摘要:
A solid state, electric motor control circuit is provided in conjunction with a solid state throttle and vehicle sensor circuit that together incorporate; a Hall Effect throttle position sensor circuit, a throttle position signal amplifier circuit, a vehicle reverse condition circuit, a vehicle operation inhibit circuit, a pulse width modulation circuit, and inverting MOSFET driver circuit, a plurality of power MOSFET devices, a voltage regulator circuit, and a current delivery circuit associated with an external DC electric motor. These circuit elements combine to translate a mechanical throttle position into a voltage level signal that can be converted by pulse width modulation circuitry into a pulsed wave form signal that suitably drives a bank of MOSFET, solid state switches so as to control the flow of current through a DC electric motor. The circuit isolates the DC power source from the power drain components in the circuit and communicates vehicle conditions, such as reverse/forward direction and on/off operation, from the vehicle itself to the power controller circuitry. The circuitry incorporates internal elements that raise reliability while still providing versatility in application. Although the present circuitry involves voltage regulation components, it also utilizes current limiting elements as well as over-voltage protection and significant levels of signal filtering.
摘要:
The pulse width modulated DC motor speed control circuit indirectly senses motor current using sense MOSFETs and a peak detector circuit with storage capacitor for deriving an average motor current signal. The average motor current signal is used both in the feedback loop of the pulse width modulated speed control circuit and also in the motor shutoff or clutch circuit. The clutch circuit shuts off power to the motor when a user-settable torque is reached. The motor speed control circuit is therefore adapted for use in hand-held DC power tools such as screwdrivers and nutdrivers which stop rotation at a predefined torque.
摘要:
Herein disclosed are a method and an apparatus for suppressing a torsional vibration in an electric motor speed control system including a mechanism for transmitting a drive torque from an electric motor to a load through a drive shaft having a torsional spring system. Generally speaking, the signal of a speed detector (3) of an electric motor is a pulsating signal of high frequency. Even if this speed detecting signal is differentiated, it is impossible to obtain a signal proportional to the changing rate of the motor speed. By computing an average value of the signals of the motor speed detector (3) for every predetermined period, however, the pulsating value of the speed signal can be reduced to compute the changing rate of the motor speed from that signal. In the present invention, an acceleration torque command of the electric motor is given in terms of the output signal of a speed controller (11) to cancel the load torque of the electric motor from disturbing the acceleration torque of the motor, with the torque command compensating signal outputted from a motor acceleration torque controller (25) having a proportional gain and an integrator. As a result, the disturbing torque of the electric motor, which is generated by the load and the torsion of the drive shaft during an acceleration and at an abrupt load fluctuating time, is canceled so that the torsional vibration is suppressed to stabilize the variable speed characteristics.
摘要:
A load driving circuit causes a driving current to flow through a load, such as a reel motor, an audio load or the like through the collector and emitter of a drive transistor. A load voltage which changes according to changes in the driving current is obtained at a point of connection between the drive transistor and the load. On the basis of the load voltage, an offset voltage having a predetermined constant value is generated in a power supplying circuit so as to cancel a change in the load voltage. The offset voltage is supplied as driving source output to the drive transistor so as to prevent the generation of excess heat in the drive transistor even if the driving current changes.
摘要:
A motor torque control assembly is provided which can automatically adjust the motor torque so that its reaction torque remains substantially constant, and so that the reaction torque is not changed by changes in motor internal variables, such as bearing drag, current loop tolerances, motor drag, speed change, and temperature change. Such assembly includes a motor subassembly and a feedback subassembly. The motor subassembly has torque input signal means, a summer unit, a compensator unit, a current loop unit, a motor unit, and a torque output means. The feedback subassembly has torque output sensing means connected to the torque output means for measuring the reaction torque value and connected to the summer unit for measuring the difference of the reaction torque value from a motor torque value of the torque input signal means. A digital feedback subassembly has a divider unit for providing angular acceleration of the motor output and a multiplier unit for providing torque from acceleration and connected to the summer unit. Another embodiment of an analog feedback subassembly has an integrator unit and a low pass filter unit connected to a differentiator unit which connects to the summer unit.
摘要:
In a circuit arrangement for the timed control of semiconductor switches (1-4) to each of which a freerunning diode (D1-D4) is connected in parallel and which are arranged in branches of a bridge, an ohmic-inductive load (5) of low loss power which lies in the diagonals of the bridge is to be acted on by a controlled average current value. For this purpose two semiconductor switches (for instance 1, 4) lying diagonally opposite each other in the bridge are closed in a current-application phase while in the following freerunning phase a freerunning current flows through the load. For the reduction of the loss power, at the start of the freerunning phase only one (1) of the two diagonally opposite semiconductors (1,4) is opened and a semiconductor switch (3) which lies in the bridge alongside the conductive semiconductor switch (4) is then closed. Before the start of a current-application phase which follows this, the semiconductor switch (3) which lies in the bridge alongside the closed semiconductor switch (4) is opened before the opened semiconductor switch ( 1) of the two diagonally opposite semiconductor switches (1,4) is closed again.
摘要:
An electromagnetic servo device (200) includes a driving control circuit (100), for an electric motor (20) for producing auxiliary torque to be applied to an output shaft (4). A control signal (Va) is provided to thereby supply an armature current (Io) of a controlled quantity, in a controlled direction of conduction thereof, in accordance with a detection signal (Vr, Vl) from a detection mechanism (13). The detection mechanism detects a phase difference (dP) between an input shaft (1) and the output shaft (4). The rotation speed (N) of the electric motor (20) is controlled with the control signal (Va), and is proportional to the quantity of the phase difference (dP).
摘要:
A torque control apparatus for a compressor driven by a motor through a main shaft, in which variations of the rotation speed of the main shaft due to torque variations are detected at selected angular positions of rotation of the main shaft. Current values to be supplied to the motor for eliminating the rotation speed variations depending on the angular positions of rotation of the main shaft are computed and stored during at least one revolution of the main shaft, and, in the next revolution of the main shaft, that is, when the main shaft rotates then to a 360.degree. advanced angular position, the motor current is controlled on the basis of the current values supplied for at least one revolution of the main shaft, thereby eliminaitng variations of the rotation-speed of the main shaft.
摘要:
To control the intermittent movement of a conveyor belt or carousel, fitted with molds, in a unit for the manufacture of moldings from multi-component plastics, an intended/actual value comparison of the speed of the conveyor belt or carousel as a function of the distance of the molds from fixed devices for filling, demolding and similar operations of the molds is carried out so as to provide control signals for the electric motor. The actual value is determined from a signal voltage generated in correspondence with the rotary movement of the electric motor. The signal voltage is additionally, and in parallel to the speed regulation, converted to electric pulses which are summed in their time sequence, as a function of the movement steps of the conveyor belt or carousel, and are compared with a predetermined master function which can be varied.
摘要:
A well pump control system is disclosed for utilization with a conventional well pump having a stationary member and a reciprocating member. The reciprocating member operates a down-hole pump and is attached to a rocking beam through a load cell. The rocking beam is driven by an electric motor through a counterbalanced crank. The strain present on the reciprocating member as detected by the load cell is utilized to operate a variable frequency drive unit which acts to control the frequency of the voltage applied to the electric motor. In this manner, the speed of the motor may be selectively and gradually varied during the pump cycle to both minimize power consumption and increase slip during heavy loading. Additionally, the maximum amount of strain present on the reciprocating member can be controlled throughout the entire cycle to minimize maintenance costs associated with excessive strain.