CN108616232B - Asynchronous motor rotating speed controller and asynchronous motor rotating speed control method - Google Patents
Asynchronous motor rotating speed controller and asynchronous motor rotating speed control method Download PDFInfo
- Publication number
- CN108616232B CN108616232B CN201810724440.XA CN201810724440A CN108616232B CN 108616232 B CN108616232 B CN 108616232B CN 201810724440 A CN201810724440 A CN 201810724440A CN 108616232 B CN108616232 B CN 108616232B
- Authority
- CN
- China
- Prior art keywords
- voltage
- driving voltage
- thyristor
- microprocessor
- circuit
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 238000000034 method Methods 0.000 title claims description 21
- 238000001514 detection method Methods 0.000 claims abstract description 56
- 238000004804 winding Methods 0.000 claims abstract description 34
- 230000000087 stabilizing effect Effects 0.000 claims description 7
- 230000007935 neutral effect Effects 0.000 claims description 3
- 230000001276 controlling effect Effects 0.000 abstract description 12
- 230000001105 regulatory effect Effects 0.000 abstract description 5
- 239000003990 capacitor Substances 0.000 description 18
- 230000008859 change Effects 0.000 description 3
- 238000004364 calculation method Methods 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 238000013459 approach Methods 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000005284 excitation Effects 0.000 description 1
- 230000010354 integration Effects 0.000 description 1
- 230000003993 interaction Effects 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 230000008092 positive effect Effects 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
- H02P23/00—Arrangements or methods for the control of AC motors characterised by a control method other than vector control
- H02P23/0004—Control strategies in general, e.g. linear type, e.g. P, PI, PID, using robust control
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
- H02P2207/00—Indexing scheme relating to controlling arrangements characterised by the type of motor
- H02P2207/01—Asynchronous machines
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Control Of Ac Motors In General (AREA)
Abstract
The speed controller comprises a driving voltage control circuit, a voltage detection circuit, a thyristor state detection circuit and a microprocessor; the driving voltage control circuit comprises a thyristor, and comprises a first switch circuit which is connected in series between an alternating current power supply and a motor winding; the voltage detection circuit is connected with the alternating current power supply in parallel and detects the instantaneous voltage of the alternating current power supply; the thyristor state detection circuit is respectively connected with two ends of the first switch circuit and used for detecting the on-off angle of the thyristor; the microprocessor is respectively connected with the driving voltage control circuit, the voltage detection circuit and the thyristor state detection circuit, and is used for receiving instantaneous voltage, switching-on and switching-off angles and controlling the switching-on and switching-off of the thyristor; the microprocessor stores a voltage-rotating speed correspondence table, searches a target driving voltage according to the target rotating speed, and calculates the on-off angle of the next speed regulating period by combining the driving voltage of the current speed regulating period obtained by the instantaneous voltage and the on-off angle of the current speed regulating period so as to control the on-off of the thyristor.
Description
Technical Field
The invention belongs to the technical field of asynchronous motor speed regulation, and particularly relates to an asynchronous motor rotating speed controller and an asynchronous motor rotating speed control method.
Background
The rotation speed control of the three-phase asynchronous motor mainly comprises three speed regulation modes of frequency conversion, pole change and slip change. The variable frequency speed regulation is to control the rotation speed of the motor by changing the frequency of the power supply voltage of the motor, and is the most direct and popular speed regulation mode at present. However, since the main control component is an IGBT and it is necessary to rectify and stabilize the voltage and then invert the voltage, the cost is high, the circuit is complicated, the failure rate is high, the CPU occupancy rate is high, and the like. The pole-changing speed regulation is realized by changing the stator pole pair number of the cage motor by changing the wiring mode of the stator winding, and has harder mechanical characteristics and good stability. However, it is a stepped speed regulation, and the step difference is large, and smooth speed regulation cannot be obtained. The slip ratio changing speed regulation comprises voltage regulation and speed regulation, wound motor rotor series resistance speed regulation and wound motor series speed regulation. The speed regulation modes of changing the characteristic curve of the motor such as rotor series resistance and series inductance, and the mechanical speed regulation modes of changing the transmission characteristics of the rotating speed such as excitation speed regulation have the defects of complex circuit, high cost, difficult maintenance and the like. The voltage and speed regulation is mainly realized by changing the voltages at two ends of a motor stator winding by a multi-stage transformer or a thyristor so as to change the rotation moment, thereby realizing a speed regulation mode for regulating the rotation speed.
The thyristor in the voltage and speed regulation belongs to a semi-control device and is commonly used in the field of soft start of motors, and the output is directly influenced by fluctuation of input voltage and load power factor because of poor control output precision, so that the speed regulation control precision of the motor is poor, and people are seldom concerned about the voltage and speed regulation control of the motor thyristor at present. However, the development of thyristors has been over half a century, the cost is low, the driving circuit is simple, and the advantages which are incomparable with the IGBT are provided especially in the high voltage field, the performance is reliable, and the requirement for controlling the whole CPU resource is also small.
Disclosure of Invention
The invention provides an asynchronous motor rotating speed controller and an asynchronous motor rotating speed control method, which improve the voltage and speed regulation precision of a thyristor, and have lower cost and lower CPU occupancy rate.
