48 results about "Five phase induction motor" patented technology

A method and apparatus are described for controlling the flow of power in each input line to a three phase AC inductive load in order to reduce the amount of VAR in the system, and thus increase the operational efficiency of the inductive load. Solid state relays are positioned in series in each of the three inductive load line inputs, and current allowed to flow to the inductive load only during the time during which the SSRs are in a conducting state. The calculation of VAR is achieved by processing data from each of the input lines using a separate controller boards each dedicated to each of the lines. The controller in turn, based on the calculated VAR, increments the time, either increasing or decreasing it from a predetermined value, during which the SSRs in that line remains in the non-conducting state.

A vector-controlled, dual inverter system for a three-phase induction motor is disclosed. The inverter system comprises a first inverter system which is connected to one end of three phase windings of a stator and performs compensation of a back electromotive force; and a second inverter system which is connected to the other end of the three windings of the stator and performs reactive power compensation.

A driving apparatus of a three-phase induction motor includes: a three-phase power supply unit for supplying three-phase power; a rectifier for rectifying the three phase voltage supplied from the three phase power supply unit; a voltage reducing unit for reducing a DC voltage generated from the rectifier and outputting a stabilized DC voltage; and an inverter unit for varying the DC voltage outputted from the voltage reducing unit to a three-phase AC voltage and driving a three-phase induction motor. A power-factor degradation generated during supplying a DC voltage to the inverter to drive the three-phase induction motor is prevented, a harmonic wave is removed, and because a high-priced inverter component is not necessary, its relevant expense is reduced.

A vector-controlled, dual inverter system for a three-phase induction motor is disclosed. The inverter system comprises a first inverter system which is connected to one end of three phase windings of a stator and performs compensation of a back electromotive force; and a second inverter system which is connected to the other end of the three windings of the stator and performs reactive power compensation.

The invention discloses a system and method for controlling an indirect torque of a single regulating loop of a three-phase induction motor and relates to the technical field of motor drive and alternated current speed regulation. The system is provided with an indirect torque controller, a 32-bit digital signal processor used as the core of the system and a corresponding peripheral circuit. The software of the system comprises a flux linkage observation and torque calculation unit, a steady slip calculation unit, a revolving speed sampling period integral unit, a torque regulator unit, a stator flux linkage vector amplitude and phase calculation unit and a space voltage vector calculating and outputting unit. Through the method provided by the invention, the space voltage vector of controlling the motor in the next period can be acquired by utilizing the efficient value formula of each-phase electromotive force of a motor stator (UE is equal to 4.44kfNF), namely the ratio of the voltage vector amplitude to the phase gain is maintained as a constant when the motion track of a stator flux linkage vector is a flux linkage circle. In the invention, only the torque single proportional-integral (PI) regulating loop is required, thus the system structure is simplified, the dynamic property of the system is enhanced, and the high-performance control of the driving system of the three-phase induction motor is realized.

There are provided a smoothing capacitor (71) for storing an induced electromotive force generated by a three-phase induction motor (5), a regenerative transistor (81 to 86) for switching a terminal voltage of the smoothing capacitor to carry out a power regenerating operation over a three-phase AC power supply (3), a line voltage detecting portion (6) for detecting a line voltage of the three-phase AC power supply, a fundamental waveform generating portion (10) for generating, from a signal output from the line voltage detecting portion, a fundamental waveform defined to be a line voltage waveform of the three-phase AC power supply in which a source voltage distortion component is not mixed, a base driving signal creating portion (7) for creating a base driving signal to be used for an ON / OFF control of the regenerative transistor based on a signal output from the fundamental waveform generating portion, and a base driving signal output portion (9) for outputting the base driving signal.

The invention relates to a three-winding parallel single-phase induction motor. A stator winding of the single-phase induction motor adopts a three-winding parallel connection mode, so when the single-phase induction motor operates under a rated load, the single-phase induction motor has an approximately symmetrical air gap field, has the efficiency closer to that of a same-capacity three-phase induction motor and higher power factor and is small in volume and light in weight. The single-phase induction motor comprises a shell, wherein a stator is arranged inside the shell; a rotor is arranged on a rotating shaft; the stator winding is divided into three phases A, B and C which spatially form an angle of 120 degrees respectively in turn; the phase B and the phase C are respectively connected in series with a respective capacitor; and the phase A is connected in parallel with the phase C and is reversely connected in parallel with the phase B to form a composite parallel branch so as to be connected to a single-phase power supply.

