CN115549531A - Rotor information estimation method based on back electromotive force observation under dq axis - Google Patents
Rotor information estimation method based on back electromotive force observation under dq axis Download PDFInfo
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- H—ELECTRICITY
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- H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
- H02P6/00—Arrangements for controlling synchronous motors or other dynamo-electric motors using electronic commutation dependent on the rotor position; Electronic commutators therefor
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- H02P2203/00—Indexing scheme relating to controlling arrangements characterised by the means for detecting the position of the rotor
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Abstract
The invention discloses a rotor information estimation method based on dq-axis counter electromotive force observation, and belongs to the technical field of power generation, power transformation or power distribution. The proposed algorithm for observing the back electromotive force under the dq axis does not involve any differential operation, is not sensitive to high-frequency noise, and does not need any filter. And meanwhile, three back electromotive force data processing methods are provided and combined with a phase-locked loop to estimate rotor information, wherein the simplest method only needs to calculate the back electromotive force on the d axis, and the performance requirement on a processor is greatly reduced. The rotor information estimation and estimation method is used for the position-free control, can effectively reduce the operation complexity of a position-free control system, and has good dynamic performance and steady-state precision. In addition, the rotor information estimation method is combined with a parallel type rotating speed current regulator for use, so that the position-free control system can quickly compensate the torque in a low-speed domain, the rotating speed is quickly stabilized under load disturbance, and the low-speed load carrying capacity and the rotating speed characteristic of the position-free control system are effectively improved.
Description
Technical Field
The invention relates to a back electromotive force observation method of a three-phase Permanent Magnet Synchronous Motor (PMSM) in a Synchronous rotating coordinate system (d-q coordinate system), and calculates the position and the rotating speed of a rotor through a phase-locked loop technology.
Background
The Field-oriented control (FOC) has become one of the standard technologies in the Field of variable frequency speed control, however, the FOC is very dependent on the rotor position information, and although the above problems can be solved by using a mechanical position sensor, the mechanical position sensor also faces several outstanding problems, namely difficult installation and easy damage. Therefore, the development of the position-free control technology is very important for expanding the application range of the three-phase electric drive system. Currently, the position-free control technology has been successfully applied in the field of household appliances, and the application occasions are characterized in that the motor has higher running rotating speed and low requirements on dynamic performance. Besides the field of household appliances, the position-free control technology has urgent application requirements in the fields of ship electric propulsion, wind power generation, starting/power generation of aircraft engines and the like. However, given the poor dynamic performance of current position control-less systems, this technique faces significant challenges in the above-mentioned situations.
According to the rotating speed operating range, the position-free control technology can be divided into medium-high speed domain position-free control and low-speed domain position-free control. Generally, the medium-high speed region corresponds to 1/4 to 2 times of the rated rotation speed, and the low speed region can be represented by an electrical frequency within several hertz. The method is suitable for a plurality of position-free control methods in medium and high speed areas, wherein a position-free control algorithm based on a motor model occupies a dominant position, and the position-free control method can be divided into an anti-electromotive observation method and a flux linkage observation method according to different observation targets. Usually, the back electromotive force observation is performed under a two-phase static coordinate system (α - β coordinate system), because the α - β coordinate system motor model does not contain rotor position information, the back electromotive force observation algorithm can achieve decoupling from the rotor position, however, since the back electromotive force observation method uses rotation speed information to assist the back electromotive force observation, the rotor position decoupling relationship is not complete. Therefore, a flux linkage observer free of rotor position and rotation speed information is proposed in the paper "surface-mounted permanent magnet synchronous motor position-less sensor control technology based on a nonlinear observer", by honor Ji, li, but the flux linkage observer is relatively complex in structure, and the flux linkage observation precision is reduced due to the existence of integral errors. Therefore, back emf observation remains a technique that is currently widely used. According to whether the observer is closed-loop or not, the inverse electromotive force observation algorithm can be divided into an open-loop observation algorithm and a closed-loop observation algorithm, the traditional open-loop inverse electromotive force observation algorithm has differential operation and differential noise, and the use of a filter limits the dynamic performance of the system without position control. The prerequisite condition of the closed-loop observation algorithm is that the estimated rotating speed is stable, and the observation back electromotive force also contains strong high-frequency noise due to the use of a large-gain control link, and a filter cannot be exempted. Aiming at the defects of a closed-loop observation algorithm, an extended back electromotive force observation method of a three-phase permanent magnet synchronous motor provides a filter-free alpha-beta coordinate system open-loop back electromotive force observation algorithm, and a sine and cosine function required by vector transformation is calculated by combining a complex coefficient filter and a normalization algorithm, but the structure is still complex.