In order to solve the technical problems, the invention is realized by adopting the following technical scheme:
an asynchronous motor rotating speed controller comprises a motor winding, wherein the motor winding is connected with an alternating current power supply, and the asynchronous motor rotating speed controller comprises a driving voltage control circuit, a voltage detection circuit, a thyristor state detection circuit and a microprocessor;
the driving voltage control circuit comprises a thyristor, which comprises a first switch circuit; the first switch circuit is connected in series between the alternating current power supply and the motor winding, and controls the on-off of the alternating current power supply and the motor winding to enable the motor winding to load driving voltage;
the voltage detection circuit is respectively connected with a live wire and a zero wire of the alternating current power supply and detects the instantaneous voltage of the alternating current power supply;
the thyristor state detection circuit is respectively connected with two ends of the first switch circuit and used for detecting the on-off angle of the thyristor;
the microprocessor is respectively connected with the driving voltage control circuit, the voltage detection circuit and the thyristor state detection circuit, and is used for receiving the instantaneous voltage, the on-off angle and controlling the on-off of the thyristor; the microprocessor stores a voltage-rotating speed corresponding table of a plurality of driving voltage values corresponding to rotating speeds under specific loads, and searches the voltage-rotating speed corresponding table by a target rotating speed to obtain a target driving voltage; the microprocessor calculates the driving voltage of the current speed regulation period according to the instantaneous voltage and the on-off angle of the current speed regulation period, calculates the on-off angle of the next speed regulation period according to the driving voltage of the current speed regulation period and the target driving voltage, and controls the thyristor to be on-off to adjust the driving voltage of the next speed regulation period.
In order to enable the motor rotation speed to be fast and stable, the driving voltage and the target driving voltage in the current speed regulation period are calculated to obtain the target output voltage in the next speed regulation period through a PID control algorithm, and the on-off angle of the next speed regulation period is calculated from the target output voltage.
The alternating current power supply is a sine wave power supply, the effective values of the half cycles are equal, and the speed regulation period is one half of the period of the alternating current power supply in order to improve the speed regulation precision.
Preferably, the driving voltage values of the voltage-rotation speed correspondence table include 1000 driving voltage values, and each driving voltage value is in an arithmetic progression of taking 0 as a minimum value, taking the voltage effective value of the standard ac power supply as a maximum value, and taking 1 per mill of the voltage effective value of the standard ac power supply as a tolerance.
A specific circuit design as one of the voltage detection circuits, comprising:
a first current limiting resistor is arranged on the first electrode,
a voltage transformer comprising a primary coil and a secondary coil; the primary coil comprises a first end and a second end; the secondary coil comprises a third end and a fourth end; the primary coil is connected with the first current limiting resistor in series and then is respectively connected with a live wire and a zero wire of the alternating current power supply;
the rectifying circuit comprises a first input end, a second input end and a first output end; the first input end and the second input end are respectively connected with the third end and the fourth end; the first output end is connected with the microprocessor.
The thyristor state detection circuit comprises a second current limiting resistor, a rectifying and voltage stabilizing circuit, a controllable switching element and an output circuit; the controllable switch element comprises a fifth end and a sixth end; the rectifying and voltage stabilizing circuit comprises a third input end, a fourth input end and a second output end; one end of the second current limiting resistor is connected with the third input end, and the other end of the second current limiting resistor and the fourth input end of the second current limiting resistor are respectively connected with two ends of the first switch circuit; the second output end is connected with the second control end; the fifth end and the sixth end are respectively connected with the output circuit and the ground; the output circuit is connected with the microprocessor; when the first switch circuit is communicated, the output circuit outputs a low level to the microprocessor; when the first switch circuit is turned off, the output circuit outputs a high level to the microprocessor.
An asynchronous motor rotating speed control method applied to the asynchronous motor rotating speed controller comprises a motor winding, wherein the motor winding is connected with an alternating current power supply; the asynchronous motor rotating speed controller comprises a driving voltage control circuit, a voltage detection circuit, a thyristor state detection circuit and a microprocessor; the microprocessor is respectively connected with the driving voltage control circuit, the voltage detection circuit and the thyristor state detection circuit; the driving voltage control circuit comprises a thyristor, which comprises a first switch circuit; the first switch circuit is connected in series between the motor winding and the alternating current power supply; the voltage detection circuit is respectively connected with a live wire and a zero wire of the alternating current power supply; the thyristor state detection circuit is respectively connected with two ends of the first switch circuit; the method for controlling the rotating speed of the asynchronous motor comprises the following steps:
s1: measuring the rotating speeds of the asynchronous motor under a specific load and a plurality of driving voltage values to form a voltage-rotating speed correspondence table;
s2: storing the voltage-speed correspondence table into the microprocessor;
s3: the microprocessor inquires the voltage-rotating speed correspondence table according to the target rotating speed to obtain a target driving voltage corresponding to the target rotating speed;
s4: the microprocessor receives the instantaneous voltage output by the voltage detection circuit and the on-off angle of the thyristor detected by the thyristor state detection circuit;
s5: the microprocessor calculates the driving voltage of the current speed regulation period according to the instantaneous voltage of the current speed regulation period and the on-off angle of the current speed regulation period;
s6: the microprocessor calculates the target output voltage of the next speed regulation period according to the driving voltage of the current speed regulation period and the target driving voltage;
s7: the microprocessor calculates the on-off angle of the next speed regulation period according to the target output voltage;
s8: the microprocessor controls the on-off of the thyristor to provide the driving voltage of the next speed regulation period according to the on-off angle of the next speed regulation period;
and (3) repeating the steps S3-S8, and adjusting the rotating speed of the asynchronous motor in real time.
In order to enable the motor rotation speed to be stable rapidly, the microprocessor calculates the target output voltage of the next speed regulation period by a PID control algorithm according to the driving voltage of the current speed regulation period and the target driving voltage, and calculates the on-off angle of the next speed regulation period by the target output voltage of the next speed regulation period.
The alternating current power supply is a sine wave power supply, the effective values of the half cycles of the alternating current power supply are equal, so that the speed regulation precision is improved, and the speed regulation period is one half of the period of the alternating current power supply.
