TW439349B - Speed control method for induction motor - Google Patents

Abstract

The present invention relates to a speed control method for induction motor, especially about a speed-sensorless vector control method with high torque in a zero-speed region without the necessity of being installed in the motor. The present invention provides: a speed control method of induction motor which will not suffer from torque shortage even in a zero-speed region and which will not be affected by the speed estimation error due to the variation of motor constant. In the control method of the present invention, d axis current is controlled to stay above the normal value when the speed command is under the rated value. Also, the speed command value is used to replace the speed estimation value in computing the frequency command value. According to the present invention, torque shortage in the zero-speed region can be prevented for speed control of the induction motor.

Description

43 33 4 9 A7 B7 V. Description of the invention (Ί) [Technical field to which the invention belongs] The present invention relates to a method for controlling the speed of an induction motor ', and particularly to a speed sensor that does not need to be mounted on the motor, and can be obtained from the zero speed field. Speed sensorless vector control method for high torque. [Known technology] In vector control of induction motors, it is generally: the method of controlling the output frequency of the converter according to the sum of the rotation speed of the motor and the slip frequency reference. On the other hand, for speed sensorless vector control, speed estimation is used instead of actual rotation speed to control the output frequency. However, because the speed estimation 値 contains errors, the actual slip frequency will vary from an appropriate reference 値. At this time, the magnetic flux of the motor fluctuates (decreases) in response to the change in torque. As a result, the torque generated by the motor is not proportional to the torque current. In extreme cases, the torque may be insufficient. The reasons for the error in speed estimation are: the setting error of the motor constants (first and second resistance) used in the speed estimation calculation, and the change in the magnetic flux of the motor that occurs twice due to this. The Consumer Cooperatives of the Central Bureau of Standards of the Ministry of Economic Affairs of the People's Republic of China (please read the notes on the back ^ | ^ before filling this page) At zero speed, the torque may be insufficient. In addition, related literatures include: Aoshan and other "Effects and Compensation of Control Constant Setting Errors of Speed and Voltage Sensor Vector Control and Their Compensation" Electrical Theory D, 110, 4 4? (Flat 2-5) »This paper is applicable to China National Standards (CNS) A4 specification (210X297 mm) _4 _ Printed by the Shellfish Consumer Cooperative of the Central Standards Bureau of the Ministry of Economic Affairs 4 3 133 4 9 at B7 V. Description of the invention (2) [Objective] The purpose of the present invention is to provide: The speed control method of the induction motor will not be affected by the speed estimation error caused by the change of the motor constant, etc., even in the zero speed area. [Means for solving the problem] The present invention is characterized by controlling the d-axis current above the normal 値 when the speed command 値 is below 値, and using the speed estimation 値 instead of the frequency command 値 > According to the speed command 値Operation. [Embodiment] An embodiment of the present invention will be described with reference to the drawings. Fig. 1 shows a configuration example of a speed sensorless vector control device according to an embodiment of the present invention. 1 is an induction motor, 2 is a power converter that outputs an output voltage proportional to the voltage command 値 V! *, 3 is a converter that converts the converter output current iu, iw coordinates, calculates the d-axis and q-axis current id, iq coordinate conversion 4 is a speed estimator that calculates ωω at the operating speed based on the q-axis voltage command 値 and i Q, and 5 is the speed command corresponding to the speed command 値 ω: * deviation from the speed estimation 値 ω to output the Q-axis current command 値The speed controller of i Q 'has a limiter that restricts i Q * according to the id. 6 is a Q-axis current controller corresponding to iq * and iq with an output △ q, 7 is a slip frequency calculator based on iq * based on a calculated slip frequency reference 値 ^ s *, 8 is an addition ω, and 0 > s * to get signal ω: * adder '(please read the note on the back before filling out this page) 1. .1 m n. m-!,. 1 This paper standard is the General Chinese Storehouse Standard (CMS) A4 specification ί 2ί297 × 297 mm) -5-B7 V. Description of the invention (3) 9 is an output switcher that switches according to the size of the rotation speed, by: ^! * And the output of the function device 9 1 G a 1 The multiplier 9 2 is a multiplier 9 4 that multiplies ω " and the output G a 2 of the function 9 3, and an adder 95 that adds the outputs of the two multipliers. 1 〇 is the integral output frequency command 値 ω i ΐ from the switching circuit 9 + phase reference generator based on the output phase reference 値 Θ, 1 1 is the d-axis current command 値, by adding the current 値 △ id and the function The multiplier 1 1 2 that multiplies the output G a 3 by 1 1 1 and the delay circuit 1 1 3 that adds the reference current 値 id * to the multiplier output to output its primary delay 値 i. "》 1 2 is a d-axis current controller that outputs a signal △ d according to the deviation between id ** and id, 1 3 is based on id **, iq * and ω〆 * to calculate the d-axis and q-axis voltage reference 値, Vq * voltage calculator, 14 is the sum of the output V〆 and ZXd 値 ν, * is the phase calculator, 15 is the output V, and Aq is added 値 VqM phase calculator, 16 is the V dw * and V q * * coordinate conversion is the output converter output voltage command 输出 V 1 * (3 phase) coordinate converter. Printed by Shellfish Consumer Cooperation of the Central Bureau of Standards of the Ministry of Economic Affairs (please read the notes on the back before filling in this 1). The above 9 and 11 are the features of the present invention. The characteristics of the function device in 9,1 1 are as follows: the output G a 1 of the function device 9 1 is 0 when ωι * is close to zero, 1 is taken when the number is large, and the output Ga 2 of the function device 9 3 is reversed.値. That is, G a 1 and Ga 2 have a complementary relationship (number 1).

Gal + Ga2 = l ... (number 1) This paper scale is applicable to the Chinese national standard {CNS) A4 Zhuge (210X297 mm) _ β-A! Printed by the Consumer Cooperatives of the Central Standards Bureau of the Ministry of Economic Affairs A7 B7 V. Invention Explanation (4) 'Therefore, the output ω of the switch 9: * is given by (number 2). In this way, ω〆 * is consistent with ω * in the zero-speed domain, and ωi * outside. The increasing / decreasing domain of Ga 1, Ga 2 is to make the switch smoother. In this domain, 'take ω 1 * and ω r * as the intermediate 値 as ω 1 * * is output 11 ω, ** = ω ι * Gal + ω ^ Ga2 ... (Number 2) In addition, the output G a 3 of the function device 1 1 1 is 1 when ω / is close to zero, and the other is 0. As a result, 'i d ** and i d in the zero speed range are strengthened by the reference 値 i d * only Δ i d. Next, the operation of the entire system will be described. The constituent elements 1 to 7 '10, 12, 13, 14 to 16 are the same as the conventional speed sensorless vector control system. First, it will be briefly explained. In the speed sensorless vector control, the rotation speed is estimated based on the converter output voltage and output current, and it is fed back to the speed controller 5 for speed control. At the same time, 値 ω is calculated according to the speed and the slip frequency reference 値 ω s * Add them to control the converter output frequency. The difference from the well-known vector control with speed sensor is that the speed estimation is used instead of the speed detection by the speed sensor mounted on the motor. The basic operation is the same. In order to control the motor current i q, ι d in accordance with the Q-axis current command 値 ι * * and the d-axis current command i d * * from the speed controller 5, the converter must supply the necessary motor voltage for this purpose. Therefore, in the calculation of voltage, this paper is applicable to _China National Standard (CNS) A4 (210 X 297 mm) _ 7-(Please read the precautions on the back before filling this page)

A7 A7 Printed by the Consumer Cooperative of the Central Standards Bureau of the Ministry of Economic Affairs B7 V. Description of the Invention (5) Device 1 3 calculates the d-axis and Q-axis voltage reference 依据 according to the current command 値 id 'iq * and the frequency command ω〆 *. Vq *, which is used to control the converter output voltage. However, only in this case, due to the control error, the current id and iq do not agree with each command. 'Based on the Q-axis and d-axis current controllers 6, 12 and Ad, the correction voltage V q *, V d * To control so that iq, i cl are consistent with the instruction 値. In this way, the torque of the operating motor that performs the slip frequency control type vector control is controlled to be proportional to i Q +. Next, detailed operations of each constituent element will be described. The speed estimator 4 follows (numeral 3) to calculate 値 ω, at the operation speed. ω / = 1 / (1 + T〇〇L2 * / (M * 0! * '* L σ' id ^ -CR σ * + L σ * s) iq) .. (Number 3) Here, TQ s : Observation time constants Ls *, M *: 2nd order and magnetizing inductance (reference 値): 2nd order magnetic flux (reference 値) R σ *: Sum of 1st order and 2nd resistance (reference 値)

La *: Sum of primary and secondary leakage inductance (reference 値) ω:: converter output frequency (command 値) Figure 2 shows the calculation content of the speed estimator 4 based on (number 3). 4 1 is a motor model, showing the relationship between the motor's Q-axis voltage Vq (= vQ **), the induced electromotive force e q, and the current i q. The calculation principle is: eq is calculated according to the inverse model, and is calculated by dividing the reference magnetic flux, and calculated at the calculation speed. The paper size is applicable to 1 national standard (CNS) A4 Zhuge ~ T2] 0X29 * 7 mm) -8 · ^ ( (Read the notes on the back before filling in this page)

A7A3-9-3AS-V. Description of the invention (6) B7 値 ω r ύύ is used for control Λ is used at the same time as the feedback signal to speed controller 5 'is also used. This expression is shown in (Number 4). It is known that ω i * is originally used for the output frequency command. The output frequency of the converter is controlled. 00 r (ι) Printed by the Shellfish Consumer Cooperative of the Central Standards Bureau of the Ministry of Economic Affairs On the other hand, in the speed controller 5, the speed deviation ωι * -Q axis current command 値 i Q * is calculated in accordance with the speed deviation. The motor torque is basically proportional to i Q *, and ω / and ω make the speed control consistent. In order to make the motor torque proportional to i Q *, the conditions are as follows: The motor currents i q and i q * are the same, and the motor magnetic flux is maintained at a standard level. For this reason, it is necessary to control the motor current i d ′ i Q to be consistent with each command 値 id **, iQ *. Therefore, 'd-axis and q-axis current controllers 12 and 6 are provided. Although the motor voltage for each operating condition is shown in (number 5), the corresponding voltage V d *, v / is based on id **, id *, ω〆 * and the motor constant. (Number 6) is used. Obtained through pre-calculation. Perform this operation on the voltage calculator 1 3

Vd = r1id- ω iL ο iq V〇 = r 1 iq + ω iL σ id + ω i (M / L2) φ ... (number 5) This paper size applies to China National Standard (CNS) A4 specification (210X297 mm) ) .G. Printed by the Shellfish Consumer Cooperative of the Central Bureau of Standards of the Ministry of Economic Affairs 3 93 4 9 A7 B7 ___ V. Description of the invention (7) Here, r 1: primary resistance (actual 値) L σ: 1 and 2 Sum of leakage inductance (actual 値) L £, Μ: 2 times and magnetizing inductance (actual 値) Φ 2: 2. magnetic flux (actual 値)

