Method for controlling three-phased asynchronous electric motor of down-pump and system for controlling electric motor of down-pump
FIELD: electric engineering, possible use for controlling three-phased asynchronous electric motors of down-pumps, used mainly for oil extraction.
SUBSTANCE: in the method for controlling the three-phased asynchronous electric motor of down- pump and in the system for controlling electric motor of down-pump in case of failure of frequency regulator or jamming of electric motor rotor, by means of mode switch, mode of direct launch from electric network is set. In that mode transfer of electric energy to electric motor occurs via chain: three-phased electric network - increasing voltage transformer - three-phased asynchronous electric motor. The control system contains a frequency control circuit and direct launch circuit, first key, connected to frequency controller and controlling feeding of power to it; input and output filters, second key, by means of which control modes are switched, third key, controlled by controller, and transformer which increased power voltage of electric motor.
EFFECT: increased efficiency.
2 cl, 4 dwg
The invention relates to the control of three-phase asynchronous motors, submersible pumps, used mainly for oil production.
Widely used method of controlling three-phase asynchronous motors of submersible pumps, which consists in the control of three phase induction motor using a frequency regulator and to adjust the frequency of rotation of the rotor of the electric motor.
Describes how the control is implemented in the control station three-phase asynchronous motor series "electon-05" (see figure 1, 2 manufacturer JSC "election", Raduzhny, Vladimir region, CTCD 065 ES)containing the frequency controller and the control system. Frequency control allows you to adjust the rotational speed of the rotor of the electric motor. The control system allows you to set the operating modes and to control the operation of the frequency controller.
The closest analogue shown in figure 2, contains the input terminals of the water management system for the connection of three-phase electrical network, an automatic switch For controlling power to a frequency regulator of the Czech Republic and provides short circuit protection in the circuit of the Czech Republic. Included in the scheme, the controller Contr provides control of the frequency controller of the Czech Republic, as well as the control parameters such as voltage requirements the phase of the electrical network Uc and current of the power circuit frequency regulator. The controller Contr is designed for user interaction; output terminals Wyhk designed to connect a device with a step-up transformer and forth with three-phase asynchronous motor.
The disadvantage of the described method and device for its implementation is the inability to control motor failure frequency regulator or cannot run the motor using a frequency regulator, for example, when jamming of the rotor of the electric motor.
The purpose of the proposed technical solution is the ability to control three-phase asynchronous motor with frequency regulator or directly from the mains with saving control failure frequency regulator, or inability to run the motor using a frequency regulator, while the ease of implementation of this method in the device.
This goal is achieved by the introduction of additional control mode motor - direct start-up mode, directly from the electrical network.
In the device described mode is implemented by including additional circuit direct start-up, consisting of conductors that transmit electricity passing frequency, R is gulator and the mode switch to control three-phase asynchronous motor, which is set to either the control mode using a frequency regulator, or the direct start-up mode.
The method of control of an induction motor is illustrated in figure 3. In normal operation, when the switch control modes set the mode control motor using a frequency regulator. In this mode, the transmission of electricity to the electric motor is in circuit: three-phase electric network frequency controller 1, the step-up transformer voltage 2, three-phase asynchronous motor 3. When the emergency mode, for example, failure frequency regulator 1 or jamming of the rotor of the electric motor 3, by means of the mode switch control 4 set the mode of direct start-up from the mains. In this mode, the transmission of electricity to the electric motor is bypassing the frequency regulator circuit: three-phase electric network, which increases the voltage transformer 2, three-phase asynchronous motor 3.
The device for implementing the above-described method of controlling three-phase asynchronous electric motor control electric motor submersible pumps is illustrated in Figure 4.
The device has an input terminal 5 for connection of three-phase electrical network, the key 6, control is shining applying power to the frequency regulator 1; input filter 7, which serves to reduce the influence of the frequency regulator 1 on three-phase electrical network; an output filter 8 serves to protect three-phase induction motor 3 against high voltage surges that occur during operation of the frequency controller; circuit switch - key 4 which is used for switching control of three-phase asynchronous motor; key 9 controlled by the controller 10 and is designed to turn off the motor in case of emergency; output terminals 11, for connecting the device with a step-up transformer 2, designed to improve the electric motor voltage up to 2.5 kV, and then with three-phase asynchronous motor.