The invention further simplifies the current back electromotive force observation algorithm, aims to improve the steady-state and dynamic performances of the system without the position control system, enables the system to be close to the performances of the system with the position control system, and meets the urgent requirements of middle and low-end industrial scenes on the technology without the position control.
Disclosure of Invention
The invention aims to provide a rotor information estimation method based on back electromotive force observation under dq axis aiming at the defects of the control technology without a position sensor, which can realize closed-loop tracking of the rotor position only by utilizing the back electromotive force information on d axis and matching with a phase-locked loop technology under the conditions of small rotating speed variation range and low control precision requirement, realize the invention aim of accurately estimating the rotor information by smaller calculated amount and solve the technical problem that the real-time estimation of the rotor information is influenced by large calculated amount of a back electromotive force observation algorithm under the existing static coordinate system.
The invention adopts the following technical scheme for realizing the aim of the invention:
neglecting the nonlinear characteristic of a stator core, and adopting a three-phase balanced sine wave power supply mode, the invention provides a back electromotive force real-time calculation algorithm under a synchronous rotation coordinate system for a surface-mounted motor, which can be specifically expressed as follows:
in the formula (1), the reaction mixture is,
and
respectively estimating the expanded back electromotive forces on the d axis and the q axis of the synchronous rotating coordinate system of the motor; u. of d And u q The voltage of the input end of the motor on the d axis and the q axis respectively; i all right angle d And i q The currents of the motor stator windings on the d axis and the q axis are respectively; r is s For the stator winding resistance of an electric machine
To estimate the rotational speed; l is a radical of an alcohol d And L q Stator inductances on d-axis and q-axis of the synchronous rotation coordinate system are respectively.
The expression of the real extended back electromotive force in the two-phase stationary coordinate system is as follows:
suppose that
For an estimated rotor position angle, θ is the true rotor position angle when
When the temperature of the water is higher than the set temperature,
so that only need to
And performing related data processing as the input of a phase-locked loop, and locking the phase-locked loop close to 0 through the closed-loop feedback of a PI regulator so as to realize the tracking of the rotor position.
Further, the above-mentioned pair
The following three methods can be specifically classified into the following methods:
first pair
The method for processing the related data comprises the following steps: is directly to
As an input to the phase locked loop. On the premise that the PI parameter of the phase-locked loop is proper, the dynamic performance and the steady-state performance of the phase-locked loop can change in the process that a position-control-free system changes the speed, and the dynamic response and the steady-state performance are poor at low speed and good; the dynamic response is fast at high speed, and the steady-state performance is poor. For systems with low control performance requirements and systems with poor controller computing capability, such as some fixed-point control chips and M0 series chips of ARM kernels, the method has the advantage of simple operation.
The second pair
The method for processing the related data comprises the following steps: will be provided with
As an input to the phase locked loop. Under the premise that the PI parameter of the phase-locked loop is proper, the method is
When the phase-locked loop is converged to 0, the dynamic performance and the steady-state performance of the phase-locked loop are not obviously different along with the change of the rotating speed. Compared with the method 1, the method has slightly increased calculation amount, but the control performance effect is improvedAs for chips with main frequency of about 100MHz, the method does not occupy too much computing resources.
Third pair
The method for processing the related data comprises the following steps: will be provided with
As an input to the phase locked loop. On the premise that the PI parameter of the phase-locked loop is proper, the dynamic performance and the steady-state performance of the phase-locked loop tend to be consistent in the full-speed domain range of the position-free control system, and the method is the method which works most stably. However, the method relates to evolution operation, and can be generally used for chips of more than M4 series of ARM inner cores, the dominant frequency of the chips of the series is more than 150MHz, and the method is suitable for controllers with strong calculation power.
