Abstract: A method for setting parameters of an ECM motor, the method including: 1) energizing the motor and measuring the AC input voltage Vac; 2) allowing the motor to run according to recorded rotational direction data and rotational speed data when Vac>Vset1; 3) enabling the motor to enter a programming state of rotational direction data and rotational speed data when Vac<Vset2; 4) conducting the programming state including operating the motor in a rotational speed state, a rotational direction state, or a combined state thereof, with each state lasting for a time of T, respectively; and 5) determining that the programming state is proper when the user turns off the power; and storing the programming state in operation at the moment when the power is turned off as normal operating parameter of the motor.
Abstract: A controller for controlling a wiper unit including a wiper and an intermittent wipe cycle setting device for setting an intermittent wipe cycle of the wiper. The cycle setting device is set at a plurality of positions respectively corresponding to different intermittent wipe cycles. Further, the cycle setting device has a resistance value, which changes in accordance with each of the positions, and generates an output signal, which is in accordance with the change in the resistance value. The controller computes position information of the intermittent wipe cycle setting device from the output signal by using a learned value. The computer adjusts the learned value in accordance with the computation result of the position information to correct the position information. Accordingly, resistance value variances of the intermittent wipe cycle setting device are automatically corrected.
Abstract: A traction control system for controlling an electric traction motor drivingly coupled to a wheel of a tractive vehicle. The traction control system includes means for determining speed of the wheel, means for determining tractive effort of the wheel and a control circuitry for controlling drive signals to the motor based upon the wheel speed and tractive effort.
June 30, 2005
Date of Patent:
October 23, 2007
General Electric Company
Jeremy Thomas McGarry, Somakumar Ramachandra-Panicker, Ajith Kuttannair Kumar, Venkatarao Ryali, Bret Dwayne Worden, Jeffrey Louis Daigle, Paul Kenneth Houpt
Abstract: An electrically powered hand tool is described and which includes a three phase electrical motor having a plurality of poles; an electrical motor drive electrically coupled with the three phase electrical motor; and a source of electrical power which is converted to greater than about 208 volts three-phase and which is electrically coupled with the electrical motor drive.
Abstract: A system for variable speed motor control provides continuous variable speed motor controller for each motor or motor application within a family of multi-tap motors while using a single controller. The single controller utilizes a wave chop technique providing variable speed motor control through the operating range for each motor tap and seamlessly passes the motor control to each succeeding tap to provide smoothly varying and continuous variable speed motor control throughout the operating range of the multi-tap motor. The system can use a small wave chop firing angle for each tap, thus maximizing the signal to the motor for each tap and minimizing heat build up in the motor. By selecting the controller to operate on a tap basis, an entire family of motors or motor applications can be accommodated with a single controller and apparatus.
July 26, 2005
Date of Patent:
July 11, 2006
Dennis S. Gambiana, Bradford L. Blankenship
Abstract: An electric drive includes a rotatable shaft, a first drive member, and a second drive member, and is supplied with power from a controller. The controller is operable to supply a first power from a power electronics converter, and a second power that is line power. Supplying the first power individually to the first drive member results in a first shaft speed and first output torque, supplying the second power individually to the second drive member results in a second shaft speed and second output torque, and supplying the first and the second drive members with power at the same time results in a third shaft speed and a third output torque.
Abstract: A rotation speed search apparatus for an induction motor includes: a voltage control unit for comparing a rated current of a motor and a current detected from the motor and generating an output voltage; and a frequency control unit for comparing a reference excitation current of the motor and an excitation current detected from the motor and generating an output frequency. In case of a big load, an output frequency is reduced. Thus, the slip of the motor is moved to a slip where a maximum torque is generated to enable the induction motor to start. If the speed of the motor in operation is greater than a target frequency, an output frequency is increased, so that the motor can be operated even in the regenerative region of the motor.
Abstract: An induction machine includes a rotor having rotor flux and a rotor resistance. The induction machine outputs first and second reference current values. A control system includes a first controller that outputs first and second reference voltage values to the induction machine and that generates an estimated rotor flux magnitude value based on a rotor resistance parameter. A computation circuit receives the first and second reference current values from the induction machine and the first and second voltage reference values from the first controller and calculates an actual rotor flux magnitude. A rotor resistance adjustor that updates the rotor resistance parameter based on the actual and estimated rotor flux magnitudes.
