154 results about "Phase inductance" patented technology

The invention discloses a four-phase and double-salient brushless direct current motor with symmetrical phase inductances. According to the four-phase and double-salient brushless direct current motor, a unit motor is of a novel 12 / 9 salient structure or a novel 12 / 15 salient structure, each excitation element is wound after spanning three stator poles, each stator coil of each phase stator winding is distributed at different positions, and the symmetry of the phase inductances is achieved by a mode of symmetrically distributing the four phase stator windings; the pole-arc coefficient matching size of motor stators and rotors is determined by theoretical analysis and emulation verification methods, so that the phase inductances of the motor are hoisted and decreased by an electrical angle of 180 degrees, the total permeance of exciting windings remain basically unchanged, the positioning torque of the motor is small, and the four phases are electrified at the same time to operate. In addition, the four phase stator windings are independent in pairs, so that the motor can operate by only using the two phases after one phase is in fault, and the fault tolerance performance is favorable. Moreover, the total permeance of the exciting windings is unchangeable, so that the four-phase and double-salient brushless direct current motor has the advantages of small positioning torque and the like.

The invention discloses a method for initially positioning and starting a switched reluctance motor without a position sensor, and belongs to the technical field of control of the switched reluctance motor. The method comprises the following steps of: setting an inductance bottom threshold value LLow and an inductance top threshold value LHigh based on the basic characteristic that the inductance of the switched reluctance motor periodically changes with the position of a rotor; injecting short pulses into each phase winding and calculating inductance values according to a phase voltage equation; judging phases which can be currently switched on according to the relation among each phase inductance calculated value and LLow and LHigh and selecting estimated phases of an initial position angle at the same time; and establishing a phase inductance mathematical model to obtain angle information in the selected phases by using the relation between the inductance mathematical model and the inductance calculated values. Though the method, an initial switch-on phase selection signal can be accurately acquired and the initial position angle of the rotor can be calculated at the same time, so the switched reluctance motor can be started and initially positioned without the position sensor, an algorithm is simple and generality is high.

The invention discloses a method for estimating the rotor position of a switched reluctance motor without a position sensor, and belongs to the technical field of the control of the switched reluctance motors. In the method, based on the fundamental feature that an inductor of the switched reluctance motor is changed periodically with the rotor position, phase inductance reaches maximum at a position where a stator is aligned with a rotor, so the slope of the phase inductance is changed into negative from positive at the maximum position of the inductance, and slope zero-crossing points exist. In the method, by sampling each phase current and phase voltage in real time, each phase inductance value can be detected in real time, and simultaneously, the inductance slope can be calculated; the calculated inductance slope is subjected to zero balancing to obtain pulse signals of the slope zero-crossing points, so that a zero-crossing position, namely the position where a stator tooth pole is aligned with a rotor tooth pole can be detected; and the phase difference of the two adjacent maximum inductance positions is 45 degrees, so the difference of positions of the two slope zero-crossing points is 1 / 8 cycle, and the real-time rotate speed and rotor position information of the motor can be calculated according to the zero-crossing pulse signals. The method has the advantages of independent of parameters of a motor body, no need of measurement of motor characteristics such as static flux linkage and the like, simple algorithm and easy realization, so the method has strong generality compared with a non-position strategy.

The invention discloses a position-sensor-free control method suitable for four-quadrant operation of a switch reluctance motor, and belongs to a switch reluctance motor control method. The position-sensor-free control method comprises the following steps of constructing a simplified inductance model according to a fourier series expression of inductance of the switch reluctance motor; fitting a function relation in which an inductance model parameter is changed along with phase current by measuring inductances at three special positions of the switch reluctance motor at different phase currents on line, and constructing a non-linear inductance model of the switch reluctance motor; deriving an analysis formula for estimating a position of a rotor of the switch reluctance motor through phase inductance according to the non-linear inductance model; and when the motor runs, detecting the phase current and phase voltage in real time, estimating an excitation phase magnetic chain according to a voltage equation to obtain excitation phase inductance, calculating the current position of the rotor according to the estimation analysis formula by using the derived position of the rotor, and realizing sensor-free running control over the switch reluctance motor according to the estimated position of the rotor. The algorithm is simple, small in calculated amount, favorable for real-time implementation of a micro controller and higher in position estimation precision.