Preferably, each driving voltage value in the voltage-rotation speed correspondence table is in an arithmetic progression with 0 as a minimum value, 1%o of the voltage effective value of the standard ac power supply as a maximum value, and the voltage effective value of the standard ac power supply as a tolerance.
Compared with the prior art, the invention has the advantages and positive effects that: according to the asynchronous motor rotating speed controller and the asynchronous motor rotating speed control method, the thyristor which is mature in technology and low in cost is used for controlling the voltage applied to the motor stator winding, and the voltage is adjusted through a real-time tracking method, so that the rotating speed of the motor is accurately controlled, the cost is low, and the occupancy rate of a CPU is low.
Drawings
FIG. 1 is a block diagram of an embodiment of an asynchronous motor speed controller according to the present invention;
FIG. 2 is a flow chart of an embodiment of a method for controlling the rotational speed of an asynchronous motor according to the present invention;
FIG. 3 is a schematic diagram of waveforms of voltage and current across stator windings of an asynchronous motor;
FIG. 4 is a drive voltage control circuit;
FIG. 5 is a voltage detection circuit;
FIG. 6 is a thyristor state detection circuit;
fig. 7 is a power supply and zero crossing detection circuit.
In the drawing the view of the figure,
w1, an alternating current power supply W phase; v1, an alternating current power supply V phase; u1, an alternating current power supply U phase; n1, an alternating current power supply zero line; PE, ground wire; w1', motor drive voltage W is connected to the access terminal; v1', motor drive voltage V is connected to the end; u1', motor drive voltage U is connected to the end;
1. a driving voltage control circuit; 2. a voltage detection circuit; 3. a thyristor state detection circuit; 4. a microprocessor;
q001, thyristor; 001. a first switching circuit; 002. a first control end; CTRL_U and a microprocessor thyristor control interface; CN001, motor terminal;
r101, a first current limiting resistor; t101, a voltage transformer; d101, a rectifying circuit; c101, decoupling capacitor; CN101, AC power supply access end; V-AC, AD interface; 101. a first end; 102. a second end; 103. a third end; 104. a fourth end; 105. a first input; 106. a second input terminal; 107. a first output terminal;
r201, a second current limiting resistor; r202 is a first resistor; r203, second resistance; r204, third resistance; r205, fourth resistance; r206, fifth resistance; d201, rectifying and stabilizing circuit; d202, a first diode; d203, a second diode; d204, a third diode; c201, a first capacitor; c202, a second capacitor; c203, a third capacitor; q201, controllable switching element; s201, an output circuit; a PC201, a photocoupler; uon, a thyristor on-off signal receiving interface; 201. a third input; 202. a fourth input; 203. a second output terminal; 204. a second control end; 205. a fifth end; 206. a sixth end; 207. a low voltage power supply circuit;
t301, step-down transformer; RN, corresponding zero line end; RL, corresponding fire wire end; PC302, voltage comparator; zero_r, ac power ZERO signal interface; r302 is a first voltage dividing resistor; r303, a second voltage dividing resistor; r304 is a third voltage dividing resistor; r305, pull-up resistor; r306, a third current limiting resistor; and C306, a fourth capacitor.
Detailed Description
Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals refer to the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by referring to the drawings are illustrative and intended to explain the present invention and should not be construed as limiting the invention.
The asynchronous motor comprises a stator winding, and two ends of the stator winding are connected with a live wire and a zero wire of an alternating current power supply. Referring to fig. 1, 2, 3, 4, 5 and 6, an asynchronous motor rotational speed controller includes a driving voltage control circuit 1, a voltage detection circuit 2, a thyristor state detection circuit 3, and a microprocessor 4. The driving voltage control circuit 1 includes a thyristor Q001, and the thyristor Q001 includes a first switch circuit 001 and a first control terminal 002. The first switch circuit 001 is connected in series between the stator winding and the live wire of the ac power supply, and is used for controlling the on-off of the ac power supply and the stator winding, thereby controlling the driving voltage loaded on the stator winding and further controlling the motor rotation speed. The first control end 002 is communicated with the microprocessor 4, and the microprocessor 4 outputs a control signal to control the on-off of the first switch circuit 001. The voltage detection circuit 2 is connected to the live line and the neutral line of the ac power supply, respectively, and detects the instantaneous voltage of the ac power supply. The thyristor state detection circuit 3 is connected to both ends of the first switch circuit 001, respectively, and detects the on-off angle of the first switch circuit 001. The microprocessor 4 stores a voltage-rotation speed correspondence table of a plurality of driving voltage values between 0 and the voltage effective value of the standard ac power source and corresponding rotation speeds of the asynchronous motor under specific loads. And if the number of the driving voltage values in the voltage-rotating speed correspondence table is enough, forming a voltage-rotating speed correspondence curve. The microprocessor 4 is respectively connected with the voltage detection circuit 2 and the thyristor state detection circuit 3, receives the instantaneous voltage signal of the voltage detection circuit 2 and the signal of the on-off angle of the first switch circuit 001, and calculates the driving voltage at two ends of the stator winding in one speed regulation period through integration. When the microprocessor 4 receives the control command of the target rotation speed, the voltage-rotation speed correspondence table is queried to obtain the driving voltage corresponding to the target rotation speed, namely the target driving voltage. The microprocessor 4 calculates the conducting angle of the thyristor Q001 in the next speed regulation period through a control algorithm according to the target driving voltage and the driving voltage in the current speed regulation period, and controls the on-off of the thyristor Q001, so that the driving voltage is applied to the stator winding. Similarly, the on-off angle of the thyristor Q001 in the next speed regulation period is calculated by the microprocessor 4 from the driving voltage and the target driving voltage in the next speed regulation period through a control algorithm. And the driving voltage is regulated in real time in each speed regulation period, so that the driving voltage is infinitely close to the target driving voltage, and the motor rotating speed is accurately controlled. The cost is lower, the occupancy rate of the microprocessor is reduced, and the efficiency of the microprocessor is improved.