The back electromotive force real-time calculation algorithm under the synchronous rotating coordinate system is combined with a phase-locked loop technology to realize the non-position control of the high dynamic performance of the PMSM, but a parallel type rotating speed current regulator is required to be utilized to improve the load carrying capacity and the rotating speed stability under the low speed. The specific description is as follows:
with i d Control policy of =0 is an example (but not limited to i) d =0 control), estimated rotational speed of the output of the phase-locked loop
With reference speed omega ref Differencing and serving as input to the speed regulator, the output of the speed regulator no longer being i q Is fed into the current loop, but directly at a reference voltage u q1 The three-phase driving signal is generated through coordinate transformation and comparison and a driving circuit, so that the traditional rotating speed current double closed loop is changed into rotating speed single loop control. The estimation angle without position control in the low rotating speed state is often more easily interfered by the outside world to cause larger estimation error, and the double closed loop system is slower in compensation of the moment, so that the rotating speed of the motor is seriously dropped and even stops rotating when sudden heavy load is caused. And the rotation speed single-loop control is adopted, so that when the position estimation error is not too large, i is quickly increased q The torque is compensated, so that the fluctuation of the rotating speed of the motor is small when the load is suddenly added or suddenly unloaded, and the stability of the position-free control system at low rotating speed is further improved.
The single rotation speed loop can realize quick compensation of the motor torque, but may cause the current i q The invention is improved on the basis of single-ring control of the rotating speed and can be described as follows:
sampling current i q To rated current i qmax Taking the difference as the input of the current loop, outputting the reference voltage u after passing through the current regulator q2 . U to the output of the speed loop q1 And u of current loop output q2 For comparison, take u q ＝{u q1 ,u q2 } min And serves as a reference voltage for the motor. When the motor is loaded suddenly and the load is within the motor bearing range, the current loop outputs u q2 The amplitude limiting is saturated, and the rotating speed ring quickly compensates the motor torque; when the load is higher than the motor bearing range, i is carried out q Greater than rated current i qmax Current loop output u q2 Desaturation, speed loop output u q1 The amplitude limiting is saturated, the rotating speed of the motor is reduced, and the current ring clamps the output current of the motor to be close to the rated current, so that the overcurrent of the motor is avoided. Since only one of the tacho loop and the current loop is in an active state, the control is also a single loop in nature, and the method is referred to as a parallel type tacho current regulator.
By adopting the technical scheme, the invention has the following advantages:
(1) The invention combines a back electromotive force real-time calculation algorithm under a synchronous rotating coordinate system with a phase-locked loop technology to realize the estimation of the position/rotating speed of the rotor, avoids the influence of a current differential term on a signal-to-noise ratio in the traditional extended back electromotive force observation algorithm, also avoids the distortion of the differential term easily caused when the load fluctuates, does not need any iterative operation, can reduce the use of a filter, and ensures that the steady state performance and the dynamic performance of a position-free control system are improved.
(2) Compared with a counter electromotive force algorithm combined orthogonal phase-locked loop technology under a static coordinate system, the rotor information estimation method provided by the invention has smaller calculation amount, 3 counter electromotive force combined phase-locked loop technologies are provided by the invention, and the most suitable counter electromotive force calibration method can be selected according to the calculation performance of the controller and the performance requirement of the control system.
(3) The rotor information estimation method provided by the invention is combined with the traditional double closed-loop regulator to realize the position-free control of the three-phase permanent magnet synchronous motor, and can also utilize the parallel type rotating speed current regulator to replace the traditional double closed-loop PI speed regulation system, the control structure is simple, the realization of a software algorithm is simple and easy, the torque can be quickly regulated through the rotating speed single closed loop to ensure the stability of the rotating speed, the defect of overlarge current during the rotating speed single closed-loop control can be avoided, the load carrying capacity and the rotating speed stability of the PMSM position-free control system are obviously improved, and particularly the problems of soft rotating speed characteristic and poor robustness of the position-free control technology in a low-speed domain can be improved in a low-speed operation stage.