The invention provides a three-phase induction motor star-delta starting control method and device. The device comprises a current and voltage detection unit, a single-chip microcomputer control unit, a human-computer interaction unit, a delta connection switching device based on a solid-state relay and an AC contactor, a star connection switching device based on the solid-state relay, a main circuit AC contactor and a thermal relay device. The current and voltage detection unit is connected on a bus and used for detecting power current and power voltage signals in real time so as to act as the basis of trigger control of the single-chip microcomputer control unit. The single-chip microcomputer control unit is connected with the current and voltage detection unit. The human-computer interaction unit is connected with the single-chip microcomputer control unit. Starting current of the starting instant of star connection can be effectively suppressed so that the current impact of star-delta switching can be reduced, the electromagnetic interference caused by disconnection of a stator winding in the star-to-delta process can also be reduced and thus noise and vibration of starting of an asynchronous motor can be greatly reduced.

The present invention provides a stator, a three-phase induction motor and a compressor. The stator is applied to a three-phase induction motor of a compressor. The stator includes: a stator iron core; a plurality of stator teeth extending inwards along a radial direction of the stator; stator slots distributed between the plurality of stator teeth; and three phases of windings wound around the stator teeth to generate a rotating magnetic field, where a coil of each phase of winding in the three phases of windings is made of a composite wire. The composite wire includes a wire core made of a first conductive metal material, and an outer layer wrapping an outer circumferential surface of the wire core and made of a second conductive metal material, wherein the first conductive metal material and the second conductive metal material have different electrical conductivities.

The present invention relates to an energy-saving system for three-phase induction motors and is based on the principle of variable voltage control at constant speed. It is composed of a microprocessor, exampling circuit, sensing circuit, acquiring circuit, firing circuit, and AC to AC converter. The system is to automatically adjust the voltage to the induction motor with the variation in the motor load, in order to obtain high operating power factor and efficiency. The system will result in considerable energy-savings when a three-phase induction motor runs under constant light-load or variable-load with low duty ratio.

The invention discloses an instantaneous power detection and load identification based induction motor cooperative control system which realizes energy-saving control on a light-loaded or unloaded three-phase induction motor and mainly comprises an instantaneous power detection and load identification cooperative controller using a digital signal processor TMS320F28346 as a core, a three-phase bridge power amplifier, a three-phase bridge driving circuit, the three-phase induction motor, a three-phase diode rectifier bridge, an instantaneous power detection link, a current detection link, a coder rotating speed detection link, a load identification link, a +24V switch power source, a +15V switch power source, a + / -12V switch power source, a +5V power source and the like. An instantaneous power detection and load identification based induction motor cooperative control method is adopted to control stator exciting current of the light-loaded or unloaded three-phase induction motor, and power factors of the three-phase induction motor are adjusted by load rate obtained on the basis of load identification, so that operating efficiency of the three-phase induction motor is effectively improved, and good electricity-saving effect is achieved.

The invention discloses a control method for a double-frequency stator double-winding five-phase induction generation system. The method comprises the following steps: collecting line voltage and phase current of a dual stator winding five-phase induction motor, first direct current voltage of a control winding side and second direct current voltage of a power winding side; respectively converting the line voltage and the phase current into a two-phase static coordinate system; calculating given current of a first frequency and the given current of a second frequency; calculating a phase signal of the first frequency, and converting the given current of the first frequency and the given current of the second frequency into a four-phase static coordinate system from a four-phase rotating coordinate system; and calculating given voltage in the static coordinate system and outputting a pulse width modulation voltage signal. According to the control method, control on optimal output of double-frequency signals and energy of the generation system under double frequencies can be achieved from the perspective of a control strategy on the basis of not changing generator hardware. The invention further discloses a control system for the double-frequency stator double-winding five-phase induction generation system.

