisms do not slip at low speed and full load, stroking and slewing mechanisms start and brake smoothly. For electric brake, it is recommended that commonly used resistor energy consumption brake way be used. For long working stroke for hoisting mechanism of gantry crane, it is recommended that function of light load for speed rise be used, namely, low speed at heavy load and high speed at low load to improve working efficiency of the gantry crane. For synchronous needs of supporting and closing mechanisms in opening and closing of grab and synchronous hoisting, master and slave control is provided to ensure synchronization of speed and power balance.
- It is highly safe, reliable contracting brake and contact control procedures ensure the gantry crane to operate safely and reliably.
- The function of master and slave control and light load for speed rise improves hoisting efficiency of the gantry crane and adapts to traditional operation way of general tower cranes.
- It is more energy saving and debugging is more flexible and highly efficient than speed change with traditional wound rotor motor connecting to a resistor in serial.
- Integrating special-purpose function of several kinds of cranes, it simplifies design and improves on-site debugging efficiency.