August 6, 2003
Date of Patent:
March 22, 2005
General Motors Corporation
Milan S. Mijalkovic, Aleksandar M. Stankovic, Silva Hiti, James M. Nagashima
Abstract: A method for determining phase current for each of a plurality of individual phase coils of a switched reluctance machine (SRM) is disclosed. In an exemplary embodiment, the method includes determining the current passing through a first resistive element and a second resistive element in an SRM drive circuit. A conduction mode of the SRM drive circuit is determined, the conduction mode being based upon an ON/OFF state of each of a pair of switching transistors controlling current through each of the plurality of individual phase coils. The phase current through each of the plurality of individual phase coils is then calculated, based upon the conduction mode and the determined current passing through said first and second resistive elements.
Abstract: The present invention relates to a system for controlling the rotation speed of AC motors, in particular single phase motors. In this case, a controllable electronic switching device is connected upstream of the motor and is actuated by a control unit such that a sinusoidal input AC voltage is used to produce a motor AC voltage which can be varied in order to change the rotation speed. The control unit is designed in such a manner that the fundamental frequency and/or the amplitude of the motor AC voltage can be varied by phase gating.
Abstract: A rotary induction machine in which operating characteristics of the machine are controlled by adding impedance elements to the rotor windings in which the impedance elements are stationary and connected to the rotor windings by a rotary transformer.
Abstract: A rotary induction machine having wound primary and secondary windings with resistive means connected in series with secondary windings and inductive reactive means connected across said resistive means, with the inductive reactance means and resistive means selected to provide an effective resistance which controls the current in the generator secondary windings, whereby the generator rated current is reached at the highest slip for the range of desired power output.
Abstract: The present invention is related to the method to find the rotor flux angle from stator voltages and currents by injecting high frequency signal. The injected signal is not rotating one but fluctuating one at a reference frame rotating synchronously to the fundamental stator frequency. The difference of impedances between the flux axis and the quadrature axis at high frequency signal injected on the rotor flux angle is explained by the equivalent circuit equation of the induction machine. The difference is verified by experiments on the test motors at various conditions. The sensorless field orientation control method is proposed and experimental results clarify the satisfactory operation of the method with 150% load torque at zero stator frequency.
Abstract: An alternating current induction motor having a multitapped RUN winding and including a controller which automatically determines an instant tap selection in response to changes in applied a.c. electric power voltage level appearing immediately at the motor terminals. A measure of instant level of the motor terminal voltage is utilized to automatically reselect the RUN winding tap selection in order to maintain a near constant level of magnetic excitation in the stator field irrespective of immediate changes or variations in the available motor terminal voltage. Electric lawn mowers, power tool motors and other heavily loaded motors which may normally be operated at the end of various lengths of especially long and lossy extension cords or the like may advantageously utilize my control technique to maintain operation with an about normal and constant level of power, independent from usual performance degrading voltage drop losses commonly encountered in the extension cord.
Abstract: A rotary induction machine having wound primary and secondary windings with capacitive means connected directly across said secondary windings and resistive means connected in series with said secondary windings.
Abstract: There is disclosed a method of controlling an induction motor, which controls a primary current of the induction motor on the basis of a magnetic flux component current command i.sub.1d *, a torque component current command i.sub.1q *, and a slip frequency command .omega..sub.s which are orthogonal component command values of the primary current of the induction motor, wherein control parameters R.sub.2 *, l.sub.2 * and M* set in accordance with a secondary resistance R.sub.2, a secondary leakage inductance l.sub.2 and a mutual inductance M of the induction motor are used to calculate the magnetic flux component current command i.sub.1d *, the torque component current command i.sub.1q * and the slip frequency command .omega..sub.s. Even in the case where the mutual inductance M of the induction motor varies, if the coefficient 1/M* is assumed as a magnetic saturation function given by a gap magnetic flux, the influence of the magnetic saturation can be canceled.
Abstract: A motor drive control apparatus having an electrical power amplifier for supplying an electrical power to a motor, and a current control loop and speed control loop for controlling the drive of the motor, which includes a current feedforward component calculation section for creating voltage commands to be imposed on respective phases from current commands for the respective phases for the motor and the impedance model of the motor for carrying out a feedforward control by using the voltage commands to be imposed on the respective phases.