Techniques for monitoring the health of a three-phase induction motor are provided. An expected threshold value is calculated as a function of an expected ratio of current unbalance to voltage unbalance for the three-phase motor. Embodiments determine whether a measured current unbalance exceeds the expected threshold value. Responsive to the measured current unbalance exceeding the expected threshold value, a remedial action may be taken, such as generating diagnostic information or activating one or more protection operations for the three-phase induction motor.

The present invention is a three phase induction motor and its speed regulating method which is called modified line phase shift speed regulating method. The three phase induction motor consists of astator and a rotor, of which there is a fixing phase winding with fixed phase shaft and a moving phase winding with movable phase shaft on stator. Each of these two winding will produce a rotary magnetic field and these two rotary magnetic fields having space phase difference will produce two induction potentials having time phase difference accordingly. To move phase shaft of woving phase winding by changing outlet line of moving phase winding to change space phase difference between two rotary magnetic fields and further to change time phase difference between two induction potentials in rotor guide strip, hence the current and composite induction potential in rotor guide strip will be changed and accordingly the rotor rotating speed and electromagnetic torque of three phase induction motor will be change too. The speed can be regulated in multistaze with no harmonic wave pollution.

The present invention provides an electronic braking system for an irrigation machine. According to an exemplary preferred embodiment, the present invention includes a drive controller which includes a power supplying circuit which signals an ON condition when a motive power request is input into the drive controller and an OFF condition when motive power is not input into the system. According to a further preferred embodiment, the present invention further includes a 3-phase induction motor connected to apply torque to a drive shaft which is connected to a least one drive wheel. According to a further preferred embodiment, the power supplying circuit supplies 480V AC of motive power to the drive motor when the drive controller signals the ON condition and 10-80V DC of non-motive power to at least one phase of the motor when the drive controller signals the OFF condition. According to a further preferred embodiment, the application of the DC current is applied immediately after the motive power is removed from the drive motor and the application of non-motive power brakes and prevents the drive shaft from turning until the DC current is removed.

A direct power control system of a high power factor induction motor realizes energy-saving control of a three-phase induction motor under the condition of light load or no load. The direct power control system of the high power factor induction motor comprises a controller using a digital signal processor TMS320F2808 as the core, a three-phase bridge power amplification device, a three-phase bridge driving circuit, the three-phase induction motor, a three-phase diode rectifier, a power factor detecting link, a current detecting link, an encoder rotating speed detecting link, a power factor measuring link, a + 24V switching power supply, a +15V switching power, a + / - switching power supply, a +5V switching power and the like. By means of the direct power control system applying power factor measurement, the stator flux linkage amplitude of the three-phase induction motor under the condition of light load or no load is controlled, instantaneous reactive power of the motor is adjusted, and therefore the motor power factor is effectively improved and a good energy-saving effect is achieved.

The invention discloses a system and method for controlling an indirect torque of a single regulating loop of a three-phase induction motor and relates to the technical field of motor drive and alternated current speed regulation. The system is provided with an indirect torque controller, a 32-bit digital signal processor used as the core of the system and a corresponding peripheral circuit. The software of the system comprises a flux linkage observation and torque calculation unit, a steady slip calculation unit, a revolving speed sampling period integral unit, a torque regulator unit, a stator flux linkage vector amplitude and phase calculation unit and a space voltage vector calculating and outputting unit. Through the method provided by the invention, the space voltage vector of controlling the motor in the next period can be acquired by utilizing the efficient value formula of each-phase electromotive force of a motor stator (UE is equal to 4.44kfNF), namely the ratio of the voltage vector amplitude to the phase gain is maintained as a constant when the motion track of a stator flux linkage vector is a flux linkage circle. In the invention, only the torque single proportional-integral (PI) regulating loop is required, thus the system structure is simplified, the dynamic property of the system is enhanced, and the high-performance control of the driving system of the three-phase induction motor is realized.