The invention discloses a built-in permanent magnet synchronous motor sensor-less control method. According to the control method, a rotary high-frequency injection method is adopted, so that phase inductances are calculated; through the symmetry and the alternating characteristic of the phase inductances, the difference of every two phase inductances is obtained, so that the differences of the phase inductances are obtained to eliminate a direct current component among the phase inductances; iterative summation calculation is carried out on the differences of the phase inductances, theoretically, a series of infinitely fractionized inductances can be obtained; simple comparison calculation is carried out on the fractionized inductances, so that the current position of a rotor is determined and obtained according to the inductance with the maximum amplitude; according to the position of the rotor, the estimated speed and a three-phase low-frequency current, a motor is driven to operate through a vector control method. Conversion of coordinates and a salient pole tracking algorithm are not needed in the estimation process of the position of the rotor, the control structure is simple and reliable, and engineering realization is easy.

The methods and devices provided herein include methods and devices for controlling a permanent magnet motor. In one implementation, a method is provided that allows for the determination of the values of the phase back EMF voltage and of the phase inductances while the phases are powered with a PWM (Pulse Width Modulation) controlled current and / or voltage.

The invention discloses a method for controlling a position-less sensor of a switched reluctance motor, and belongs to the technical field of switched reluctance motor control. The method comprises the following steps of: based on the basic characteristic that the inductance of the switched reluctance motor is periodically changed along with a rotor position, establishing a precise inductance mathematical model according to an inductance characteristic curve, and setting an inductance threshold value of a turn-on / turn-off angular position by using the mathematical model; sampling current and end voltage of each phase, and calculating real-time inductance; and comparing the phase inductance calculation value of the current estimation phase with the inductance threshold value of the turn-off angular position of the phase and the inductance threshold value of the turn-on angular position of the next turn-on phase respectively to obtain a turn-off signal of the current estimation phase and a turn-on signal of the next turn-on phase so as to directly acquire a driving signal of each phase and realize the operation of the position-less sensor. The algorithm can realize turn-on / turn-off angle control by adopting a method for directly estimating the driving signal, meets the requirement of motor optimization control, and is simple and convenient to implement.

A multi-phase switching voltage regulator having asymmetric phase inductance includes a controller and a plurality of power stages each configured to deliver output current to a load through an inductor. At least one of the inductors has a higher open circuit inductance than the other inductors so that at least one of the power stages has a different output inductance compared to the other power stages. The controller is configured to control switching of the power stages so as to regulate an output voltage of the multi-phase switching voltage regulator, including allowing all of the power stages to provide current to the load through the respective inductors during a full power event at the load and preventing all of the power stages except for the at least one power stage having the higher open circuit inductance from providing current to the load during a low power event at the load.

The invention discloses a vacuum cleaner, a control method, device and system for a brushless DC motor, wherein the method comprises the following steps: offline obtaining a temperature-phase resistance meter and a temperature-phase inductance meter of the motor; in a low-speed operation phase of the motor, during the high-level time of each PWM control cycle, obtaining a conducting phase positive-side voltage, a conducting phase negative-side voltage, a non-conducting phase opposite potential voltage, a bus current instantaneous value and the current winding temperature, and obtaining phase current corresponding to any two moments; obtaining the phase current change rate of the motor according to any two moments and the corresponding phase current, and obtaining the phase resistance and phase inductance of the motor according to the current winding temperature, the temperature-phase resistance meter, and the temperature-phase inductance meter; obtaining a flux linkage value of the motor according to the aforementioned parameters, and judging whether the flux linkage value is greater than a commutation threshold; if yes, performing commutation. Thereby, the accurate commutation ofthe motor can be realized in the low speed operation phase of the motor, the motor can be prevented from being out of step, and the reliability is high.