The method for controlling the rotating speed of the asynchronous motor is implemented on a rotating speed controller of the asynchronous motor, and comprises the following steps, referring to fig. 2.
S1: the method for testing the rotating speed of the asynchronous motor under a specific load by uniformly dividing the effective value of the standard alternating voltage into a plurality of voltage points is used as the driving voltage of the asynchronous motor to obtain a voltage-rotating speed correspondence table. If the number of voltage points is set to be enough, a voltage-rotating speed corresponding curve is formed.
S2: the voltage-rotation speed map is stored in the microprocessor 4.
S3: when the microprocessor 4 receives the rotation speed control command of the target rotation speed, the value of the target driving voltage corresponding to the target rotation speed is searched in the voltage-rotation speed correspondence table.
S4: the microprocessor 4 receives the instantaneous voltage output by the voltage detection circuit 2 and the on-off angle of the thyristor Q001 detected by the thyristor state detection circuit 3;
s5: the instantaneous voltage of the alternating current power supply tested by the voltage detection circuit 2 received in the current speed regulation period and the on-off angle of the thyristor Q001 detected by the thyristor state detection circuit 3 received in the current speed regulation period are integrated to calculate the driving voltage at two ends of the stator winding in the current speed regulation period.
S6: the microprocessor 4 calculates the target output voltage of the next speed regulation period through a control algorithm according to the target driving voltage and the driving voltage of the current speed regulation period;
s7: calculating the on-off angle of the thyristor Q001 according to the target output voltage;
s8: the on-off control is carried out on the thyristor Q001 according to the on-off angle of the thyristor Q001 so as to adjust the driving voltage of the next speed regulation period to enable the driving voltage to be close to the value of the target driving voltage.
And repeating S3-S8, and calculating the value of the target output voltage of the next speed regulation period by the microprocessor 4 from the target driving voltage and the driving voltage of the next speed regulation period by a control algorithm. The circulation control is performed in such a way that the control of the rotating speed of the asynchronous motor forms real-time tracking control, so that the driving voltage at two ends of the stator winding approaches the value of the target driving voltage infinitely. The method realizes the accurate control of the rotating speed of the asynchronous motor, and has lower cost and less occupied microprocessor resources.
In the above-described speed controller of an asynchronous motor and speed control method of an asynchronous motor, since the effective values of the voltages of the positive half cycle and the negative half cycle in one cycle of the ac power supply are equal, the above-described speed regulation cycle is set to one half of the cycle of the ac power supply.
In order to enable the rotating speed of the asynchronous motor to be fast close to the target rotating speed and stable, the microprocessor 4 obtains the target output voltage of the next speed regulation period through a PID control algorithm by using the target driving voltage and the driving voltage of the last speed regulation period, and then calculates the on-off angle of the thyristor Q001, so that the on-off of the thyristor Q001 is controlled, the driving voltage at two ends of the stator winding is fast close to the value of the target driving voltage, and the purpose of accurate control of the rotating speed is achieved.
Preferably, each driving voltage of the voltage-rotation speed correspondence table is in an arithmetic progression with 0 as a minimum value, 220V as a maximum value, and 1 ∈220V as a tolerance.
In a specific embodiment, referring to fig. 2 and 3, a method for calculating an effective value of a driving voltage across a stator winding is specifically as follows. Since the current of the ac power supply has a phase angle that lags the voltage of the ac power supply in the stator winding, the conduction angle of the thyristor Q001 is distributed on both sides of the zero point of the ac power supply voltage, which is defined as t1 and t2, respectively. The magnitude of t1, t2 is determined by the thyristor state detection circuit 3, and t2 is the phase angle of the lag. In order to reduce the operation pressure of the microprocessor 4 and improve the operation efficiency, an angle-voltage correspondence table of effective values at standard AC power supply voltages corresponding to a plurality of points of 0 to pi of the sine half cycle is stored in the microprocessor 4. Preferably, each point is in an arithmetic progression with 0 as the minimum, pi as the maximum, and 1%pi as the tolerance. And finding the effective values Vt1 and Vt2 of the standard alternating current power supply voltage according to the conduction angles t1 and t2 and finding the angle-voltage correspondence table, wherein the effective value of the driving voltage loaded to the two ends of the stator winding under the standard alternating current power supply is Vt=Vt1+Vt2. The effective voltage value of the integral sine half-cycle alternating current power supply is U RMS ' the effective voltage value of the standard alternating current power supply is U RMS The effective value of the voltage is calculated according to the formula:
the calculation formula of the effective voltage value under the conduction angles of t1 and t2 is as follows:
U m is the maximum value of the alternating current power supply,
it can be seen from the above that the effective value of the voltage is related to the conduction angle and the effective value of the ac power source, then,
Vt′＝Vt*U RMS ′ 2 /U RMS 2
v t' is the drive voltage across the stator windings for one cycle of speed regulation;
vt is an effective value of the standard alternating current power supply with the conduction angles of t1 and t 2;
U RMS ' is the effective value of the alternating current power supply for one speed regulation period;
U RMS is the effective value of the standard alternating current power supply.