The invention provides a starting method of a 3-phase induction motor. Compared with a basic starting method, the starting method is advantaged in that the temperature increase amplitude of the 3-phase induction motor during the starting process of a decanter type centrifuge can be reduced. By means of the starting method of the 3-phase induction motor, a revolving drum of a decanter type centrifugal separator carrying out centrifugal separation on an object to be processed rotates faster from a stop state to a target speed. The starting method is characterized in that by employing a star connection mode, a power supply is electrically connected with the 3-phase induction motor, a thyristor is employed to shear waveform of voltage supplied from the power supply to the 3-phase induction motor while the 3-phase induction motor is started, furthermore, when the current effective value of the 3-phase induction motor is reduced in the starting process, a process for increasing the conduction angle of the thyristor is carried out.

The invention relates to a method for determining a threshold value of a multi-working-system three-phase induction motor protection system, belongs to the technical field of motor control, and solvesthe problem that an action value of an inherent protection control system of a motor does not allow the motor to operate in other load modes. The method comprises the following steps of calculating electromagnetic torque, and determining the overload capacity of the motor; establishing a dynamic mathematical model of the motor, and calculating the current of a winding; determining the loss in themotor; establishing a fluid-temperature temperature field three-dimensional coupling analysis model of the three-phase induction motor; driving the temperature rise values during different load operation according to the three-phase induction motor under the short-time working system, and determining the short-time working time limit when the motor drives the load to operate in an overload mode;and calculating the starting time and the running current during overload running of the motor, determining the threshold value of the protection action during short-time overload running of the motoraccording to the current value and the setting requirements of overload protection, over-current protection and short circuit protection of the motor, and determining the starting time value of the motor over-current protection required to be hidden. According to the method, the safety guarantee is provided for the operation of the motor in the multi-load mode.

The preferred embodiment the invention proposes pertains to a three-phase induction motor, and operates on the premises of having the extension cords on two ends of the motor embedded with several balancing eccentric washers and a balancing eccentric block added, of which the eccentric block contains a sleeve bearing, and one end of the eccentric block is fitted with a bolt, with the bolt head covered with rubber; o-ring is fitted between the balancing eccentric washer and balancing eccentric block, whereby using the invention's frequency changer for controlling an AC 3-phase induction motor serves to generate multiple frequencies for generating different amplitudes, which can be use to control the speed and load emitted between the eccentric block and balancing eccentric washer.

The invention discloses a three-phase induction motor fault analysis method based on a spiking neural membrane system. A forward fault prediction reasoning algorithm and a reverse tracing fault diagnosis reasoning algorithm are provided based on an improved fuzzy reasoning real number spiking neural membrane system. Before the three-phase induction motor breaks down, a motor is started, fault prediction is performed on the three-phase induction motor through a forward fault prediction reasoning algorithm, so that possible faults of the three-phase induction motor can be effectively predicted; and after the three-phase induction motor breaks down, fault diagnosis is conducted on the three-phase induction motor through a reverse cause tracing fault diagnosis reasoning algorithm, and the fault cause and the fault source causing the fault can be effectively determined. The three-phase induction motor fault analysis model based on the improved fuzzy reasoning real number spiking neural membrane system is established from the perspective of the whole machine, and the defect that accurate fault causes and fault sources are difficult to find after faults occur in an existing method is effectively overcome.

A method for operating an unbalanced load manager for a three-phase induction motor or heater, includes receiving, by a load manager, values representative of current flow sensed by current sensors and voltages sensed by voltage taps corresponding to phases of a three-phase power system providing power to the motor or heater. The method includes detecting, by the load manager, a transition from positive or negative to zero current, to measure a phase shift between line-to-line and current. The method further includes synchronizing, by the load manager, firing from line-to-line signal to line-to-neutral signal of phases of the three-phase power system, using the measured phase shift between line-to-line and current.

The invention provides a compact low-noise three-phase induction motor which comprises a motor base. A stator is sleeved in the motor base in a heating mode. Front and rear end covers are installed atthe two ends of the motor base respectively, and a rotating shaft is installed in the motor base and supported and fixed through front and rear bearings. A rotor and an inner fan are sleeved on therotating shaft, andan outer fan is arranged at the tail end of the rotating shaft. A fan cover is installed at the rear end of the motor base. The compact low-noise three-phase induction motor is characterized in that the motor base is provided with novel heat dissipation ribs; the front end cover is provided with a novel guide plate; and rotor short-circuit ring blades and the inner fan form a novel inner fan device. Heat dissipation ribs are arranged on the surface of the fan cover, and a special air guide cylinder is installed in the 2P motor. The motor is compact in structure, low in noise, attractive in appearance, small in vibration and low in cost.