(4) The counter electromotive force observation algorithm provided by the invention is obtained by simplifying a built-in three-phase permanent magnet synchronous motor model, and the algorithm is also suitable for a surface-mounted three-phase permanent magnet synchronous motor with a simpler model.
Drawings
Fig. 1 is a system block diagram of a three-phase PMSM position-control-free system according to the present invention.
Fig. 2 is a schematic diagram of a back electromotive force observation method based on a rotating coordinate system according to the present invention.
Fig. 3 is a first scheme for speed/position estimation of the back emf information by the phase locked loop.
Fig. 4 is a second scheme for speed/position estimation of the phase locked loop with respect to back emf information.
Fig. 5 is a third scheme for speed/position estimation of the phase locked loop with respect to back emf information.
FIG. 6 is a waveform of an experiment in which the motor was raised from 0 to 100rpm using the method of the present invention.
FIG. 7 is a graph of experimental waveforms for a motor raised from 100rpm to 200rpm using the method of the present invention.
Fig. 8 is a waveform of an experiment in which a motor is accelerated and decelerated at a full speed region using the method of the present invention.
Fig. 9 is an experimental waveform diagram of a load disturbance at low speed of a motor using a conventional double closed loop and the proposed back emf method.
Fig. 10 is an experimental waveform diagram of a motor employing the proposed parallel type tacho current regulator and the proposed back emf method for load disturbance at low speed.
Detailed Description
In order to make the implementation and technical advantages of the present invention more comprehensible, embodiments of the present invention are described in detail below with reference to the accompanying drawings.
The system block diagram of the three-phase PMSM without position control mentioned in the invention is shown in figure 1. The control system mainly comprises a parallel rotating speed current regulator, a coordinate transformation module, a comparison and drive circuit, a counter electromotive force real-time estimation module based on a rotating coordinate system and a phase-locked loop. When the motor load is not excessive, the reference rotation speed omega is given ref Sending into parallel type rotation speed current regulator, wherein the rotation speed regulator (ASR) is in effective state, the current regulator (ACR) is in saturated state, the output results of the two regulators are compared by comparator to output q-axis reference voltage u q ＝u q1 While d-axis current loop outputs d-axis reference voltage u d 。u d And u q Rotor position angle extracted according to phase-locked loop technique
Obtaining u of reference voltage under an alpha-beta coordinate system through Park inverse transformation α And u β ，u α And u β Obtaining variable u in three-phase stator coordinate system by Clarke inverse transformation (or space voltage vector modulation technology) A 、u B 、u C ，u A 、u B 、u C After the comparison and the drive circuit, a drive signal for controlling the on/off of a switching tube of the inverter is generated, thereby generating a stator current i of the three-phase motor for controlling the motion state of the motor A 、i B 、i C . Method for electrically charging motor stator by using current sensorThe stream is sampled and i is calculated by coordinate transformation α 、i β 、i d And i q . Wherein i d 、i q Current closed loop control is achieved as feedback current to the current regulator and u d And u q Together as the input of the back electromotive force real-time estimation module, the following calculation is carried out:
in the formula (3), the reaction mixture is,
for the rotational speed calculated for the phase-locked loop,
and
is the calculated back emf.