And (5) carrying out PID control algorithm operation on the effective value V t' of the driving voltage in the current speed regulation period and the target driving voltage. The PID adopts a discrete increment type PID algorithm, and each increment calculation formula is as follows:
△u[n]＝K p {e[n]-e[n-1]}+K i e[n]+K d {e[n]-2e[n-1]+e[n-2]}
then uout=u [ n-1] +Δu
Δu: this PID increment;
kp: a scaling factor;
ki: an integral coefficient;
kd: a differential coefficient;
e [ n ]: the current voltage error value is the difference between the driving voltage of the current speed regulation period and the target driving voltage;
e [ n-1]: the voltage error value of the previous speed regulation period is the difference between the driving voltage of the previous speed regulation period and the target driving voltage;
e [ n-2]: the voltage error value of the upper speed regulation period is the difference between the driving voltage of the upper speed regulation period and the target driving voltage;
uout: a target output voltage;
u [ n-1]: the target output voltage of the last speed regulation period;
the target output voltage of the speed regulation period is obtained after the on-off of the thyristor Q001 is calculated and controlled through PID, and the following formula is adopted:
V out /U RMS 2 ＝Uout/U RMS ' 2 the product can be obtained by the method,
V out ＝Uout×U RMS 2 /U RMS ' 2
vout is the output voltage of the standard AC power supply corresponding to the target number voltage. The effective value of the standard alternating current power supply is set into a plurality of points, the corresponding value of 0-pi is calculated, and a voltage-conduction angle corresponding table is formed and stored in the microprocessor 4. Preferably, each point is in an arithmetic progression with 0 minimum, 220V maximum, and 1%220 tolerance. And searching the conduction angle of the thyristor Q001 corresponding to the Vout from the voltage-conduction angle corresponding table, then corresponding 0-pi to sine half-cycle time, calculating the specific moment of conduction of the thyristor Q001, controlling the conduction of the thyristor Q001, and realizing the accurate control of the driving voltage.
The embodiments of the present invention will be described by taking a three-phase asynchronous motor as an example, and referring to fig. 1, 3, 4, 5, 6 and 7, CN001 is a motor terminal, and CN101 is an ac power supply access terminal. The method comprises the following steps: w1 is the W phase of an alternating current power supply; v1 is the V phase of an alternating current power supply; u1 is an alternating current power supply U phase; n1 is an alternating current power supply zero line; PE is a ground wire; w1' is the motor driving voltage W and is connected to the end; v1' is the motor driving voltage V and is connected with the end; u1' is the motor driving voltage U and is connected with the end; the invention will be described with reference to a U-phase power supply of a three-phase ac power supply, a zero line N1 and a U-phase power supply of a three-phase asynchronous motor. In addition, the microprocessor comprises a microprocessor thyristor control interface CTRL_ U, AD interface V-AC, a thyristor on-off signal receiving interface Uon and an alternating current power supply ZERO signal interface ZERO_R.
Referring to fig. 5, the voltage detection circuit 2 includes a first current limiting resistor R101, a voltage transformer T101, and a rectifying circuit D101. The voltage transformer T101 is a current-type voltage transformer, and includes a primary coil and a secondary coil. The primary coil comprises a first end 101, a second end 102. The secondary coil includes a third end 103 and a fourth end 104. The rectifying circuit D101 includes a first input terminal 105, a second input terminal 106, and a first output terminal 107. The first end 101 and the second end 102 of the primary coil of the voltage transformer T101 are connected to the U-phase U1 and the neutral line N1 of the ac power supply, respectively. The first current limiting resistor R101 is connected in series in the connection of the primary coil to the ac power supply. The third terminal 103 and the fourth terminal 104 are respectively connected to the first input terminal 105 and the second input terminal 106, the first output terminal 107 is connected to the AD interface V-AC of the microprocessor 4, and the instantaneous voltage of the U-phase of the AC power supply at each moment is detected. The AD interface V-AC of the microprocessor 4 is connected with the ground of the signal power supply 3.3V through a decoupling capacitor C101.
Referring to fig. 6, the thyristor state detection circuit 3 includes a second current limiting resistor R201, a rectifying and voltage stabilizing circuit D201, a first resistor R202, a controllable switching element Q201, and an output circuit S201. The rectifying and voltage stabilizing circuit D201 includes a third input terminal 201, a fourth input terminal 202, and a second output terminal 203. The controllable switching element Q201 includes a second switching circuit and a second control terminal 204. The second switching circuit includes a fifth terminal 205, a sixth terminal 206. Both ends of the second current limiting resistor R201 are connected to one end of the first switch circuit 001 and the third input terminal 201, respectively. The fourth input terminal 202 is connected to the other end of the first switch circuit 001. The second output terminal 203 is connected to one end of the first resistor R202, and the other end of the first resistor R202 is connected to the second control terminal 204. The output circuit S201 is connected to the fifth terminal 205, the thyristor on-off signal receiving interface Uon of the microprocessor 4, respectively. The sixth end 206 is grounded. When the first switch circuit 001 is connected, the output circuit S201 outputs a low level to the thyristor on-off signal receiving interface Uon of the microprocessor 4; when the first switch circuit 001 is turned off, the output circuit S201 outputs a high level to the thyristor on-off signal receiving interface Uon of the microprocessor 4. The microprocessor 4 calculates the driving voltage loaded at two ends of the stator winding in the current speed regulation period according to the received instantaneous voltage of the U phase U1 of the alternating current power supply in the current speed regulation period and the received on-off angle of the thyristor Q001.
Referring to fig. 6, the controllable switching element Q201 is preferably an NPN transistor including a base B, a collector C, and an emitter E. The second output terminal 203 is connected to the base B through the first resistor R202, the output circuit S201 is connected to the collector C, and the emitter E is grounded.