Vd '= rrid **-ω i " L a * iq * ν / = ΓΐΊς * + ω. &Quot; La ^ id ^ + w. &Quot; (MVLO 0… (number 6) Here, * and * * mean The reference voltage / command voltage converter output voltage (motor voltage) is basically controlled in accordance with the 7 'and Vq *. However, if there is a control error, based on this only, the actual current id, i Q is not related to each command致 —Due to the d-axis and Q-axis current controllers 12 and 6, the signal Δ d ′ Aq corresponding to the current deviation is obtained, and the output voltage is corrected according to this, and the id and 1 q are controlled to be consistent with the command 値. The operation in common with the learner will be described next, which is directly related to the present invention. The ω obtained by the speed estimator 4 includes an estimation error. Therefore, the problem of insufficient torque occurs as described above. In the estimation The causes of the error include primary and secondary resistance temperature changes, and leakage inductance changes due to the saturation of the iron core of the motor. Especially in the zero speed field, torque reduction is likely to occur due to various reasons. The invention aims to prevent the reduction of torque in the zero speed field. In the field of speed, speed control is performed according to a principle different from the above. Below, the paper size is in accordance with China's national standard (CNS) A4 specification (210X297 mm) _ 1〇_ '-(Please read the precautions on the back before (Fill in this page) Order -4 9 a7 B7 V. Description of the invention (8) Explain its content. Torque reduction As mentioned above, although the speed estimation error is the cause, it can be analyzed in the following two ways. Because the speed estimation is based on the control frequency, the actual slip frequency changes due to the estimation error. Due to the estimation error, the torque current cannot be controlled due to the estimation error. Appropriate 値. Therefore, the present invention solves each of the following methods. In the zero speed field, the speed command 値 Ur # is used instead of the estimation 値 ω to calculate and output the frequency command 値 ω r. That is, in the zero speed field, by switching The converter 9 replaces the normal ω: *, selects wr * to output, and controls the converter output frequency according to the speed command 値 ω ^ 311. In the zero speed field, the d-axis current is controlled to be ratio The rule is always large. That is, in the d-axis current commander 1 1, the normal reference 値 id * is added to △ id to strengthen the control id. The motor generates the torque re when the conditions "1" and "2" are applicable. The relationship with the current I 1 is shown in (Number 7). Yin Fan, a consumer cooperative of the Central Standards Bureau of the Ministry of Economic Affairs (please read the precautions on the back before filling this page) τ e = k (6, j 5Τ2) / ( 1+ (ω sT〇2L · 2 ... (Equation 7) Here, k: proportionality constant ω s: slip frequency T 2: secondary time constant I i: the magnitude of the motor current This paper applies Chinese national standards (CNS) A4 specifications (2 丨 0X297 mm) -1 1-

V. Explanation of the invention (9) I! In a certain situation, when the motor torque r c is at ω s T 2 = ± 1, the maximum value 采用 is adopted, but from 0 to the middle, the slip frequency ω s changes. In this case, ω s is generated passively according to the change of the actual speed ω r to the converter output frequency ωι (= ω 『*). That is, in response to the increase / decrease of the load torque, τ e follows the load torque as the increase / decrease. As a result, the motor speed is maintained near ω, * (only the slip part is changed), and the speed is controlled in accordance with the speed command. Here, because the maximum torque of the motor must be equal to or greater than the maximum torque of the load, it is necessary to control I 1 in proportion to the maximum torque of the load or more. Therefore, i d or i Q is controlled to a predetermined value. Although this method also has a method of setting iq + to a predetermined value regardless of the speed deviation, in the zero speed field, the direction of the load torque is detected by ω, etc. It is difficult to be precise because i Q * The polarity setting. Therefore, the method of setting i d #! T !, which does not require polarity, is set to a predetermined value, which is applicable to the embodiment of FIG. 1. At this time, the ground is also explained in the above "2". The current command 値 id ** is set to the normal reference 値 id * plus Ai d, and the id (= I!) Is controlled to be proportional to the maximum load. Moments of Moment. Printed by the Consumer Cooperatives of the Central Standards Bureau of the Ministry of Economic Affairs (please read the precautions on the back before filling this page) In the field of zero speed, as described above, to control the output frequency and output current of the converter, the above [1] The problem of (2) is solved and the insufficient torque is eliminated. The output frequency is in the range of several Η z or more > The output of switch 9 is switched from + to 01+, and the speed estimation 推 0 r Λ is used for frequency control in the same way as in the conventional manner. In order to make the switching smooth, ω r * and ω i * are gradually switched to suppress the abrupt change of ω! * * Accompanying the switching. Function This paper size applies to Chinese National Standard (CNS) A4 specification (2) 0 × 297 mm) _ 12-Printed in cooperation with the shellfish consumer cooperation of the Central Bureau of Standards of the Ministry of Economic Affairs + .Λ., A7 B7 V. Description of the invention (ΊΟ) The increasing / decreasing characteristics of the outputs Ga 1 and Ga 2 of 9 1 and 9 3 are set for this purpose. In addition, the d-axis current commander 11 is provided with a delay circuit 1 1 3 in order to suppress a sudden change in i d. Also, in the state of strengthening id (zero speed range), 'i Q * must be limited so that the motor current I i does not exceed the rated value', and during this period, the accuracy decreases due to ω 'i Q $ 由For proper deviations, it is necessary to suppress i Q * to a prescribed value or slightly close to zero. In this embodiment, a method of following (number 8) 1 in accordance with i d to make the limit of Q * 値 i Q M A x variable is used. iqMAx = (Ii, 2-id2) (Equation 8) Here, I 1 *: Motor current setting 値 FIG. 3 shows another embodiment of the present invention. This is an example of a speed sensorless vector control device suitable for the method of obtaining the speed estimation 推 ω / based on the output of the Q-axis current controller 6 /. In the figure, 1 to 3, 5, 7, 9 to 14, 16 are the same as those in FIG. 1. 6-Outputs ω in response to the deviation between iq * and i Q, q-axis current controller, 8 'adder ω r' and 0 $ *, adder of output signal 01 * switch 9 and the above embodiment Similarly, according to the size, choose to output it. In the state in which ω 1 * is controlled by the conventional output according to the switch 9, it is considered that the output of the current controller 6 / is equivalent to ω: " and it operates in the same manner as the above embodiment, and it is very clear that the same effect can be obtained. . In the field of zero speed in the above embodiment, although the enhanced control id is based on the Chinese paper standard (CNS) A4 specification (2) 0 × 297 mm) _ 13 _ (Read the precautions on the back before filling in this page }

Printed by the Central Bureau of Standards, Ministry of Economic Affairs, Shellfish Consumer Cooperatives A7 __B7 V. The description of invention (11) stipulates that, but the torque in the zero speed field has both positive and negative directions. This method is applicable in non-constant circumstances. The reason is as previously stated. On the other hand, when the torque is only in one direction, the polarity of 1 Q * only needs to be set according to the torque direction. As in the above embodiment, instead of setting the id to a predetermined value 値 > Set iq * to the specified value (a value commensurate with the maximum load torque). Fig. 5 shows the structure of this embodiment. In the figure, 1 to 10, 12 to 16 of the constituent elements are the same as those in FIG. 1, and the operations are also the same. 1 7 is a switching circuit that switches the output iq * of the speed controller 5 and the set current 値 1 Q 0 in accordance with the size of the rotation speed. The switching circuit is based on: outputting a "1" signal in the zero speed field. The multiplier 1 7 1 for the external output signal “◦” is multiplied by i q0 and the multiplier 173 of the output Ga4 (0SGa4 guest 1) of the delay circuit 172 by the signal G a 5 (which has a complementary relationship to G a 4 ( = 1 -Ga4, 0 Yun Ga5Sl) and iq * multiplier 174, and add the output of the two multipliers to output the current command iq + # of the q-axis current controller 6 adder 1 7 5. The operations of these elements are as follows: As described above, the function device 1 71 outputs a signal of "1" in the zero speed field, and outputs a signal of "0" outside. The delay circuit 1 7 2 outputs a signal G a 4 which delays the follow-up of the signal once for smooth switching. In the field of zero speed, the reason why Ga4 is "1" and Ga 5 is "0" is that the operations of multipliers 1 7 3, 1 74 and adder 1 7 5 are output from the Q-axis current commander 17. Q 〇. Therefore, the paper size of China National Standards (CNS) A4 (210X297 mm) is applicable at zero speed.-14-(谙 Please read the notes on the back before filling this page) Order 4 3 93 a? ___________ Β7 V. Description of the invention (12) Nearby 'follows iq 0, iq is controlled, and a sufficient torque can be obtained (1 Q 0 is set to be commensurate with the maximum torque of the load). In addition, outside the zero-speed domain, on the contrary, following i q *, i q is controlled, and the operation becomes the same as that of a conventional person. As described above, in the zero-speed field, the converter output frequency is controlled in accordance with ω r *, or the motor current is controlled in accordance with the regulation 値 i Q 〇, and even these elements can obtain the same effects as the above-mentioned embodiment. The above-mentioned embodiment is provided with the speed controller 5 and is an example of a speed control method suitable for controlling the torque according to the output signal i Q * ′. However, the method without the speed controller is also applicable to the present invention to obtain the same effect. Fig. 6 shows the structure of this embodiment. In the figure, the constituent elements 1 to 3, 10 to 14, and 16 are the same elements as those in FIG. 1 "7 — to obtain the slip frequency reference 値 0! Based on the q-axis current 値 1 Q; * . Next, the operation of the entire system will be described. The frequency command 値 ω〆 * in the state outside the zero-speed field is output, and it is printed by (^ Shaft Consumer Cooperative of the Central Standards Bureau of the Ministry of Economy (read the precautions on the back before filling this page) 1 1, the reference 値 id * is output. At this time, the overall operation becomes the same as the conventional speed sensorless vector control system. That is, while controlling the output frequency of the converter, the voltage calculator 1 3 is based on The motor voltage required for id *, iq * and ω〆 * calculations controls the output voltage of the converter accordingly. As mentioned above, since the output voltage and frequency of the converter are controlled, similar to V / F control However, according to the voltage calculator 1 3, the internal voltage drop of the motor is compensated, and the selection of the induced electromotive force (motor flux) has become a regulation. As a result, this paper size can be applied to the Chinese National Standard (CNS) until the low-speed range. Α4 Specifications (210 × 7mm) -15-Duty Work Consumption Cooperation, Central Standards Bureau, Ministry of Economic Affairs 43 93 49 A7 B7 5. Explanation of the Invention (彳 3) The present invention is applicable to this situation. In the field of zero speed, the output ω r * 'and the d-axis current commander 11 is output at 1 d * plus the command 値 id * * of △ id to strengthen the control id. Based on this, the same as the above-mentioned embodiment, 'the frequency is controlled in accordance with the speed command, and the d-axis current control is made larger than usual. Therefore, the lack of torque in the zero-speed range is eliminated. So far, it is in the field of zero speed. The converter output frequency is controlled by the speed command ，. When the load torque is applied, the rotation speed of the motor ω r is ω / only the slip frequency is reduced by 0 降低. This compensation is shown in the figure. In the embodiment of 1, the current controller outputs d and AQ of the d-axis and q-axis are used to estimate the slip frequency in the zero speed area, which can be performed by adding the slip calculation to the frequency command. Figure 7 The structure of this embodiment is shown. In the example of the speed sensorless vector control device of FIG. 1, the slip compensation in the zero speed field is applied. In the figure, 1 to 16 are the same as those in FIG. 1. 18 uses the d-axis and q Axis current controller output Ad, a slip estimator that calculates the slip frequency in the speed domain with the output frequency command. 19 is the sum of the output signal ω r * and the output 8 of 1 8 ω s Λ ω ω * * * Adder. The output of switcher 9 is consistent with ω, +, and outside in the field of collar speed. The structure of slip estimator 18 is illustrated in Figure 8. It is input to slip estimator. The signal of 8 is multiplied by the speed of the motor. The electromotive force constant is 1 8 1. The multiplication result and the signal are input to the adder 1 8 2. Then the output signal of the signal Ad and the adder 1 8 2 is input. The paper size applies Chinese national standards. (CNS) A4 specifications (210X 297 feet) _ 16 (Please read the precautions on the back before filling this page) Order d 3 93 4 9 " A7 B7 V. Description of the invention (14) Enter the divider 1 8 3. The output signal of the divider 1 8 3 is multiplied by the reciprocal of the second time constant of the motor (1 / T 2 *) to output the signal ω s Λ. Next, the effect of the slip estimator 18 which is a characteristic of the structure of this embodiment will be described. The voltages of the d-axis and q-axis of the motor refer to + 値 and the voltages vd and V q of the d-axis and q-axis of the motor are expressed by (number 9) and (number 10) respectively.