A system (100) has a motor controller (102), an actuation circuit (104, 106, RSNS), and a sensorless, brushless DC motor (108). 2N voltage pulses are generated for 2N pairs of phases of motor (108). A current is sensed for each of the 2N pairs of phases, to determine a phase inductance from the sensed current for each of the 2N pairs of phases. The determined phase inductances are compared to a look-up table to determine the initial position of motor (109).

An embodiment of the invention discloses a high-voltage direct-current circuit harmonic impedance analysis equivalent model and a high-voltage direct-current circuit harmonic impedance frequency analysis method, aiming to solve the problems that a harmonic current path in a typical converter model is limited between a converter transformer and a valve bridge, stray capacitance to ground of converter transformer sleeves is ignored, and a large difference exists between a design result and an actual measurement result of the model based on a direct-current-side harmonic current theory. The high-voltage direct-current circuit harmonic impedance analysis equivalent model comprises a current converter adopting a three-pulse converter model, and the three-pulse converter model comprises a leakage current path and a converter bridge. The high-voltage direct-current circuit harmonic impedance analysis equivalent model is more accurate by taking the nature that harmonic waves are reflected by 3n times under the effect of commutation induction of the leakage current path and the converter bridge into consideration; the influences of an alternating-current system and an alternating-current filter on high-voltage direct-current circuit resonance characteristics are taken into account, so that an analysis process of the high-voltage direct-current circuit resonance characteristics is more accurate and rigorous, and results are more reliable.

The invention relates to a linear modeling method of a switch reluctance motor memristor. A linear phase inductance characteristic element of a switch reluctance motor is established by adopting an in-phase operational amplifier circuit and an anti-phase operational amplifier circuit; the angular velocity of the switch reluctance motor is integrated by a proportional circuit and an integral circuit to obtain a rotor position angle of the switch reluctance motor memristor to be used as the input of the linear phase inductance characteristic element of the switch reluctance motor; the phase inductance of the switch reluctance motor is obtained in accordance to the output of the established linear phase inductance characteristic element of the switch reluctance motor; a current reversal circuit is connected between the input end of a multiplier and the output end of the multiplier; the output end of the linear phase inductance characteristic element of the switch reluctance motor is connected to the other input end of the multiplier; the input voltage is accessed into the input end of the multiplier; and a relation exists between the output current and the input voltage as well as between the output current and the phase inductance value. According to the linear modeling method disclosed by the invention, the resistance value of the memristor changes along with change of the rotor position. The linear modeling method lays a foundation on establishment of a complete switch reluctance motor circuit and is beneficial to real-time control.

The present invention provides an improved model and methodology for simulating motor performance which allow increased control accuracy at the higher currents, higher speeds, and / or higher current change rates required in modem mass storage devices. In addition, the invention provides methods for simulating motor performance, and for testing a motor commutation scheme. The model includes a plurality of phases extending between first ends joined at a center tap and second ends extending outward from the center tap to a corresponding plurality of phase taps, and a mutual inductance component disposed between two of the phases, wherein the mutual inductance and / or the phase inductance components may be a function of rotor position and / or current.

In an embodiment, a power-supply controller includes switching circuitry and an adjuster circuit. The switching circuitry is configured to cause a charging current to flow until the charging current has a predetermined relationship to a threshold, and to cause a discharging current to flow to an output node that carries an output voltage after the charging current. And the adjuster circuit is configured to adjust the threshold such that a ripple voltage superimposed on the output voltage has an approximately constant magnitude. For example, a power supply may include such a power-supply controller to maintain the magnitude of the output ripple voltage within a particular range during a pulse-frequency-modulation (PFM) mode despite variations in one or more parameters such as input voltage, output voltage, filter capacitance, phase inductance, and charging-current-sense impedance, from their respective nominal values.

A controller (72) for a switched reluctance machine (20) implements a model of at least one active phase representing dynamic magnetic machine characteristics. The controller (72) determines machine control signals based on rotational position obtained by numerically solving the model with measured machine operating parameters. The model may be implemented as the sum of orthogonal functions relating active phase voltage and current with constants derived from phase inductance to obtain the rotor angle.

