Abstract: A control system to realize input power changing along with both loads and rotate speed by an inverter bridge dragging many sets of motors, is composed of a stator voltage regulating unit (1), a motor unit (2), a rotor speed control unit (3), an inverter bridge unit (4), a control drive unit (5) and a signal processing unit (6). By setting a power factor sensor, the phase voltage and phase current of the motor stator are acquired as a control signal to regulate the input power so as to make it change with loads. At the same time, by setting a voltage sensor and a current sensor, motor rotor phase voltage, rectifier output current, overvoltage protection current and chopper working current are acquired separately as a control signal to regulate the input power so as to make it change with the rotate speed, thus realizing input power changing along with both loads and rotate speed.

Abstract: A control system to realize input power changing along with both loads and rotate speed by an inverter bridge dragging many sets of motors, is composed of a stator voltage regulating unit (1), a motor unit (2), a rotor speed control unit (3), an inverter bridge unit (4), a control drive unit (5) and a signal processing unit (6). By setting a power factor sensor, the phase voltage and phase current of the motor stator are acquired as a control signal to regulate the input power so as to make it change with loads. At the same time, by setting a voltage sensor and a current sensor, motor rotor phase voltage, rectifier output current, overvoltage protection current and chopper working current are acquired separately as a control signal to regulate the input power so as to make it change with the rotate speed, thus realizing input power changing along with both loads and rotate speed.

Abstract: A system for realizing rotor variable frequency speed control asynchronously and simultaneously is disclosed. Multiple motors are driven via one inverter, which consists of a motor group, a rectifier group, a chopper group, an isolator group, an amperite group, a power capacitor group, a full-bridge or a half-bridge, a speed feedback voltage detector group, and a current feedback voltage detector group. Using inversion control theory, the voltage outputs by a full or half-bridge inverter are an inverse electromotive force of each functional motor, and each motor operates asynchronously and simultaneously. This system may be used in crane operations. As a crane rises, redundant electricity is fed back to the motor via an inverter; and as the crane lowers, the motor will generate electricity, and the electricity is fed back to the motor via the inverter.

Abstract: The present invention discloses a system for realizing rotor variable frequency speed control asynchronously, which drives a plural of motors via one inverter. This system is consisted of a motor group, a rectifier group, a current limiter group, a chopper group, an isolator group, an active inverter, an A/D converter group, a signal processor group, a current detector group and a voltage detector group. By employing inversion control theory and CPU control technology, a plural of motors are controlled on line, the voltage output by one inverter is used as the additional inverse electromotive force of each motor, and each chopper is effectively turned on and turned off via a PWM signal which is output by each driver, so that four jobs of a crane, lifting, luffing, revolving and walking, can be realized. By the present invention, the circuit is simplified, the size is reduced, the cost is lowered, and the reliability is improved.

Abstract: Disclosed is a system for realizing rotor variable frequency speed control asynchronously and simultaneously by driving multiple motors via one inverter, which consists of a motor group, a rectifier group, a chopper group, an isolator group, an amperite group, a power capacitor group, a full bridge or a half bridge, a speed feedback voltage detector group and a current feedback voltage detector group. By employing inversion control theory, the voltage outputs by a full-bridge inverter or a half-bridge inverter is taken as an additional inverse electromotive force of each functional motor according to the rated power of the motor, and each motor is made to operate asynchronously and simultaneously by the work of each chopper, thereby the operations of a crane, lifting, luffing, revolving and walking, can be realized.