The device operates as follows.
In normal mode the switch 4 is set to "Frequency regulation", when this occurs, the circuit of the key 6. In this mode, the control motor is a frequency regulator. The controller sets the operation mode of the frequency controller controls the electric parameters - voltage three-phase electric network (Uc) and through current sensors current consumption of the motor (Ia), and manages the key 9.
Failure frequency regulator or cannot run the electric motor is El through the frequency control of the key 4 is set to "Direct start", when this occurs, the opening of the key 6 and the stop of the power supply frequency regulator. In this mode, the controller controls the electric parameters - voltage electrical network (Uc) and the current consumption of the motor (Ia), and also controls key 9.
1. The method of controlling three-phase asynchronous motor of a submersible pump, comprising a speed control of the motor in normal operation of the frequency controller, wherein when the emergency mode by the mode switch control set position "direct start", turn off the power supply frequency regulator and set the mode to direct starting of three-phase asynchronous electric motor from the electric network.
2. The control system of the motor of a submersible pump that contains the frequency controller, the key that controls the voltage supply to the frequency control of three-phase electric network, the step-up transformer supply voltage three-phase asynchronous electric motor, characterized in that the input key for switching control of three-phase asynchronous motor, which is in the normal mode of operation provides for the transmission of electricity through the circuit: three-phase electric network frequency controller that increases Transfo is motor voltage, three-phase asynchronous electric motor, and in emergency mode - in chains: three-phase electric network, the step-up transformer voltage, three-phase asynchronous motor, the controller for opening the key that controls the power to the frequency controller, and disconnect the three-phase asynchronous motor in emergency mode by key, designed to turn off the motor.
FIELD: electric engineering, possible use in autonomous electric supply systems of spacecrafts for supplying power to consumers from limited power supply, such as a solar battery.
SUBSTANCE: in accordance to the invention, constant voltage regulator contains input and output clamps for connecting power supply and load, metal-dielectric-semiconductor transistor, connected in parallel to output clamps, and dividing Schottky diode, installed between same name poles of input and output clamps. Second metal-dielectric-semiconductor transistor with control driver is introduced serially with dividing Schottky diode. Threshold device is introduced additionally, input of which is connected in parallel to dividing Schottky diode, and output - to controlled input of control driver.
EFFECT: increased reliability of operation of charge-discharge device due to ensured protection of power supply circuits and accumulator battery from short circuits in separate cells.
FIELD: automatic control systems for protecting high voltage adjustable rectifiers for powering gas cleaning filters in various industrial branches and in agriculture.
SUBSTANCE: on disruption of thyristors in ac to method, phase of load current impulse front φ is measured as well as thyristor key impulse front phase α, their difference is calculated and, when φ-α is greater than zero, signal is dispatched for disabling automatic switch in powering circuit of rectifier or value of duration of load current impulse T and duration of impulse of phase-shifting device generating impulses for controlling thyristor key t, are measured, value of their difference is computed and, if T-t is greater than zero, signal is formed for disabling automatic switch in power circuit of rectifier.
EFFECT: increased efficiency.
2 cl, 1 dwg
FIELD: protection of miscellaneous high-voltage converters.
SUBSTANCE: proposed high-voltage unit has two antiphase arms (one phase) of three-phase bridge converter (rectifier or inverter); used as semiconductor devices are power thyristors or diodes; newly introduced in checkup device are second measuring element and second pulse generator; primary windings of checkup device transformers in first and second antiphase arms of high-voltage unit are connected through respective measuring element to output of first pulse generator whose control input is connected to output of second pulse generator.
EFFECT: simplified design, enhanced economic efficiency of checkup device.
1 cl, 2 dwg
FIELD: phase-failure protection of three-phase loads.
SUBSTANCE: proposed control device for three-phase switch built around triacs connected to supply mains phase leads has diode group assembled of two diodes integrated by cathodes and thyristor, all connected through anodes to output terminals of switch, thyristor gate electrode being connected to control unit built around optocoupler whose photothyristor is connected through first limiting resistor to thyristor anode and light-emitting diode anode is connected through anode to cathodes of diode group and its cathode, to neutral bus through variable resistor and second limiting resistor; first and second control buttons; three phase optocouplers whose photothyristors are connected through respective limiting resistors to bridge amplifier output and input is designed for connecting to control junction of respective triac; light-emitting diodes of phase optocouplers are cumulatively interconnected in series, shorted out by second control button, and connected through anode of first light-emitting diode to cathodes of diode group and to first lead of first trigger control button connected by its second lead to cathode of diode whose anode is connected to one of supply mains phase leads, and cathode of third light-emitting diode is connected through load resistor to neutral bus.
EFFECT: reduced heat loss, enhanced reliability of device.
1 cl, 1 dwg
FIELD: integrated circuit protective circuits including those of potential type.
SUBSTANCE: proposed circuit designed for protecting switching transistor that controls electromagnet or valve in control unit of motor-car forced idle run economizer upon occurrence of short circuit through common bus or reduction of load resistance below definite value has ten resistors 2, 3, 5, 9, 23, 26, 27, 32 - 34, seven transistors 1, 4, 10, 13, 22, 28, 30, two electronic switches 19, 29, two current supplies 7, 24, one reference voltage supply 31, one dynamic D flip-flop 1`1, one multiplexer 14, two delay circuits 16, 20, two matching units 18, 21, one regulated voltage supply 25, one power supply 6, thee input buses 12, 15, and 17 for passing initial setting signal, input signal, and clock pulses, respectively, and one output bus 8.
EFFECT: reduced number of leads in protective circuit of integrated type; ability of controlling its on-operation delay time.
1 cl, 1 dwg
FIELD: submersible telemetering systems for oil-extraction pump plants.
SUBSTANCE: proposed device has choke 1 and capacitor 2 forming LC filter 3, as well as reed relay 4 that functions to open circuit on occurrence of overvoltage across device input, its first lead being connected to anode of diode 5 and to first lead of high-rating resistor 6, and its second lead, to series-connected choke 1 of LC filter and to reed-relay keep-alive coil 7. Cathode of diode 5 is connected to first lead of charging resistor 8 whose second lead is connected to first lead of reed-relay making coil 9 and to first lead of storage capacitor 10 whose second lead is connected to common wire. Second lead of high-rating resistor 6 is connected to control lead of electronic switch 11 and to first lead of time-setting capacitor 12 whose second lead is connected to common wire. Second lead of reed-relay making coil 9 is connected to input of electronic switch 11 whose output is connected to common wire.
EFFECT: enhanced reliability of protective gear, reduced size of submersible telemetering equipment unit.
1 cl, 1 dwg
FIELD: electrical engineering; induction motor protection against emergency operating conditions.
SUBSTANCE: proposed method for induction motor protection against emergency operation includes checkup of following two quantities: difference between measurement results of motor input power and measured power output corresponding to that found by calculations, as well as ratio of actual maximal electromagnetic torque that can be developed by motor to mechanical torque on motor shaft. Quantities under check are found including parameters of electrical energy for particular time moment.
EFFECT: enhanced reliability and improved checkup quality of motor protective gear.
1 cl, 2 dwg
FIELD: electrical engineering.
SUBSTANCE: proposed device that has resistor-capacitor reverse-sequence voltage filter, three-phase power supply, two current transformers, two reed relays, rectifier bridge, storage capacitor with discharge resistor, capacitor, final element, phase-meter, two different-structure bipolar transistors, and two optocouplers is provided with newly introduced push-buttons inserted in reverse-sequence voltage filter arms and connected in parallel with one of resistors.
EFFECT: enhanced reliability of three-phase motor protection against unbalanced operation.
1 cl, 2 dwg
FIELD: protection of induction motor stator winding against turn-to-turn fault.
SUBSTANCE: proposed method includes measurements of instant current and voltage across motor terminals, their conversion into voltages proportional to current and voltage, measurement of motor slip, recording of obtained signals proportional to current and voltage which are used to evaluate initial phase of transient and initial current, calculation of next instant currents at initial values of equivalent active resistance and equivalent inductance of motor, comparison of calculated instant currents with respective recorded values, evaluation of their difference, and variation of equivalent active resistance and equivalent inductance depending on this difference until difference between recorded and calculated values of instant current is brought to minimum, comparison of equivalent active resistance and equivalent inductance obtained in the process at measured slip with admissible values, and generation of OFF-operation signal in case these values exceed admissible ones.