Abstract: A control system for controlling the load of an AC motor/generator of secondary AC excitation type connected to a power system in parallel to at least a synchronous machine. The AC motor/generator has the secondary excitation winding thereof controlled in the amount of excitation so as to generate an output in accordance with an external output command. In the case of variation of power flow between the power system and the synchronous machine, the output command is corrected in accordance with the variation, and the amount of the secondary excitation is controlled by the corrected output command, whereby the variation of power flow between the power system and the synchronous machine is absorbed by the AC motor/generator thereby to prevent the synchronous machine from stepping out.
Abstract: The present invention provides a method for starting motors by harmonics for synchronous motors, wound-rotor and cage-rotor asynchronous motors started thereby. During the starting period, according to the present invention, the connection of the stator winding is changed so as to create some very strong harmonic fields. The harmonic fields are associated with the rotor windings and are used to improve the starting performance of the motor. The three motors all have large starting torque, small starting current and can be started by direct-on-line. The wound-rotor asynchronous motor has no brushes or, slip rings on the rotor and there is no electric contact thereby increasing the reliablity of starting and running. The running efficiency is superior to the cage-rotor asynchronous motor.
Abstract: A control for a wound rotor induction motor including shorting switches in a secondary resistance network comprises an input comparator with voltage limiting switched by the rotor voltage, a pulse generator responsive to the input comparator to generate voltage pulses of predetermined constant duration at a frequency proportional to the frequency of the rectangular voltage wave, a low pass filter effective to filter the output of the pulse generator to a DC voltage inversely related to rotor speed, a DC power supply effective to generate a plurality of DC reference voltages, a plurality of switch control comparators, each receiving the output of the low pass filter on one input and one of the DC reference voltages on the other input and a plurality of switch actuators, each switch actuator being responsive to the output of one of the switch control comparators to activate a group of shorting switches at a predetermined rotor speed during motor acceleration and deceleration.
Abstract: A squirrel-cage induction motor comprises a stator having a stator core and stator windings divided into first and second coils with different numbers of poles, and a squirrel-cage rotor including a rotor core and a plurality of rotor conductors embedded in the vicinity of the surface of the core. The number of the rotor conductors is the same as the average number of poles of the first and second stator coils, which conductors are arranged equidistantly along the periphery. This induction motor, with the construction of a squirrel-cage rotor, permits a variable speed operation without using any special device.
Abstract: A variable speed induction motor includes a photo-electric cell which controls the current delivered the rotor induction coils. The control is effectuated by the use of controlled diodes, the control electrodes of which are electrically connected to the photo-electric cell. The resistance of the photo-electric cell can be varied by an external, operator-controlled light source. Thus, the speed of the motor, which is proportional to the current in the induction coils, is controlled by the operator through the use of the light source.
Abstract: A method of controlling the speed of an induction motor comprises the steps of feeding a supply voltage to the winding of a motor stator and obtaining a signal proportional to the motor speed by varying the voltage across the winding of a motor rotor before activating switch thyristors in the rotor circuit. When the obtained signal exceeds a predetermined value, a signal enabling the switch thyristors will be shaped using the same signal. After one of the thyristors is activated, the level of the voltage measured across the rotor winding is reduced to zero or to a value below a predetermined value, thereby causing the signal to cease. Then the entire process is repeated for each of the subsequent thyristors. The speed of several motors may be controlled.
March 16, 1981
Date of Patent:
April 17, 1984
Vladimir S. Boev, Sergei P. Golev, Viktor I. Dmitriev, Efim M. Pevzner, Andrei G. Yaure, Lev B. Masandilov
Abstract: The control system has application to polyphase AC wound rotor motor which employ opposed parallel connected phase controlled thyristors together with series connected fixed resistors in each leg of a delta connected secondary impedance network. The line-to-line secondary terminals of the motor provide a source of polyphase variable frequency and variable amplitude AC reference signals. The variable frequency, variable voltage reference signals are converted into complementary pairs of square wave synchronization voltages. These same reference voltages are also concurrently integrated during their respective positive and negative half cycles to provide complementary pairs of constant peak amplitude, variable frequency voltages which are combined with associated ones of the aforementioned synchronization voltages to provide synchronization locks.