Vd *, = rl * id **-6j i ** L o + A d V, " = rriq * + < y, * 'L ο' ίά ^ + ω / '(ΜΊΐι ^ Φ 2 < ι * + Δ q · (number 9) Vd = rlid-c * j iL σ iq-ω i (M / L2) 0 &

Vi ^ rliq-ω iL σ id-ω i (M / L2) 0 2,… (number 10) In the zero speed field, (9) and (10) are used to control the Q-axis current iq to ◦. id. r 1 = 0, and the second term of the same formula is smaller than the third term. For example, even if L σ * ping L σ, it can be ignored. From the relationship of (Eq. 9) = (10), the current controller output Ad of d-axis and Q-axis, △ (! Is expressed by (number 1 1). (Please read the precautions on the back before filling this page) △ d = (rl-rl) id- < yi (M / L2) 0 2〇ΔQ— it) l (M / L2) 0 2d-6J 1 (M / L2) 0 2d .. (number 1 1) Therefore, at the output of the d-axis current controller △ d, a speed electromotive force eq (= ωΐ (M / L2) 02q) caused by the q-axis magnetic flux 02q appears. ). On the other hand, in △ (! Plus the speed electromotive force reference 値 [ω! ** (Μ * This paper size applies the Chinese national standard (CNS> A4 specification (210X297mm) _ 17-丨 A7 B7 V. Description of the invention ( 15) / L 2 *) < / »2 d *], it is possible to obtain the speed electromotive force eu (M / L2) 02d) which is related to the d-axis magnetic flux of the motor 0 2 d ^ Also, as above, the control For 1 d: In the case where 値 and iq = 0 are specified, the relationship between the magnetic flux on the d and q axes < /) 2d and the slip frequency of the motor ^, is expressed by (number 12). ω S = 1 / T2 * (-0 2q / 0 2d) = l / T2 * (ed / e〇 ... (Equation 12) Here, by performing the operation expressed by (Equation 1 3), the motor can be calculated Slip frequency ω s Λ. Ω / = 1 / Τ2 * {Δ d / (A q + ω 2ί *)} · .. (Number 13) Add the signal ω s Λ obtained by (Number 1 3) to The speed command 値 ω r * and the control output frequency command 値 ^^ ** can compensate for the reduction of the rotation speed caused by the load torque > It can perform high-precision speed control. Printed by the Central Standards Bureau of the Ministry of Economic Affairs-Industrial and Consumer Cooperatives (Please read the precautions on the back before you fill in this X.) Can you replace the above-mentioned Ad, Z \ Q, subtract the resistance reference 値 r 1 · 1 d from the voltage command 値 Vu **, and find — (M / L2) 02q), subtract the non-interference reference 値 id ") from Vq **, add Φ 2 / 'to find e / (= ωι (M / L2) 02d), and enter fr into (14) Representation operation * can also calculate ω ,. This paper size applies to Chinese national standard (CNS> A4 specification (210X297 mm) -18-printed by the consumer cooperation of the Central Bureau of Standards of the Ministry of Economic Affairs, printed A7 B7 V. Description of the invention (16) l / Tsfej / eq)… (number 14) That is, the d, q-axis speed electromotive force (ed, eq) related to the secondary magnetic flux 0 2 d, ώ 2 q are detected by the voltage command ，, and the slip frequency ω s Λ is calculated according to the ratio. By using the operation 値 ω s Λ to correct (ω! * * = Ω r * + ω s Λ) frequency command 値, the decrease in rotation speed is compensated. FIG. 9 shows another embodiment of the present invention. This embodiment is an example of a speed sensorless vector control device that uses the output of the Q-axis current controller 6 > to obtain the speed estimation 値 ω /, and is suitable for slip compensation in the zero speed field. In the figure, 1 to 3, 5, 7, 9 to 14, 16, 19 are the same elements as those in FIG. 6 / is a q-axis current controller that outputs ω r 'in response to the deviation between i Q * and i Q, 8 > is an adder that adds ω / and ω s * to add the output signal ω〆, 1 8 —based on The slip estimator of Vq * and Ad with output ω sn = In this embodiment, the relationship between the q-axis voltage reference 値 = q-axis voltage (V q * = Vq), (the second line of the number 6) = ( The second line of the number 10), in the zero speed range, the Q-axis current iQ is controlled to be 0, i Q. R 1 = 0, and the second term of the same formula is smaller than the third term 'for example' even if L σ * Off L σ can be ignored. That is, V q * = E q (= ω! (U y L z) 0 2 d) is the same as the previous embodiment, and the slip frequency can be calculated based on the ratio of v Q * and △ d. The structure shown in 〇 can be calculated by ω s Λ 'using ω s Λ to correct (= + frequency command 値, the same operation as the above embodiment, it is very easy to obtain the same effect. This paper scale applies Chinese national standards ( CNS〉 Α4 Specification (210X297mm) · 19-'.U .. (Please read the notes on the back before filling out this page) -ZΠ ·. Order printed by the Consumers Cooperative of the Central Standards Bureau of the Ministry of Economic Affairs Λ7' B7 V. Explanation of the invention (17) FIG. 11 shows another embodiment of the present invention. This embodiment is a speed sensorless vector control device in the manner of obtaining the signal ω i " by the output of the Q-axis current controller 6 /, which is applicable An example of slip compensation in the zero speed range. In the figure, 1 to 3, 5, 7, 9 to 14 '16' 1_9 are the same as those in Fig. 7. 6 " Responds to the deviation between i Q * and i Q Q axis current controller of ω i *, 8 〃 is subtracted from ω s * from ω〆, and the speed estimation 値 ω r Λ is obtained. The subtractor of the feed speed controller 5 is a slip estimator that outputs ωBΛ according to Vq * and Ad. This embodiment is also the same as the embodiment of FIG. 9 and can calculate ω s with the configuration of FIG. 10 Λ, using ω s Λ to modify (ω α μ = ω, + ω s Α) the frequency command 値, the same operation as the above embodiment, it is very clear that the same effect can be obtained. Figure 12 shows the other of the present invention Embodiment. This embodiment is an example of applying slip compensation in the zero-speed field to a speed sensorless vector control device without a speed controller. In the figure, the constituent elements 1 to 3, 10 to 1, 4, 16 and Figure 7 shows the same elements. 7 'is a slip frequency calculator based on the q-axis current 値 i Q to obtain the slip frequency reference 値 0 5 +, 1 8 > is the slip output based on V q * and Ad Difference estimator. This embodiment is also the same as the embodiment of FIG. 11. The structure shown in FIG. 10 can be used to calculate ω, and ω can be used to modify = + frequency command 値. The same effect can be obtained. Up to the above embodiment, in the zero speed field, although the d Zhi i d and the current load torque is constant regardless of the control mode, but the present paper negative light applied China National Standard Scale (CNS> A4 size (210X297 mm) {Please note quarrel read back surface of the page and then fill $ item)