Referring to fig. 6, the output circuit S201 preferably includes a fast photo coupler PC201, a second resistor R203, a third resistor R204, a fourth resistor R205, a first diode D202, and a first capacitor C201. The light emitting diode circuit of the fast photocoupler PC201 is connected in series with the second resistor R203 and then connected in series between the collector C and the positive electrode of the low voltage power supply 5V'. The triode circuit part is respectively connected with the positive electrode of the signal power supply 5V and the ground and is connected with a thyristor on-off signal receiving interface Uon of the microprocessor through a third resistor R204. The thyristor on-off signal receiving interface Uon is grounded through a parallel circuit of the fourth resistor R205 and the first capacitor C201, and is connected with the positive electrode of the signal power supply 3.3V through the first diode D202, and the positive electrode of the first diode D202 is connected with the thyristor on-off signal receiving interface Uon, and the negative electrode is connected with the positive electrode of the signal power supply 3.3V. The alternating current circuit and the signal circuit are isolated through the rapid optical coupler of the output circuit S201, so that the interference of the alternating current circuit on the signal circuit is avoided. The third resistor R204, the fourth resistor R205 and the first diode D202 ensure that the thyristor on-off signal receiving interface Uon receives standard high and low levels.
Referring to fig. 6, the low-voltage power supply 5V' described above is obtained by the low-voltage power supply circuit 207. The low-voltage power supply circuit 207 includes a fifth resistor R206, a second diode D203, a third diode D204, a second capacitor C202, and a third capacitor C203. One end of the fifth resistor R206 is connected to the zero line N1, the other end is connected to the positive electrode of the second diode D203, and the negative electrode of the second diode D203 is connected to the negative electrode of the third diode D204, the positive electrode of the second capacitor C202, and one end of the third capacitor C203. The negative electrode of the third diode D204 is connected to the negative electrode of the second capacitor C202 and the other end of the third capacitor C203, and then grounded. The fifth resistor R206 acts as a current limiter, the second diode D203 acts as a half-wave rectifier, and the third diode D204 is a zener diode, which together with the second capacitor C202 and the third capacitor C203 stabilizes the output of the low voltage power supply 5V'.
In addition, the invention also comprises a zero-crossing detection circuit, and the invention is referenced to fig. 7. The voltage-limiting circuit comprises a step-down transformer T301, a voltage comparator PC302, a first voltage dividing resistor R302, a second voltage dividing resistor R303, a third voltage dividing resistor R304, a pull-up resistor R305, a third current-limiting resistor R306 and a fourth capacitor C306. The two ends of the primary coil of the step-down transformer T301 are respectively connected with the U-phase U1 and the zero line N1 of the alternating current power supply, the output end of the secondary coil comprises a corresponding fire wire end RL and a corresponding zero line end RN, and the voltage directions of the primary coil and the zero line end RN are respectively the same as the U-phase U1 and the zero line N1. The first voltage dividing resistor R302, the second voltage dividing resistor R303 and the third voltage dividing resistor R304 are connected in series, and the third voltage dividing resistor R304 is located between the first voltage dividing resistor R302 and the second voltage dividing resistor R303. One end of the first voltage dividing resistor R302 of the series circuit of the first voltage dividing resistor R302, the second voltage dividing resistor R303, and the third voltage dividing resistor R304 is connected to the corresponding zero line terminal RN, and one end of the second voltage dividing resistor R303 is connected to the corresponding fire line terminal RL. The voltage comparator PC302 includes a positive voltage input, a negative voltage input, and an output. The positive voltage input end and the negative voltage input end are respectively connected to two ends of the third voltage dividing resistor R304, the positive voltage input end is connected with a common end of the second voltage dividing resistor R303 and the third voltage dividing resistor R304, and the negative voltage input end is connected with a common end of the first voltage dividing resistor R302 and the third voltage dividing resistor R304. The output end of the voltage comparator PC302 is connected with the positive electrode of the signal power supply 3.3V through a pull-up resistor R305 and is connected with an alternating current power supply ZERO signal interface ZERO-R of the microprocessor through a third current limiting resistor R306. The ZERO signal interface ZERO-R of the alternating current power supply of the microprocessor is connected with the ground of the signal power supply of 3.3V through a fourth capacitor C306. The zero signal of the alternating current power supply assists in determining the on-off time of the thyristor Q001 and controlling the on-off of the thyristor Q001.
Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. In the description of the present invention, the meaning of "plurality" means at least two, for example, two, three or more, etc., unless specifically defined otherwise.
In the present invention, unless explicitly specified and limited otherwise, the terms "mounted," "connected," "secured," and the like are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; either directly or indirectly, through intermediaries, or both, may be in communication with each other or in interaction with each other, unless expressly defined otherwise. The specific meaning of the above terms in the present invention can be understood by those of ordinary skill in the art according to the specific circumstances.
While embodiments of the present invention have been shown and described above, it will be understood that the above embodiments are illustrative and not to be construed as limiting the invention, and that variations, modifications, alternatives and variations may be made to the above embodiments by one of ordinary skill in the art within the scope of the invention.
Claims (10)
1. An asynchronous motor speed controller, the asynchronous motor comprising motor windings connected to an ac power source, comprising:
a drive voltage control circuit including a thyristor; the thyristor comprises a first switch circuit which is connected in series between the alternating current power supply and the motor winding, and controls the on-off of the alternating current power supply and the motor winding to enable the motor winding to load driving voltage;
a voltage detection circuit connected to the live line and the neutral line of the ac power supply, respectively, for detecting an instantaneous voltage of the ac power supply;
the thyristor state detection circuit is respectively connected with two ends of the first switch circuit and used for detecting the on-off angle of the thyristor;
the microprocessor is respectively connected with the driving voltage control circuit, the voltage detection circuit and the thyristor state detection circuit, and is used for receiving the instantaneous voltage, the on-off angle and controlling the on-off of the thyristor; the microprocessor stores a voltage-rotating speed corresponding table of a plurality of driving voltage values corresponding to rotating speeds under specific loads, and searches the voltage-rotating speed corresponding table by a target rotating speed to obtain a target driving voltage; the microprocessor calculates the driving voltage of the current speed regulation period according to the instantaneous voltage and the on-off angle of the current speed regulation period, calculates the on-off angle of the next speed regulation period according to the driving voltage of the current speed regulation period and the target driving voltage, and controls the thyristor to be on-off to adjust the driving voltage of the next speed regulation period.
