Patent ID: 6870332
Filing Date: 2005-03-22
Classification: H02H,H02P

Abstract:
1. A multi-functional motor control device having connected between three input currents of different phases and a motor; comprising: a main control circuit connected to the there input currents, and including a far end motor actuating control circuit for actuating a motor, a first phase detection circuit for detecting the phase of a pair input of currents selected from the three input currents, a second phase detection circuit for detecting the phase of another pair of input currents, an actuation phase sequence and phase lose detection circuit; and a DC power supply circuit for supplying DC power to the main control circuit; a CPU control circuit connected with the main control circuit and having a CPU; required control values and control functions being set in the CPU control circuit; the CPU control circuit having functions of recording, operation, comparison, receiving input data, output controlling data; a display control circuit being connected to the CPU control circuit and having a microprocessor and connected to an LCD display for displaying control functions and states of the inputs; a function key control circuit connected to the CPU control circuit; the function key control circuit including LED display and including keys for power saving in auto or semi-auto modes; full voltage output; data setting; function setting; auto-start, restart or manual start; fault by-pass; changing display state, etc. so as to set required control functions; a current detection circuit being connected to the CPU control circuit and three current comparators through operation amplifiers, respectively; the current comparators being connected to the currents of a motor of different phases for detecting the currents of the motor to be provided to the CPU control circuit so as to get the values of current variations, phase information of power, controller and motor to know whether any phase is lost, and whether the current is balanced and whether the current is over-loaded; if these conditions exist, then the CPU control circuit will trigger the silicon control trigger circuit to stop the motor according to preset stop conditions so as to avoid the abnormal operation of the motor; a silicon control trigger circuit including a silicon controlled SCR circuit, a feedback current phase detection circuit, and a trigger circuit; the silicon controlled SCR circuit being serially connected between the power source and the motor; the feedback current phase detection circuit serving to detect the phase of feedback current and then transfer detection results to the CPU control circuit; a phase of the feedback current phase being compared with a phase of the voltage of power source for determining the load and for determining the trigger angle of the silicon controlled SCR circuit according to the predetermined conditions so as to trigger and conduct the silicon controlled SCR circuit by the trigger circuit to supply power to the motor; an input voltage detection circuit having an independent power supply circuit, a voltage reduction circuit, a microprocessor, and a photo coupler transistor; the input voltage detection circuit being connected between the L when the CPU control circuit gets the voltage of input currents and the voltage is too high, the silicon controlled SCR circuit will not be triggered and stops the motor so as to protect the motor; when the voltage is too low, the silicon controlled SCR circuit output with a full voltage so as to retain the operation of the motor; when power is actuated, the actuation phase sequence and phase lose detection circuit will determine whether any phase is lost and the result is inputted to the CPU control circuit; if any phase is lost, the CPU control circuit will stop the succeeding operation; at the same time, the phase sequences of the input currents are detected for determining the phases of the three input currents by using the first and second phase detection circuit.