The back electromotive force calculation algorithm based on the synchronous rotating coordinate system implemented by the model shown in equation (3) can be represented by the functional block diagram shown in fig. 2. A first multiplier M1 is used for multiplying the motor current i under a d-q coordinate system d And the measured value R of the stator winding resistance s Performing multiplication operation, and outputting a product result to a first adder A1; the second multiplier M2 is used for multiplying the motor current i under the d-q coordinate system q And the measured value R of the stator winding resistance s Performing multiplication operation, and outputting a product result to a third adder A3; the third multiplier M3 actually energizes the motor winding with the angular frequency of the alternating current
And the measured value L of the quadrature axis inductance under the d-q coordinate system q Performing multiplication operation, and outputting a multiplication result to a fourth multiplier M4; the fourth multiplier pair carries out motor current i under a d-q coordinate system q Performing multiplication operation on the product output by the third multiplier and outputting a product result to a third adder A3; a fifth multiplier M5 for the motor current in d-q coordinate systemi d The result output by the third multiplier is subjected to multiplication operation, and the product result is output to a third adder A3; the first adder A1 carries out accumulation operation on the product result output by the first multiplier and the product result output by the fourth multiplier, and outputs the accumulation result to the second adder A2; the third adder A3 carries out accumulation operation on the product result output by the second multiplier and the product result output by the fifth multiplier, and outputs the accumulation result to the fourth adder A4; the second adder A2 adds the result of the first adder output and the voltage u in the d-q coordinate system d Performing accumulation operation to output the observed value of the extended back electromotive force under the d-q coordinate system
The fourth accumulator outputs the accumulation result to the third accumulator and the voltage u under the d-q coordinate system q Performing accumulation operation to output the observed value of the extended back electromotive force under the d-q coordinate system
It is clear from this algorithm that the current differential term in the conventional extended back emf is
Or
And differential errors and iterative operation are avoided, so that the estimation of the rotor position angle information is more accurate.
A schematic block diagram of the phase locked loop for speed/position estimation of the back emf information is shown in fig. 3-5. The functional block diagrams shown in fig. 3 to 5 represent 3 data processing strategies for back emf:
the first data processing strategy of back electromotive force is shown in fig. 3, which calculates the back electromotive force
By difference from a given reference value of 0, i.e.
As an input to the phase locked loop. The method only needs to be used
The information of this variable greatly simplifies the calculation, but has a problem that the calculation is performed at a low speed
Small fluctuation amplitude and high speed
The amplitude of the fluctuation is large, so that in the phase-locked loop K p 、K i Under the condition of parameter determination, the dynamic performance and the steady-state performance of the phase-locked loop in different speed domains have certain difference. The method is suitable for medium and low end electric driving scenes which have low requirements on control performance and have strict limits on the calculation force of the controller.
The second data processing strategy of back electromotive force is shown in fig. 4, which calculates the back electromotive force
Is divided by
Is then subtracted from a given reference value of 0, i.e.
As an input to the phase locked loop. The method is equivalent to an approximate normalization process, and when the back electromotive force calculates the value
When the phase-locked loop converges to be close to 0, the steady-state performance of the phase-locked loop in different speed domains is the same, and the dynamic performance is slightly different. Compared with the first method, the method has the advantages that the calculation amount is slightly increased, but the stability of the phase-locked loop is greatly improved, and the method has great engineering application advantages.
Data processing of a third kind of back emfThe strategy is to calculate the value of the back electromotive force as shown in FIG. 5
Divided by the magnitude of the back-emf and then differed from a given reference value of 0, i.e.
As an input to the phase locked loop. The method is a normalization process, and limits the input value of a phase-locked loop in any speed domain in a system without position control, including the starting process, between-1 and 0, so that the method ensures that the phase-locked loop has the same dynamic performance and steady-state performance under the condition of no position control in the full-speed domain, and is a scheme for ensuring the optimal stability of the control system. However, this method has the same computational complexity and no computational advantage compared to the quadrature phase-locked loop.