The invention discloses a rotor rotating speed / position detecting method of an aero-switch reluctance starting / power generator. Through coaxially mounting a switched reluctance motor of which the number of teeth is same with that of one selected from a stator and a rotor on the aero-switch reluctance starting / power generator as a position detector, namely a switched reluctance type position detector is coaxially mounted. The position detector realizes estimation for per-unit value of each phase of inductance, thereby acquiring a rotor position signal by means of a correspondence between a phase inductance and a rotor position angle, and supplying accurate and reliable position and rotating speed information for the aero-switch reluctance starting / power generator. The rotor rotating speed / position detecting method of the aero-switch reluctance starting / power generator is suitable for adverse operation environments of high-temperature operation environment, high-speed operation environment, smeary environment, etc. Furthermore the rotor rotating speed / position detecting method of the aero-switch reluctance starting / power generator has advantages of high detecting precision, high reliability, simple structure, high firmness, high stability and relatively low cost of a detecting system, high sensitivity and high efficiency in detecting an output response, and high suitability for position detection in high-temperature and high-speed operation of the aero-switch reluctance starting / power generator.

A staggered parallel-connection direct-current voltage reduction converter with a phase-by-phase coupled inductor of the invention comprises power switch tubes, a filtering capacitor and a coupled inductor possessing n windings. In the coupled inductance windings, a first phase inductance winding is coupled with a second phase inductance winding; the second phase inductance winding is coupled with a third phase inductance winding; an n-1th phase inductance winding is coupled with an nth phase inductance winding; the nth phase inductance winding is coupled with the first phase inductance winding; except the first phase inductance winding and the nth phase inductance winding, a mth phase inductance winding is only coupled with a m-1th phase inductance winding and a m+1th phase inductance winding and is not coupled with other windings; the first phase winding is only coupled with the second phase winding and the nth phase winding, and the nth phase winding is only coupled with the first phase winding and the n-1th phase winding. An array-type magnetic core is used to realize phase-by-phase coupling of n phase coupled inductance windings. Through designing an inductive coupling coefficient and controlling conduction time of a main switch tube, an output current ripple of the converter is reduced and dynamic response is increased.

The invention discloses a fault detection method and apparatus of a brushless direct current motor. The fault detection method includes the following steps of controlling the upper bridge arm switch of any one phase of the three-phase stator winding to be on and controlling an inverter to drive the lower bridge arm switches of the other two phases of the three-phase stator winding to on when the fault testing instruction is received; acquiring the bus voltage value of the brushless direct current motor and the steady-state current value of any one of the other two phases of the three-phase stator winding; calculating the phase resistance of the three-phase stator winding of the brushless direct current motor according to the bus voltage value and the steady-state current value; acquiring the phase inductance according to the phase resistance and steady-state current drop time; and determining the stator of the brushless direct current motor to be not matched and outputting the corresponding alarm signals when the phase resistance and the phase inductance of the three-phase stator winding. The fault that the stator winding of the brushless direct current motor does not match with the brushless direct current motor can be detected during the general assembly test.

The methods and devices provided herein include methods and devices for controlling a permanent magnet motor. In one implementation, a method is provided that allows for the determination of the values of the phase back EMF voltage and of the phase inductances while the phases are powered with a PWM (Pulse Width Modulation) controlled current and / or voltage.

In an embodiment, a power-supply controller includes switching circuitry and an adjuster circuit. The switching circuitry is configured to cause a charging current to flow until the charging current has a predetermined relationship to a threshold, and to cause a discharging current to flow to an output node that carries an output voltage after the charging current. And the adjuster circuit is configured to adjust the threshold such that a ripple voltage superimposed on the output voltage has an approximately constant magnitude. For example, a power supply may include such a power-supply controller to maintain the magnitude of the output ripple voltage within a particular range during a pulse-frequency-modulation (PFM) mode despite variations in one or more parameters such as input voltage, output voltage, filter capacitance, phase inductance, and charging-current-sense impedance, from their respective nominal values.