The preferred embodiment the invention proposes pertains to a three-phase induction motor, and operates on the premises of having the extension cords on two ends of the motor embedded with several balancing eccentric washers and a balancing eccentric block added, of which the eccentric block contains a sleeve bearing, and one end of the eccentric block is fitted with a bolt, with the bolt head covered with rubber; o-ring is fitted between the balancing eccentric washer and balancing eccentric block, whereby using the invention's frequency changer for controlling an AC 3-phase induction motor serves to generate multiple frequencies for generating different amplitudes, which can be use to control the speed and load emitted between the eccentric block and balancing eccentric washer.

The invention provides a three-phase induction motor star-delta starting control method and device. The device comprises a current and voltage detection unit, a single-chip microcomputer control unit, a human-computer interaction unit, a delta connection switching device based on a solid-state relay and an AC contactor, a star connection switching device based on the solid-state relay, a main circuit AC contactor and a thermal relay device. The current and voltage detection unit is connected on a bus and used for detecting power current and power voltage signals in real time so as to act as the basis of trigger control of the single-chip microcomputer control unit. The single-chip microcomputer control unit is connected with the current and voltage detection unit. The human-computer interaction unit is connected with the single-chip microcomputer control unit. Starting current of the starting instant of star connection can be effectively suppressed so that the current impact of star-delta switching can be reduced, the electromagnetic interference caused by disconnection of a stator winding in the star-to-delta process can also be reduced and thus noise and vibration of starting of an asynchronous motor can be greatly reduced.

The invention discloses an instantaneous power detection and load identification based induction motor cooperative control system which realizes energy-saving control on a light-loaded or unloaded three-phase induction motor and mainly comprises an instantaneous power detection and load identification cooperative controller using a digital signal processor TMS320F28346 as a core, a three-phase bridge power amplifier, a three-phase bridge driving circuit, the three-phase induction motor, a three-phase diode rectifier bridge, an instantaneous power detection link, a current detection link, a coder rotating speed detection link, a load identification link, a +24V switch power source, a +15V switch power source, a + / -12V switch power source, a +5V power source and the like. An instantaneous power detection and load identification based induction motor cooperative control method is adopted to control stator exciting current of the light-loaded or unloaded three-phase induction motor, and power factors of the three-phase induction motor are adjusted by load rate obtained on the basis of load identification, so that operating efficiency of the three-phase induction motor is effectively improved, and good electricity-saving effect is achieved.

The present invention provides an electronic braking system for an irrigation machine. According to an exemplary preferred embodiment, the present invention includes a drive controller which includesa power supplying circuit which signals an ON condition when a motive power request is input into the drive controller and an OFF condition when motive power is not input into the system. According toa further preferred embodiment, the present invention further includes a 3-phase induction motor connected to apply torque to a drive shaft which is connected to a least one drive wheel. According toa further preferred embodiment, the power supplying circuit supplies 480V AC of motive power to the drive motor when the drive controller signals the ON condition and 10-80V DC of non-motive power toat least one phase of the motor when the drive controller signals the OFF condition. According to a further preferred embodiment, the application of the DC current is applied immediately after the motive power is removed from the drive motor and the application of non-motive power brakes and prevents the drive shaft from turning until the DC current is removed.

The invention discloses a vector observation method for estimating the rotor position and speed of an electric forklift motor, using a low-resolution motor rotor position sensor, such as a Hall element, a low-precision incremental photoelectric encoder of 80 or 100P / R, and constructing A vector observer realizes the indirect measurement of the rotor position angle and rotational speed of the phase induction motor; the present invention proposes an algorithm through harmonic decoupling, from the discrete rotational position vector H αβ The vector tracking observer, which extracts continuous rotor position information from the vector tracking observer, realizes the accurate estimation of the rotor position angle and the accurate measurement of the rotational speed of the three-phase induction motor using the low-resolution rotor position sensor.