The phase-locked loop calculates the error between the estimated rotor position angle and the actual rotor position angle, and the error is subjected to proportional integral and then outputs the estimated rotating speed
Estimating rotational speed
Obtaining an estimated position angle through an integral link
Fig. 1 illustrates the operating principle of a parallel tacho current regulator. Different from the traditional double closed-loop control system, the output of the rotating speed loop is used as the input of the current loop, the output of the rotating speed loop and the output of the current loop are both used as the reference voltage of the motor by the parallel rotating speed current regulator, but only one of the rotating speed loop and the current loop is in an effective working state, and the other one of the rotating speed loop and the current loop is in a saturated state. The rotating speed ring rotates at a reference rotating speed omega ref And estimating the rotational speed
The difference is used as input, the current loop is rated with a rated current i qmax And a feedback current i q The difference is used as input. When the load on the motor is small, i corresponds to q Is also smaller when (i) qmax -i q )>0, after positive proportion and integration, outputting u q2 Is saturation clipped. To keep the speed constant, only u output in the speed loop is needed q1 As a reference voltage, u q1 <u q2 The speed loop is in an active operating state. When the load on the motor has been overloaded, the corresponding i q Will also be higher than the rated current i qmax At this time (i) qmax -i q )<0, the current loop begins to desaturate, and the rotating speed loop can ensure the constant rotating speed due to the fact that higher voltage is needed, so that the reference value u output by the rotating speed loop q2 Go to saturation limit value, at which time u q1 >u q2 The current loop is in an effective working state to limit the current to i qmax And nearby, overcurrent is avoided. Under the effective working state of a current loop, the position-free control system can be regarded as a single closed loop system, and the slight reduction of the rotating speed can cause the rapid current (also can be regarded as torque) compensation, so that the motor returns to a steady state before the rotating speed position estimation error is amplified, the phenomenon that the rotating speed is larger to fall due to the amplification of the position estimation error is avoided, and the strong robustness of the position-free control system is realized.
In order to verify the practical effectiveness of the invention, an experimental platform is built based on an STM32 digital controller for verification. The experimental motor is a three-phase 4-antipodal PMSM, and fig. 6 is an experimental waveform diagram of the motor which is increased from 0 speed to 100rpm by adopting a back electromotive force algorithm provided by the invention. Fig. 7 is a waveform diagram of an experiment in which the motor is raised from 100rpm to 200rpm using the back electromotive force algorithm proposed by the present invention. It can be seen from fig. 6 and 7 that, in the motor no-position starting process and the motor speed increasing process, the estimated position angle and the actual position angle keep the same phase, and although some rotational speed overshoot exists, the rotational speed waveform is relatively stable, which proves that the method has good reliability in the motor starting and the medium-low speed domain operation.
Fig. 8 shows an experimental waveform of the method of the present invention for ramping up and down in the full speed domain. It can be seen that the actual rotating speed waveform and the estimated rotating speed waveform are kept consistent, and the transient process is extremely short no matter the speed is increased or decreased, so that the dynamic response of the invention in the speed regulating process is good, and the actual rotating speed waveform and the estimated rotating speed waveform are stable.
Fig. 9 is an experimental waveform diagram of load disturbance at low speed using a conventional double closed loop and the proposed back emf method. The reference rotating speed is set to be 100rpm, the motor can be considered to work at a lower rotating speed, the load disturbance is suddenly applied to the motor within about 0.5s, the estimated rotating speed of the motor can be seen to drop remarkably, the estimated position angle is also distorted remarkably, the estimation error of the electrical angle is increased remarkably, and the situation that the traditional position-free control method is poor in load disturbance resistance in a low-speed domain and is very soft in mechanical characteristics is shown.
Fig. 10 is an experimental waveform diagram of load disturbance at low speed using the proposed parallel type tacho current regulator and the proposed back emf method of the present invention. The reference speed, again 100rpm, suddenly applied load disturbance to the motor at around 0.9s, it can be seen that the estimated speed of the motor has only slightly dropped and then quickly recovered, and there is no speed overshoot. The estimated position angle keeps consistent frequency with that under the steady state condition after sudden load disturbance, the angle estimation error is always limited to-0.05 rad, and the angle estimation error after loading is smaller.
The above description is only a preferred embodiment of the back emf observation algorithm based on the rotating coordinate system, and is not limited to the proposed back emf observation algorithm combined with the parallel type tacho current regulator, and the back emf algorithm can also be combined with the conventional dual closed-loop regulator to achieve the position-free control.
Claims (7)
1. A rotor information estimation method based on the observation of back electromotive force under dq axis is characterized in that,
acquiring components of motor stator voltage and stator current in a synchronous rotating coordinate system in real time, and observing components of counter electromotive force in the synchronous rotating coordinate system according to components of motor stator reference voltage and stator current in the synchronous rotating coordinate system and rotating speed estimated by a phase-locked loop;
and extracting input information of the phase-locked loop according to the component of the observed counter electromotive force in the synchronous rotating coordinate system.