The utility model discloses a switch reluctance motor rotor-less position sensor control method. According to the method, one main switch in a power converter is opened, a phase winding of the switch reluctance motor is excited by positive voltage, a current of the phase winding increases firstly till the current of the phase winding reaches to a peak value, then the current of the phase winding decreases to a valley value position, the current of the phase winding continuously increases again, the valley value position of the current of the phase winding is a largest-phase-inductance initial end rotor position, the largest-phase-inductance initial end rotor position is acquired and is directly taken as a switch-off position of the main switch of the switch reluctance motor power converter, and the main switch of the power converter is switched off. The method does not need to have a rotor position sensor and does not need to store motor linkage data, and the method further has advantages of strong timeliness, dynamic response performance, good stability and relatively strong practicality and versatility.

The invention relates to the technical field of power electronics, and provides a three-phase inductor and a power module. The current flowing through each inductor comprises a power frequency currentcomponent and a high frequency current component. The three-phase inductor comprises a magnetic core and a winding, the magnetic core comprises a first cover plate, a second cover plate and a magnetic column unit, the first cover plate and the second cover plate are oppositely arranged, and the magnetic column unit is clamped between the first cover plate and the second cover plate; the first winding is wound on the first magnetic column and the second magnetic column of the first magnetic column unit, and a first current flowing through the first winding surrounds the first magnetic column and the second magnetic column in opposite directions; the second winding is wound on the first magnetic column and the second magnetic column of the second magnetic column unit, and a second current flowing through the second winding surrounds the first magnetic column and the second magnetic column in opposite directions; and the third winding is wound on the first magnetic column and the secondmagnetic column of the third magnetic column unit, and a third current flowing through the third winding surrounds the first magnetic column and the second magnetic column in opposite directions.

The invention provides a method, a device and equipment for controlling energy storage converter off-grid output voltage, and a medium. The control method comprises the following steps: acquiring an output voltage reference value, a three-phase output voltage, a three-phase inductive current and a three-phase capacitive current of an energy storage converter; performing proportional integral control on the voltage loop of the energy storage converter according to the output voltage reference value and the three-phase output voltage to obtain an inner loop current given value; performing proportional resonance control on the current loop of the energy storage converter according to the inner loop current given value, the three-phase inductive current and the three-phase capacitive current to obtain an off-grid voltage control signal; and controlling the off-grid voltage output of the energy storage converter according to the off-grid voltage control signal. According to the invention, the tracking capability of the inductive current can be accelerated, the influence of sudden change of the load current on the output voltage is solved, and the output voltage of the energy storage converter is kept stable during off-grid work, so that the stability of the load power supply voltage is improved.

The invention discloses a 12 / 6-pole hybrid rotor structure magnetic suspension switched reluctance generator and a control method thereof. A stator of the generator has 12 tooth poles, each stator tooth pole is wound by a winding, a rotor is formed by axial superposition of 6 tooth poles and a disc and has no windings. The pole width of salient poles of the generator stator is the same as that of salient poles of the rotor. The structure enables inductance of each phase to have a 1 / 2 cycle to be located in a flat area of the bottom, 1 / 4 to be located in a rising area, and 1 / 4 to be located in a falling area. In power generation operation, only three phases in a mechanical structure which form 120 degrees with one another and whose inductance is located in the flat area and the rising area are conducted, each phase independently controls generation of suspension force and provides excitation for a power generation stage, and the rest three phases located in the inductance falling area generates electricity with follow current. The novel generator integrates a radial magnetic bearing and a switched reluctance motor, rotor pole braking torque is large, generated output is large, influence of suspension phase current on power generation phase current is small, and the radial load capacity is high.

A multiphase magnetic integration coupling inductor comprises a U-type iron core, a T-type iron core and coils; the magnetic pillars of the T-type iron core are positioned between magnetic pillars of the U-type iron core; an air gap group is formed between the magnetic yoke of the T-type iron core and each magnetic pillar of the U-type iron core; another air gap group is formed between the magnetic yoke of the U-type iron core and each magnetic pillar of the T-type iron core; each magnetic pillar of the U-type iron core are winded by the coil. The advantages are that the multiphase magnetic integration coupling inductor is applied to coupling integration of each phase inductor in an interleaving switch power supply, thus improving symmetry level of each phase inductance parameters, simplifying iron core coupling structure, reducing coil length, saving copper material, reducing coil copper loss, reducing power supply output current and voltage ripples, reducing power supply output filter capacitance, and improving power supply efficiency and dynamic response speed .

The invention relates to a brushless direct current motor rotor position detection method based on single-phase inductance detection. The brushless direct current motor rotor position detection methodincludes the following steps that a detection vector with the time duration being delta T1 is applied to a motor stator winding, the detection phase current is sampled at the beginning and end of vector application correspondingly, and the current change rate is obtained through subtraction of two values; a driving vector with the time duration being delta T2 is applied to the motor stator winding to drive a motor to run; induction energy is released slowly and the motor driving current is maintained by applying a circulation follow current vector in the remaining time of the control period;the variation trend of frac{d}{d<t>} is judged; and the execution steps are repeated continuously after a motor rotor passes through a switching point, and the motor rotor is switched to the next section after waiting for a delay at an electrical angle of 30 degrees.

The invention discloses an intelligent detection apparatus for alternating-current filter inductance of an inverter. The intelligent detection apparatus comprises an A-phase inductance voltage detection unit, a B-phase inductance voltage detection unit, a C-phase inductance voltage detection unit, an A-phase inductance current detection unit, a B-phase inductance current detection unit, a C-phase inductance current detection unit, a sampling circuit, a controller, a display device, and a single-stage / dual-stage inverter topological unit. The sampling circuit consists of a first-stage difference proportional circuit, a second-stage voltage conditioning circuit, a third-stage emitter follower circuit, a fourth-stage filter circuit, and a fifth-stage amplitude limiting circuit. According to the invention, a method for inductance fault detection based on devices carried by an inverter is provided. No detection instrument and manpower cost are increased; the intelligent effect of the inverter fault detection is realized; the installation and maintenance staff can carry out operation conveniently; and reliability and stability of the inverter system are improved.

The invention provides a novel sensorless initial positioning method of a switched reluctance motor, and belongs to the field of switched reluctance motors. The method comprises the following steps: predicting a feedback current peak value at an intersection point position of two phase inductors through a threshold value automatic identification strategy, and obtaining current threshold values at two special positions according to the height linearization of the inductance of a rotor inductance rising area of the switched reluctance motor; and carrying out the sector judgment and high-precision initial position estimation by comparing the magnitude relationship between a feedback current peak value detected by pulse injection and a corrected current threshold value. According to the method provided by the invention, the initial conduction phase can be accurately controlled, and non-reverse-rotation starting of the motor can be realized; according to the method, the current threshold value is obtained through an automatic measurement program, a large amount of time consumed by manual measurement is avoided, the threshold value is subjected to voltage correction, the influence of voltage fluctuation is effectively overcome, the turn-on angle and the turn-off angle of the turn-on phase during low-speed operation are adjustable, single-beat and double-beat operation can be achieved, and the operation state of the motor is optimized.

A multi-phase transformer provided by the invention comprises a shell and an inductance transformation unit, the inductance transformation unit comprises a magnet assembly, a primary coil, a secondarycoil and an inductance coil; at least three placing spaces are formed in the shell, a blocking wall of the shell is blocked between two adjacent placing spaces, and an inductance transformation unitis arranged in each placing space; a first coil placement position and a second coil placement position are formed in the magnet assembly, the inductance coil is arranged in the first coil placement position, the primary coil and the secondary coil are arranged in the second coil placement position, and the inductance coil is connected with the primary coil in series. The shielding effect among the multi-phase inductance transformation units is ensured by the independent placement space; the primary coil and the secondary coil are concentrically arranged to reduce the volume of the magnet assembly, thereby reducing the volume of the multi-phase transformer; one-time resin encapsulation can be carried out in the shell, the heat dissipation performance of the product is guaranteed, the production efficiency is improved, only one-time positioning installation is needed when the multi-phase transformer is installed on a circuit, the installation difficulty is reduced, and the efficiency isimproved.