EFFECT: enhanced protective-gear selectivity and speed of response.
3 cl, 8 dwg
FIELD: technology for protecting electric machines, in particular, three-phased synchronous generators, from coil short circuits of stator winding and from failures of bearings.
SUBSTANCE: protective device has vibration sensor mounted on the body of electric machine, connected to input of protective device, consisting of serially connected block for comparing vibration amplitude to standard value, amplifier and executive mechanism, while executive mechanism of protective device is included in power chain of electromagnetic drive for protective disabling of switch and excitation device.
EFFECT: increased reliability and sensitivity of protective device while simplifying its construction.
FIELD: electric engineering, possible use for protecting three-phased asynchronous electric engines from non full phase modes and overloads.
SUBSTANCE: device contains asymmetry indicator for voltages of powering network, first, second and third threshold blocks, signals delay block, supporting voltage block, executing block, first and second current transformers, current sensor for asymmetry of phase currents of electric motor, while for excluding galvanic connection of device and electric network, introduced additionally are: diode optic couple into sensor of asymmetry of feeding network voltages, and into support voltage block - separating transformer. To detect reason of disabling of electric motor introduced additionally is fourth threshold block, which depending on abnormal mode of operation of network or electric motor sends positive impulse to light diodes, indicating reason of disabling of electric motor.
EFFECT: increased reliability and expanded functional capabilities.
FIELD: electrical engineering, in particular, microprocessor protection of electrical plants providing for pump operation, applicable for functional check of immersion pump electric motors.
SUBSTANCE: the claimed device additionally uses a microcontroller and load resistors for periodic connection to the supply line with the aid of the contact of another relay.
EFFECT: enhanced reliability of protection of the immersion pump electric motor.
2 cl, 4 dwg
FIELD: electrical engineering.
SUBSTANCE: proposed protective gear designed for overcurrent and overtemperature protection of electric motors and also for preventing ground insulation worsening due to inadmissible reduction of its resistance has overcurrent protection channel, overtemperature protection channel, and ground fault protection channel. These channels are interconnected in parallel and connected through OR gate to final relay whose output is connected to control circuit contacts of magnetic stator whose power contacts are designed to insert motor phases in line. OR gate, final relay, and magnetic stator constitute actuating device of motor protective gear. Differential current transformer is connected to power phase leads in line section between current transformers and motor.
EFFECT: enhanced reliability and reduced installation and maintenance charges of protective gear.
1 cl, 7 dwg
FIELD: electrical engineering; controlling washing-machine motor.
SUBSTANCE: proposed device for controlling washing-machine motor has speed transducer for measuring motor speed and controller that functions to compare measured speed with desired value to evaluate motor input power. Rate of motor turn-on operations is adjusted in compliance with comparison results. Motor power output is evaluated basing on its speed. Rate of motor turn-on operations is reduced in case evaluated power output is too high.
EFFECT: ability of preventing temperature rise of motor and direct-to-alternate current converter to emergency level.
10 cl, 3 dwg
FIELD: electrical engineering.
SUBSTANCE: the device has a power unit, relay coil with a make contact connected to the control circuit by a motor contactor, voltage stabilization unit built around high- and low-voltage stabilizer diodes, temperature protective unit with three transistors and temperature-sensitive resistors built in the stator winding of the electric motor, voltage asymmetry protective unit, transducer of power mains asymmetry voltage, actuator with a transistor, protective unit against emergency braking with an operational amplifier and a transistor, warming unit, the protective unit against emergency braking has resistance strain gauges installed on the components of electric motor fastening to the base and resistors connected to the resistance strain gauges according to the four-arm bridge circuit, whose input is connected to the low-voltage stabilizer diode, and the output is connected to the input of the operational amplifier of the protective unit against emergency braking in parallel with a capacitor, the input of the operational amplifier via an additional resistor is connected to the base of the transistor of the protective unit against emergency braking.
EFFECT: enhanced efficiency of protection of a three-phase synchronous motor and expanded functional potentialities of the protective device.