2. The asynchronous motor rotating speed controller according to claim 1, wherein the driving voltage of the current speed regulation period and the target driving voltage calculate a target output voltage of the next speed regulation period through a PID control algorithm, and the on-off angle of the next speed regulation period is calculated from the target output voltage.
3. An asynchronous motor speed controller according to claim 1, wherein the governor period is one-half the period of the ac power source.
4. An asynchronous motor speed controller according to claim 1, wherein the driving voltage values of the voltage-speed correspondence table include 1000 driving voltage values, and each driving voltage value is an arithmetic progression having 0 as a minimum value, 1%o of the voltage effective value of the standard ac power source as a maximum value, and the voltage effective value of the standard ac power source as a tolerance.
5. An asynchronous motor speed controller according to claim 1, wherein the voltage detection circuit comprises:
a first current limiting resistor is arranged on the first electrode,
a voltage transformer comprising a primary coil and a secondary coil; the primary coil comprises a first end and a second end; the secondary coil comprises a third end and a fourth end; the primary coil is connected with the first current limiting resistor in series and then is respectively connected with a live wire and a zero wire of the alternating current power supply;
the rectifying circuit comprises a first input end, a second input end and a first output end; the first input end and the second input end are respectively connected with the third end and the fourth end; the first output end is connected with the microprocessor.
6. The asynchronous motor speed controller according to any one of claims 1 to 5, wherein the thyristor state detection circuit comprises a second current limiting resistor, a rectifying and voltage stabilizing circuit, a controllable switching element and an output circuit; the controllable switch element comprises a fifth end, a sixth end and a second control end; the rectifying and voltage stabilizing circuit comprises a third input end, a fourth input end and a second output end; one end of the second current limiting resistor is connected with the third input end, and the other end of the second current limiting resistor and the fourth input end of the second current limiting resistor are respectively connected with two ends of the first switch circuit; the second output end is connected with the second control end; the fifth end and the sixth end are respectively connected with the output circuit and the ground; the output circuit is connected with the microprocessor; when the first switch circuit is communicated, the output circuit outputs a low level to the microprocessor; when the first switch circuit is turned off, the output circuit outputs a high level to the microprocessor.
7. An asynchronous motor speed control method applied to the asynchronous motor speed controller of any one of claims 1 to 6, the asynchronous motor comprising a motor winding connected to an ac power supply, characterized in that the asynchronous motor speed controller comprises a driving voltage control circuit, a voltage detection circuit, a thyristor state detection circuit, a microprocessor; the microprocessor is respectively connected with the driving voltage control circuit, the voltage detection circuit and the thyristor state detection circuit; the driving voltage control circuit comprises a thyristor, which comprises a first switch circuit; the first switch circuit is connected in series between the motor winding and the alternating current power supply; the voltage detection circuit is respectively connected with a live wire and a zero wire of the alternating current power supply; the thyristor state detection circuit is respectively connected with two ends of the first switch circuit; the method for controlling the rotating speed of the asynchronous motor comprises the following steps:
s1: measuring the rotating speeds of the asynchronous motor under a specific load and a plurality of driving voltage values to form a voltage-rotating speed correspondence table;
s2: storing the voltage-speed correspondence table into the microprocessor;
s3: the microprocessor inquires the voltage-rotating speed correspondence table according to the target rotating speed to obtain a target driving voltage corresponding to the target rotating speed;
s4: the microprocessor receives the instantaneous voltage output by the voltage detection circuit and the on-off angle of the thyristor detected by the thyristor state detection circuit;
s5: the microprocessor calculates the driving voltage of the current speed regulation period according to the instantaneous voltage of the current speed regulation period and the on-off angle of the current speed regulation period;
s6: the microprocessor calculates the target output voltage of the next speed regulation period according to the driving voltage of the current speed regulation period and the target driving voltage;
s7: the microprocessor calculates the on-off angle of the next speed regulation period according to the target output voltage;
s8: the microprocessor controls the on-off of the thyristor to provide the driving voltage of the next speed regulation period according to the on-off angle of the next speed regulation period;
and (3) repeating the steps S3-S8, and adjusting the rotating speed of the asynchronous motor in real time.
8. The method according to claim 7, wherein the microprocessor calculates the target output voltage of the next speed regulation period by using a PID control algorithm from the driving voltage of the current speed regulation period and the target driving voltage, and calculates the on-off angle of the next speed regulation period from the target output voltage of the next speed regulation period.