Printed by A7 B7, the Consumer Sample Cooperative of the Central Sample Bureau of the Ministry of Economic Affairs. 5. Description of the invention (18) When the load is reduced, the operating efficiency decreases. Here, 値 ω is calculated based on the calculated slip to modify the d-axis current command 値 i d * * to improve the operating efficiency at light loads. Figure 13 shows this embodiment. This embodiment 'is an example of the speed sensorless vector control device of FIG. 7 and the correction compensation of the d-axis current command 电流 is applied. In the figure, 1 to 10, 12 to 16, 18, and 19 are the same elements as those in FIG. 7. -The output signal ω of the slip estimator 18 is input to the function generator 1 1 5 in the d-axis current commander 1 1 /. In the function generator 1 1 5, ω〆 is used to calculate a d-axis current command proportional to the load torque to correct the gain. In the multiplier 1 16, the d-axis current command reference i d # and the output signal of the function generator 1 1 5 are input, and the output signal i d μ is calculated. Next, the effect brought about by the d-axis current commander 1 1 / which is a structural feature of the present invention will be described. In the field of zero speed, the control is id: when 値 and i Q = 0 are specified, the slip of the motor commensurate with the load torque can be estimated based on the ratio of the current controller output Ad, Δς of the d and q axes. Frequency ω s. Using this estimation, 値 ω s Λ can be calculated by performing the operation shown in (Number 1 5) ί, and the d-axis current command 値 I 〇id " = F (ω /) id ·· .. ( Number 15) However, F) is at ¢ 0 / = 0, F) 2 1 This paper is applicable to national standards (CNS) Λ4 Zhuzhaochang (210X ^ 75 ^ (Please read the precautions on the back before filling this page) )

Printed by the Employees' Cooperative of the Central Standards Bureau of the Ministry of Economic Affairs 439349 A7 B7 V. Description of the invention (19) .ω, > 1, F (ω,) > 1 is an arbitrary function. Use (number 1 5) to obtain the d-axis current command 値 id μ, without load (c ^ s ^ Qiid * = id 'under load (ω, > 0) id ** > id * according to the load torque ( The slip frequency estimation 値 ω,) 'd-axis current command 値 is corrected, which can improve the operating efficiency at light load. In this embodiment, although the id is directly corrected through the function F (ω /) **, but according to the function F (ω,) to modify Ai d shown in Figure 7, the results are the same. Figure 14 shows other embodiments of the present invention. This embodiment is based on the Q-axis current controller 6 / output to obtain the speed estimation 値 ω, the speed sensorless vector control device. It is an example of the correction compensation of the d-axis current command 图 中. In the figure > 1 ~ 3, 5, 6 ', 7, 8 ', 9 ~ 10' 12 ~ 14,16,18 ', 19 are the same elements as those in Fig. 9. 1 1 / It is a d-axis current commander corresponding to the signal ω s Λ to modify the signal id * *. This embodiment also Acting the same as the above embodiment, it is very clear that the same effect can be obtained. Fig. 15 shows other embodiments of the present invention. This embodiment is based on Q The output of the current controller 6 以 获得 to obtain the signal ω: * is a speed sensorless vector control device, which is an example of the correction and compensation of the d-axis current command 値. In the figure, 1 to 3, 5, 6 " > 7, 8 ", 9 ~ 10, 12 ~ 14 ', 16', 18 ', 19 are the same elements as those in Figure 11. 1 1 —Corresponds to the signal ω s Λ to modify the id-axis d-axis current commander This paper scale applies to China National Standard (CNS) A4 Specification (210X 297mm) -22- (Please read the note on the back before filling this page),? Τ 4 3 93 4 9 A7 B7 V. Description of the invention (2〇). The embodiment also operates in the same way as the above-mentioned embodiment, and it is very clear that the same effect can be obtained. (Please read the precautions on the back before filling out this page) Figure 16 shows other embodiments of the present invention. A speed sensorless vector control device with a speed controller is applied to the example of correction and compensation of the d-axis current command 。. In the figure, the constituent elements 1 to 3, 7 a, 10 to 14, 16, 18, 1 and FIG. 6 are Identical elements: 1 1 / Responds to the signal ω s Λ to modify the d-axis current command of id * * This embodiment also operates in the same manner as the above-mentioned embodiment, and it is very clear that the same effect can be obtained. [Effects of the Invention] According to the present invention, a torque shortage does not occur even in the zero speed field, and it can provide high precision and high accuracy. Speed control method for efficient induction motors [Simplified description on the drawing] Printed by the Consumer Cooperative of the Central Bureau of Standards of the Ministry of Economic Affairs Figure 1 shows an embodiment of the present invention, which is a control circuit configuration diagram of the speed control device of an induction motor. Fig. 2 is a diagram for explaining the calculation content of the speed estimator of the device of Fig. 1; Fig. 3 is a diagram showing another embodiment of the present invention, which is a control circuit configuration diagram of a speed control device of an induction motor. Fig. 4 is a block diagram showing a control circuit of a speed control device of an induction motor according to another embodiment of the present invention. This paper size applies Chinese National Standard (CNS) A4 specification (210X297 mm) -23-4 3 ^ 3 4 9; 7 4 3 ^ 3 4 9; 7 Printed by the Consumers ’Cooperative of the Central Standards Bureau of the Ministry of Economic Affairs Explanation (21) FIG. 5 shows another embodiment of the present invention, which is a configuration diagram of a control circuit of a speed control device of an induction motor. Fig. 6 shows another embodiment of the present invention, which is a configuration diagram of a control circuit of a speed control device of an induction motor. Fig. 7 shows another embodiment of the present invention, which is a configuration diagram of a control circuit of a speed control device of an induction motor. Fig. 8 is a diagram for explaining the calculation content of the slip estimator of the device of Fig. 7. Fig. 9 is a diagram showing another embodiment of the present invention, and is a control circuit configuration diagram of a speed control device of an induction motor. FIG. 10 is an explanatory diagram of the calculation contents of the slip estimator of the apparatus of FIG. 9. FIG. FIG. 11 shows another embodiment of the present invention, which is a control circuit configuration diagram of a speed control device of an induction motor. Fig. 12 is a diagram showing another embodiment of the present invention, which is a control circuit configuration diagram of a speed control device of an induction motor. Fig. 13 is a view showing another embodiment of the present invention, and is a control circuit configuration diagram of a speed control device of an induction motor. Fig. 14 is a view showing another embodiment of the present invention, and is a control circuit configuration diagram of a speed control device of an induction motor. Fig. 15 shows another embodiment of the present invention, which is a configuration diagram of a control circuit of a speed control device of an induction motor. Fig. 16 is a view showing another embodiment of the present invention, and is a control circuit configuration diagram of the speed control device of the induction motor: 1 machine. This paper size applies to China National Standard (CNS) Α4 size (210X 297 mm) _ 24 · < Please read the precautions on the back before filling this page)

, 1T A7 A7 Printed by the Consumer Cooperatives of the Central Standards Bureau of the Ministry of Economic Affairs B7 V. Description of invention (22) Comparison table of main components 1 Induction motor 2 Power converter 3, 16 coordinate converter 4 Speed estimator 5 Speed rrSt degree control. 6 q axis current controller 9 switch 1 1 d axis current commander 1 2 d axis current controller 1 3 voltage calculation BS 1 8. Slip estimator (please read the precautions on the back before filling this page) -The size of this paper is applicable to Chinese National Standard (CMS) A4 (2) × 297mm -25-

Claims (1)

A8. B8 C8 D8 6. Application for patent scope 1. A method for controlling the speed of an induction motor, which is a power converter with an induction motor driven, and outputs the Q-axis current in response to the deviation between the speed command 速度 and the speed estimation 値The speed controller of the command 値 and the current command 循 of the d-axis (equivalent to magnetic flux) of the rotating magnetic field coordinate system and the current command 値 of the Q-axis to control the induction of the current controller's output current of the power converter The speed control device of the electric motor is characterized in that when the speed command (or speed estimation) is lower than the specified value, the d-axis current is controlled to be higher than the normal value. 2. A speed control method of an induction motor, which is a power converter with an induction motor and a speed controller that outputs a q-axis current command in response to a deviation between the speed command and the speed estimation, and follows a rotating magnetic field. The current command 値 of the coordinate system (equivalent to the magnetic flux) and the current command 値 of the Q axis, in order to control the output current of the power converter, the speed control device of the induction motor is characterized by: speed In the case where the command or speed estimation is below the specified threshold, the current on the d-axis is controlled to be above the normal time, and the current on the Q-axis is controlled to be below the specified threshold. 3. The control method described in item 1 or 2 of the scope of patent application, wherein the above-mentioned q-axis current command 値 is set to zero. 4. A method for controlling the speed of an induction motor, comprising a power converter for driving the induction motor, and a speed controller that outputs a Q-axis current command in response to a deviation between the speed command and the speed estimation, and according to the rotating magnetic field coordinates The current command of the Q axis is used to control the speed of the induction motor of the current controller that controls the output current of the above-mentioned power converter. The paper size is applicable to China National Standard (CNS) A4 specification (210X297 mm) -26-(please first (Notes on the back of Min Du, please fill out this page again), Words-Printed by the Consumer Cooperatives of the Central Standards Bureau, Ministry of Economic Affairs Printed by ABCD Employee Consumer Cooperative of the Central Standards Bureau of the Ministry of Economic Affairs. 6. The scope of the patent application control device is characterized by the following: the speed command or speed estimation is below the specified threshold, and the control (1 axis current in 5 or more. A speed control method for an induction motor, which is a power controller with an induction motor that drives the induction motor and a speed controller that outputs the ci axis current command in response to the deviation between the speed command and the speed estimation. And a speed control device of an induction motor in accordance with a current command 値 of the rotating magnetic field coordinate system (equivalent to magnetic flux) and the current command Q of the Q axis to control the output current of the power converter, The characteristics are as follows: In the case where the speed command 値 or speed estimation 値 is below the specified ，, the speed command 値 is used instead of the speed estimation 运算 for the calculation of the frequency command 6. 6. A speed control method of an induction motor, which is a drive Power converter for induction motor, and speed command and speed response Calculate the deviation of 値, use the speed controller that outputs the Q-axis current command ，, and follow the current command d of the d-axis (equivalent to magnetic flux) of the rotating magnetic field coordinate system and the current command 値 of the Q-axis to control the above-mentioned power conversion The speed control device of the induction motor of the current controller of the controller's output current is characterized in that the speed command 値 or speed estimation 値 is below the specified 値, and the d-axis current is controlled above the normal exciting current 値, and In the calculation of the frequency command, the speed command is used instead of the speed estimation. 7. A speed control method of an induction motor is a power converter with an induction motor driven and the deviation between the speed command and the speed estimation according to the speed command The speed controller that outputs the q-axis current command 値 applies the Chinese national standard (CNS > A4 specification {210X297 mm) -27-(Please read the precautions on the back before filling this page) Printed by the Consumer Cooperative of the Central Bureau of Standards of the Ministry of Economic Affairs. A8 ^.: B8 C8 D8, the scope of patent application and the current command of the Q axis of the rotating magnetic field coordinate system, to control the output current of the power converter The speed control device of an induction motor is characterized in that when the speed command 値 or speed estimation 値 is below the specified ，, the Q axis current is controlled above the specified ，, and the speed command 运算 is used in the calculation of the frequency command 値Instead of speed estimation 値. 8. A control method of an induction motor, which is a current controller with a power converter driving the induction motor and a current command d of the d-axis of the rotating magnetic field coordinate system to control the output current of the converter, and The d-axis and Q-axis current detection (or instructions) and the above-mentioned converter output frequency command (to calculate the output voltage reference of the converter). The voltage calculator responds to the speed command to control the induction of the converter output frequency The speed control device of the electric motor is characterized in that the speed d-axis is controlled to be above the specified threshold when the speed command is below the specified threshold. 9. A control method of an induction motor, comprising a power converter for driving the induction motor, and a current controller that follows the current command to control the output current of the converter, and controls the power converter according to the speed command. The speed control device for an induction motor with an output frequency is characterized in that it calculates the slip frequency of the motor based on the voltage of the induction motor (calculated by the slip frequency of the motor), adds the slip frequency estimation to the speed command (see above), and it should be added. To control the output frequency of the above converter. 1 0. — A control method of an induction motor, which is a power converter with an induction motor and a current command 依 of the d-axis and Q-axis of the rotating magnetic field coordinate system to control the current control of the output current of the converter Controller, in accordance with the speed instruction to control the output of the above-mentioned power converter. The paper size applies to Chinese national standards (CNS> A4 specification (210 X 297 mm) -28-(Please read the precautions on the back before filling this page) k 'order A8 4 _ B8439349 g88 6. The speed control device of an induction motor with a frequency range of patent application, which is characterized by calculating the slip frequency of the induction motor based on the output of the current controller, and at the above speed The command 値 plus the slip frequency estimation 因 should be added to control the output frequency of the above converter. 1 1 · The speed control method of an induction motor as described in item 10 of the scope of patent application, where the slip frequency The calculation of 値 is based on the ratio of the output 値 of the d-axis current controller to the output 値 of the q-axis current controller. ^ Printed by the Shell Standard Consumer Cooperative of the Central Standards Bureau of the Ministry of Economic Affairs 12. If the patent application scope is 9 ~ 11, the control method of an induction motor is implemented under the above-mentioned speed instruction or speed '" '1 3. For the control method of the 9th machine in the scope of the patent application, where the current command 値 control is a regulation 1. 1 4. In the control method of the induction motor as described in the 10th scope of the patent application, where the d-axis current The command 値 control is prescribed and the q-axis current command 値 is controlled to zero. 1 5 .—A method for controlling an induction motor, which is a power converter with an induction motor driven, and follows the current command to control the output of the converter The current controller of the current, which is a speed control device for an induction motor that controls the output frequency of the above-mentioned power converter according to the speed command, is characterized by calculating the slip frequency of the motor based on the voltage of the above induction motor. Calculate slip frequency 値 'to correct the above current command. 1' Induction motor (please read the precautions on the back before (Write this page) Order 6 control methods for induction motors, one that has the drive to drive the size of this paper. Applicable to Chinese National Standard (CNS) A4 (210X297 mm) -29-ABCD Printed by the Central Standards Bureau of the Ministry of Economic Affairs 2. Patent application: Power converters for induction motors, and current controllers that follow the d-axis and CJ-axis current instructions of the rotating magnetic field coordinate system to control the output current of the converter, and speed instructions to control the power conversion. The speed control device of the induction motor with output frequency is characterized by calculating the slip frequency of the motor based on the voltage of the induction motor, and calculating the slip frequency based on the slip frequency to correct the current command. 17. The method for controlling an induction motor as described in item 16 of the scope of the patent application, wherein the calculation of the slip frequency is based on the output of the d-axis current controller and the output of the q-axis current controller. Compared to carry on. _ 1 8. If the method of controlling the induction motors in the scope of patent application No. 15 ~ 1 is implemented under the above-mentioned speed command (or speed estimation below the prescribed), it will be implemented. 19. The control method of the induction motor according to item 16 in the scope of the patent application, wherein the d-axis current command (calculated based on the slip frequency above) is modified, and the q-axis current command is controlled to zero. 2 0. A control method of an induction motor, which is a power converter with an induction motor and a current command 値 of the d-axis and Q-axis of the rotating magnetic field coordinate system to control the output current of the converter. And a voltage calculator that calculates the output voltage reference of the converter based on the current detection (or instructions) of the d-axis and q-axis and the output frequency command of the converter, and controls the power converter according to the speed command The speed control device of an induction motor with an output frequency is characterized in that the slippage frequency of the motor is calculated based on the output of the above-mentioned voltage calculator, and the size of the paper is applicable to China National Standard (CNS) A4 specifications (2) 0 × 297 mm ) -30-, / -_d .4-- • .j (Please read the notes on the back before filling this page) Order 13 93 4 9 8 7 1 20 208 AS B8 C8 D8 6. Scope of patent application Rate 値, add the slip frequency estimation 上述 ′ to the speed command 因 above and add 因 ′ to control the output frequency of the converter. 2 1. A method for controlling an induction motor, which is a current controller provided with a power converter driving the induction motor and a current command of the d-axis of the rotating magnetic field coordinate system to control the output current of the converter, and A voltage calculator based on the d-axis and Q-axis current detection 値 or instructions 转换 器 and the converter's output frequency instruction 値 'to calculate the converter's output voltage reference 因 according to the speed instruction to control the output frequency of the power converter The speed control device of an induction motor is characterized in that the slip frequency of the motor is calculated based on the output of the voltage calculator above, and is calculated based on the slip frequency to correct the current command on the d-axis. 2 2. If the method of controlling an induction motor of the scope of patent application Nos. 20 to 2 is used, the above slip frequency estimation operation is performed based on the output of the voltage calculator and the Q axis output. 2 3. If the method for controlling an induction motor in the scope of patent application Nos. 20 to 2 is implemented under the above-mentioned speed instruction (below the prescribed). Printed by the Employees' Cooperatives of the Central Standards Bureau of the Ministry of Economic Affairs (please read the note on the back before filling this page) This paper size applies to Chinese National Standard {CNS) A4 (210X297 mm) _ 31-