2. The method for estimating rotor information based on the observation of the back electromotive force under the dq axis as claimed in claim 1, wherein the expression of observing the component of the back electromotive force under the synchronous rotating coordinate system according to the component of the reference voltage and the stator current of the motor under the synchronous rotating coordinate system and the rotating speed estimated by the phase-locked loop is as follows:
wherein,
and
d-axis component and q-axis component, u, of back electromotive force in a synchronous rotating coordinate system d And u q Respectively a d-axis component and a q-axis component of the voltage at the input end of the motor under a synchronous rotating coordinate system, R s For the stator winding resistance of the machine, L q The component of the stator inductance on the axis of the synchronous rotating coordinate system d q,
estimated rotation speed, i, for phase-locked loop d And i q The d-axis component and the q-axis component of the stator current in a synchronous rotating coordinate system are respectively.
3. The method for estimating rotor information based on back electromotive force observation under dq axis according to claim 1 or 2, wherein the specific method for extracting the input information of the phase-locked loop according to the component of the observed back electromotive force in the synchronous rotating coordinate system is:
taking the information obtained by subtracting the d-axis component of the reference value 0 and the counter electromotive force observation value in the synchronous rotating coordinate system as the input information of the phase-locked loop; or the like, or a combination thereof,
calculating the ratio of the amplitudes of the d-axis component and the q-axis component of the counter electromotive force observed value in a synchronous rotating coordinate system, and taking the information obtained by subtracting the reference value 0 from the ratio as the input information of the phase-locked loop; or the like, or a combination thereof,
and calculating a normalized value of the d-axis component of the observed value of the back electromotive force in a synchronous rotating coordinate system, and taking the information obtained by the difference between the reference value 0 and the normalized value as the input information of the phase-locked loop.
4. Rotor information observer based on counter electromotive force observation under dq axle, its characterized in that includes:
the counter electromotive force observer is used for receiving the collected values of the reference voltage of the motor stator and the component of the stator current in the synchronous rotating coordinate system, and observing the component of the counter electromotive force in the synchronous rotating coordinate system according to the component of the reference voltage of the motor stator and the component of the stator current in the synchronous rotating coordinate system and the rotating speed estimated by the phase-locked loop;
the input end of the phase-locked loop input quantity extraction module receives the component of the counter electromotive force output by the counter electromotive force observer in a synchronous rotating coordinate system and outputs the input information of the phase-locked loop; and a (C) and (D) and,
and the input end of the phase-locked loop is connected with the output end of the phase-locked loop input quantity extraction module, and a rotating speed estimation value and a rotor position estimation value are output.
5. The position-free control method of the three-phase permanent magnet synchronous motor is characterized in that the rotor information estimation method based on the dq-axis counter electromotive force observation in claim 1 is adopted to estimate the rotating speed and the rotor position, the rotating speed estimation value is sent to a rotating speed inner ring for closed-loop control, and the rotor position estimation value is sent to a current outer ring for closed-loop control.
6. The method of claim 5, wherein the q-axis component of the motor stator voltage in the synchronous rotating coordinate system is obtained by a parallel type tacho current regulator.
7. The position-free control method of the three-phase permanent magnet motor according to claim 6, wherein the specific method for obtaining the q-axis component of the motor stator voltage in the synchronous rotation coordinate system by adopting the parallel type rotating speed current regulator comprises the following steps:
when the load of the motor is not overloaded, the error between the estimated value of the rotating speed and the rated rotating speed is subjected to rotating speed regulation, and a q-axis component of the motor stator voltage under a synchronous rotating coordinate system is obtained;
when the motor load is overloaded, the current of the q-axis component of the motor stator current and the error of the rated motor stator current are regulated, and the q-axis component of the motor stator voltage under a synchronous rotating coordinate system is obtained.
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| CN116094394A (en) * | 2023-02-03 | 2023-05-09 | 北京中科昊芯科技有限公司 | Method, device, medium and electronic equipment for acquiring motor working parameter value |
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| CN116094394B (en) * | 2023-02-03 | 2024-03-22 | 北京中科昊芯科技有限公司 | Method, device, medium and electronic equipment for acquiring motor working parameter value |
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