9. The method of claim 7, wherein the governor period is one half of a period of the ac power source.
10. The method according to any one of claims 7 to 9, wherein each driving voltage value in the voltage-rotation speed correspondence table is an arithmetic progression having 0 as a minimum value, a maximum value of the voltage effective value of the standard ac power supply, and 1%o of the voltage effective value of the standard ac power supply as a tolerance.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810724440.XA CN108616232B (en) | 2018-07-04 | 2018-07-04 | Asynchronous motor rotating speed controller and asynchronous motor rotating speed control method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810724440.XA CN108616232B (en) | 2018-07-04 | 2018-07-04 | Asynchronous motor rotating speed controller and asynchronous motor rotating speed control method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN108616232A CN108616232A (en) | 2018-10-02 |
| CN108616232B true CN108616232B (en) | 2024-01-09 |
Family
ID=63665998
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201810724440.XA Active CN108616232B (en) | 2018-07-04 | 2018-07-04 | Asynchronous motor rotating speed controller and asynchronous motor rotating speed control method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN108616232B (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109243285A (en) * | 2018-11-12 | 2019-01-18 | 湖北文理学院 | A kind of motor speed control experiment porch and method based on rapid control prototyping |
| CN113654203B (en) * | 2021-08-24 | 2022-10-04 | 广东电网有限责任公司 | Control method and device of three-phase alternating-current variable-frequency air conditioner |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4010411A (en) * | 1975-08-13 | 1977-03-01 | T. B. Wood's Sons Company | Power conversion apparatus |
| JP2004215826A (en) * | 2003-01-14 | 2004-08-05 | Matsushita Electric Ind Co Ltd | Revolution control device for laundry apparatus |
| CN201799769U (en) * | 2010-09-28 | 2011-04-20 | 广州三业科技有限公司 | Alternating current steel rail welding machine |
| CN105958878A (en) * | 2016-06-24 | 2016-09-21 | 南京工程学院 | Speed regulation apparatus and method for digitized thyristor direct current motor |
| CN107295125A (en) * | 2017-05-03 | 2017-10-24 | 青岛海信电子设备股份有限公司 | A kind of handheld terminal on-off circuit and control method |
| CN208433925U (en) * | 2018-07-04 | 2019-01-25 | 青岛海信电子设备股份有限公司 | A kind of speed Control of Induction Motor device |
-
2018
- 2018-07-04 CN CN201810724440.XA patent/CN108616232B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4010411A (en) * | 1975-08-13 | 1977-03-01 | T. B. Wood's Sons Company | Power conversion apparatus |
| JP2004215826A (en) * | 2003-01-14 | 2004-08-05 | Matsushita Electric Ind Co Ltd | Revolution control device for laundry apparatus |
| CN201799769U (en) * | 2010-09-28 | 2011-04-20 | 广州三业科技有限公司 | Alternating current steel rail welding machine |
| CN105958878A (en) * | 2016-06-24 | 2016-09-21 | 南京工程学院 | Speed regulation apparatus and method for digitized thyristor direct current motor |
| CN107295125A (en) * | 2017-05-03 | 2017-10-24 | 青岛海信电子设备股份有限公司 | A kind of handheld terminal on-off circuit and control method |
| CN208433925U (en) * | 2018-07-04 | 2019-01-25 | 青岛海信电子设备股份有限公司 | A kind of speed Control of Induction Motor device |
Non-Patent Citations (1)
| Title |
|---|
| 中板ACV700变频器应用及故障分析;李建武;酒钢科技(第03期);第216-219页 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN108616232A (en) | 2018-10-02 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CA1203566A (en) | Control and stabilizing system for damperless synchronous motor | |
| Lettenmaier et al. | Single-phase induction motor with an electronically controlled capacitor | |
| CN108431719B (en) | Solar motor controller for variable speed maximum power point tracking of inductive, permanent magnet AC motors | |
| US7768221B2 (en) | Method, system, and apparatus for controlling an electric motor | |
| JP5605336B2 (en) | Power supply | |
| CN108616232B (en) | Asynchronous motor rotating speed controller and asynchronous motor rotating speed control method | |
| US9531317B2 (en) | Power conversion apparatus, power conversion method, and motor system | |
| US20150260161A1 (en) | Control device for voltage source converter and operating method thereof | |
| EP2892149B1 (en) | Thyristor activation device | |
| CN103546087B (en) | A kind of non-frequency electric capacity governing of asynchronous machine and winding connect circuit | |
| US8217618B2 (en) | Energy-saving controller for three-phase induction motors | |
| CN102315819B (en) | Torque motor driving device for wire cut electrical discharge machines | |
| CN110299878B (en) | Control method of electro-magnetic doubly salient motor angle position semi-control power generation control system | |
| JP2008228477A (en) | Motor controller | |
| CN208433925U (en) | A kind of speed Control of Induction Motor device | |
| KR20020057819A (en) | Inverter control type generator | |
| EP0107351B1 (en) | Synchronous motor control | |
| CN114744655B (en) | Control method and topology device of flywheel energy storage system | |
| CN110492802B (en) | Conduction angle estimation method of controllable rectification power generation system of doubly salient electro-magnetic motor | |
| CN107231106A (en) | A kind of doubly fed induction generator system Direct Torque Controller for reducing torque ripple | |
| JP6128201B1 (en) | Power supply device, inverter device using the power supply device, converter device, refrigeration device using the inverter device or converter device, and air purifier | |
| de Azevedo et al. | Model reference adaptive control for squirrel-cage induction generator-based wind energy conversion systems | |
| KR101475025B1 (en) | A control system operating a rotary machine | |
| KR20190051334A (en) | Power converting apparatus | |
| WO2005031963A1 (en) | Method and device for controlling the operation of an ac motor |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| TA01 | Transfer of patent application right |
Effective date of registration: 20230830 Address after: 266510 No. 218, Qian Wan Gang Road, Huangdao District, Qingdao, Shandong. Applicant after: Qingdao Hisense network energy Co.,Ltd. Address before: 266100 No. 151, Zhuzhou Road, Laoshan District, Shandong, Qingdao Applicant before: QINGDAO HISENSE ELECTRONICS EQUIPMENT Co.,Ltd. |
|
| TA01 | Transfer of patent application right | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |