CN110932615B - Method and device for determining angle position of rotor of permanent magnet synchronous motor and motor - Google Patents
Method and device for determining angle position of rotor of permanent magnet synchronous motor and motor Download PDFInfo
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- CN110932615B CN110932615B CN201811005211.9A CN201811005211A CN110932615B CN 110932615 B CN110932615 B CN 110932615B CN 201811005211 A CN201811005211 A CN 201811005211A CN 110932615 B CN110932615 B CN 110932615B
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- 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
- H02P6/00—Arrangements for controlling synchronous motors or other dynamo-electric motors using electronic commutation dependent on the rotor position; Electronic commutators therefor
- H02P6/14—Electronic commutators
- H02P6/16—Circuit arrangements for detecting position
Abstract
The invention provides a method and a device for determining the angle position of a rotor of a permanent magnet synchronous motor and the permanent magnet synchronous motor. The permanent magnet synchronous motor is provided with a plurality of Hall position sensors and a Hall magnetic ring with the number of pole pairs being twice that of the permanent magnet synchronous motor, the Hall position sensors are used for outputting Hall position signals, and the method comprises the following steps: when the permanent magnet synchronous motor is powered on and is in a stop state, acquiring a Hall position signal level, and determining an initial Hall angle position and an initial sector value according to the Hall position signal level; adding current in the q-axis direction of the initial Hall angle position to enable the permanent magnet synchronous motor to rotate, and recording the change of a sector; determining the rotation direction of the permanent magnet synchronous motor and a Hall position zone bit according to the sector change value; and determining the rotor angle position of the permanent magnet synchronous motor according to the Hall position mark bit and the initial Hall angle position.
Description
Technical Field
The invention relates to the technical field of permanent magnet synchronous motors, in particular to a method and a device for determining the angle position of a rotor of a permanent magnet synchronous motor and the permanent magnet synchronous motor.
Background
The closed-loop control of the permanent magnet synchronous motor is realized under the condition that various control variables are measurable, such as feedback variables required by a rotating speed loop and a torque loop, including rotating speed, rotating angle and current. In order to adjust the speed and position of the rotor, a position sensor (such as a photoelectric encoder and a rotary transformer) with higher precision is generally required to be installed at the shaft end of the rotor of the motor for closed-loop control of the rotating speed and the position, the use of the position sensor ensures the control effect of the motor, but the defects of increased system cost and reduced system reliability exist. The low-resolution position sensor permanent magnet synchronous motor driving technology is a rotor position detection technology which can ensure the running performance of a motor, effectively control the system cost and improve the system reliability, but has the defects of low position information resolution, poor rotating speed measuring and calculating continuity, serious hysteresis and the like.
For example, in the related art, a scheme for acquiring a hall position signal level of a permanent magnet synchronous motor is as follows: the position of the rotor of the permanent magnet synchronous motor is detected through the Hall magnetic ring with the same pole pair number as the permanent magnet synchronous motor, the pole pair number of the Hall magnetic ring is the same as the pole pair number of the permanent magnet synchronous motor, and the Hall detection angle is ensured to completely correspond to the electrical angle of the motor. Three hall elements with phases different from each other by 120 degrees output hall position signals, as shown in fig. 1, the hall position signals 1, 2 and 3 respectively correspond to three phases A, B, C of the motor. For convenience of use, for certain requirements on installation of the hall magnetic ring, the upper limit of the hall signal 1 needs to be ensured to be zero-crossed along the reverse direction of the opposite potential of the corresponding motor a. The rotor position of the motor can be obtained by edge capture, wherein six sector values 2-3-1-5-4-6 correspond to 0 to 180 degrees (if the levels of the three hall position signals are 010, the sector value is 2, and if the levels of the three hall position signals are 011, the sector value is 3, and so on). It can be seen that the position resolution of the hall position acquisition scheme of the permanent magnet synchronous motor in the related art is 60 degrees of electrical angle, which cannot meet the application requirements for low-speed control occasions with higher requirements.
Disclosure of Invention
The present invention is directed to solving at least one of the problems of the prior art or the related art.
To this end, an aspect of the invention proposes a method of determining the angular position of a rotor of a permanent magnet synchronous motor.
Another aspect of the present invention is to provide an apparatus for determining an angular position of a rotor of a permanent magnet synchronous motor.
Yet another aspect of the present invention is to provide a permanent magnet synchronous motor.
In view of the above, according to one aspect of the present invention, there is provided a method of determining an angular position of a rotor of a permanent magnet synchronous motor, the permanent magnet synchronous motor being provided with a plurality of hall position sensors and with a hall magnet ring having a number of pole pairs twice that of the permanent magnet synchronous motor, the hall position sensors being configured to output hall position signals, the method comprising: when the permanent magnet synchronous motor is powered on and is in a stop state, acquiring a Hall position signal level, and determining an initial Hall angle position and an initial sector value according to the Hall position signal level; adding current in the q-axis direction of the initial Hall angle position to enable the permanent magnet synchronous motor to rotate, and recording a sector change value; determining the rotation direction of the permanent magnet synchronous motor and a Hall position zone bit according to the sector change value; and determining the rotor angle position of the permanent magnet synchronous motor according to the Hall position mark bit and the initial Hall angle position.
In the technical scheme, as the position of the rotor of the permanent magnet synchronous motor is detected by the Hall magnetic rings with the same pole pair number as the permanent magnet synchronous motor in the related technology, the problems that the Hall detection position precision is low and the application requirement cannot be met in a low-speed control occasion with high requirement can occur. The invention provides a method for determining the angular position of a permanent magnet synchronous motor rotor, which is characterized in that in order to improve the resolution of the level of a Hall position signal, Hall magnetic rings which are twice as many as the number of pole pairs of a motor are arranged, and three Hall position sensors with phases which are different from each other by 120 degrees output Hall position signals. And when the permanent magnet synchronous motor is powered on and is in a stop state, acquiring a Hall position signal level, and determining an initial Hall angle position and an initial sector value according to the Hall position signal level. And adding current in the q-axis direction of the initial Hall angle position to enable the permanent magnet synchronous motor to rotate, and recording the sector change value. Furthermore, the rotating direction of the permanent magnet synchronous motor and the Hall position mark bit are determined according to the sector change value, and the rotating direction of the permanent magnet synchronous motor can be determined according to the Hall position mark bit. And determining the rotor angle position of the permanent magnet synchronous motor according to the Hall position mark bit and the initial Hall angle position. By adopting the technical scheme of the invention, the position detection precision is improved by installing the Hall magnetic rings with twice of the number of pole pairs of the motor, the problem of determining the initial position of the motor caused by adopting the Hall magnetic rings with twice of the number of pole pairs is solved, and the low-speed control performance of the permanent magnet synchronous motor is improved under the condition of not increasing the cost.
The method for determining the angular position of the rotor of the permanent magnet synchronous motor according to the invention can also have the following technical characteristics:
in the above technical solution, preferably, determining an initial hall angle position and an initial sector value according to a hall position signal level specifically includes: acquiring a sector value within every 30 degrees as an initial sector value according to the Hall position signal level; and respectively acquiring the Hall angle corresponding to each sector as an initial Hall angle position.
In the technical scheme, after the permanent magnet synchronous motor is electrified and in a stop state, the three-phase Hall position signal level is read, the sector value within each 30 degrees range is obtained according to the three-phase Hall position signal level to serve as the initial sector value, and the Hall angle corresponding to each sector is obtained to serve as the initial Hall angle position. For example, between 0 ° and 180 °, 6 sectors are divided by dividing every 30 ° range, and the sector value is determined according to the three-phase hall position signal level corresponding to each sector, such as determining the initial sector value as 6-4-5-1-3-2, i.e., the first sector value is 6, the second sector value is 4, the third sector value is 5, the fourth sector value is 1, the fifth sector value is 3, and the sixth sector value is 2. Taking the corresponding angle of plus or minus 15 degrees of each sector as the initial hall angle position, that is, the angles taken in the six sectors are 15 °, 45 °, 75 °, 105 °, 135 °, 165 °, respectively, and then recording the initial hall angle position as 15 °, 45 °, 75 °, 105 °, 135 °, 165 °. The position resolution of 60 degrees in the related technical scheme is improved to 30 degrees, and the low-speed running performance can be further improved.
In any of the above technical solutions, preferably, the determining the rotation direction and the hall position flag bit of the permanent magnet synchronous motor according to the sector variation value specifically includes: setting an initial value of a Hall position flag bit to be 0; when preset change information exists, the Hall position zone bit is inverted, and the preset change information comprises a change from a first sector value in a range of 180 degrees to a last sector value in the range of 180 degrees or a change from the last sector value to the first sector value; when the preset change information does not exist, if the sector change value is a first sequence change value, the rotation direction is determined to be positive rotation, and the Hall position zone bit is kept unchanged; and if the sector change value is the second sequence change value, determining that the rotation direction is reverse, and inverting the Hall position zone bit.
In the technical scheme, the initial value of the Hall position flag bit is set to be 0, the Hall position flag bit is inverted when the value of the first sector is changed to the value of the last sector (the sixth sector value) or the value of the last sector is changed to the value of the first sector, for example, the initial sector value is 6-4-5-1-3-2, and the Hall position flag bit is inverted when the value of the sector is changed from 6 to 2 or from 2 to 6. When the change condition does not occur, if the sector change value is a first sequence change value (namely, positive sequence change), if the sector change value is changed according to 6-4-5-1-3-2-6, the rotation direction is determined to be positive rotation, and the Hall position mark bit is kept unchanged; and if the sector change value is a second sequence change value (namely reverse sequence change), if the sector change value is changed according to 6-2-3-1-5-4-6, determining that the rotating direction is reverse and the Hall position mark bit is reversed, namely, accurately representing the rotating condition of the permanent magnet synchronous motor by setting the Hall position mark bit.
In any of the above technical solutions, preferably, determining the rotor angle position of the permanent magnet synchronous motor according to the hall position flag bit and the initial hall angle position specifically includes: when the Hall position zone bit is '0', the rotor angle position is equal to the initial Hall angle position; when the Hall position flag is "1", the rotor angular position is equal to the initial Hall angular position plus 180 °.
In the technical scheme, when the Hall position flag bit is '0', the rotating direction of the permanent magnet synchronous motor is positive rotation, and the current position of the permanent magnet synchronous motor is in the interval of 0-180 degrees, the rotor angle position is equal to the initial Hall angle position; when the Hall position zone bit is '1', the rotating direction of the permanent magnet synchronous motor is reverse, the current position of the permanent magnet synchronous motor is in the range of 180-360 degrees, the rotor angle position is equal to the initial Hall angle position plus 180 degrees, and the problem of determining the initial position of the motor caused by the adoption of the double logarithm Hall magnetic ring is solved.
According to another aspect of the present invention, there is provided an apparatus for determining an angular position of a rotor of a permanent magnet synchronous motor, the permanent magnet synchronous motor being provided with a plurality of hall position sensors and with a hall magnet ring having a number of pole pairs twice that of the permanent magnet synchronous motor, the hall position sensors being configured to output hall position signals, the apparatus comprising: a memory for storing a computer program; a processor for executing a computer program to: when the permanent magnet synchronous motor is powered on and is in a stop state, acquiring a Hall position signal level, and determining an initial Hall angle position and an initial sector value according to the Hall position signal level; adding current in the q-axis direction of the initial Hall angle position to enable the permanent magnet synchronous motor to rotate, and recording a sector change value; determining the rotation direction of the permanent magnet synchronous motor and a Hall position zone bit according to the sector change value; and determining the rotor angle position of the permanent magnet synchronous motor according to the Hall position mark bit and the initial Hall angle position.
In the technical scheme, as the position of the rotor of the permanent magnet synchronous motor is detected by the Hall magnetic rings with the same pole pair number as the permanent magnet synchronous motor in the related technology, the problems that the Hall detection position precision is low and the application requirement cannot be met in a low-speed control occasion with high requirement can occur. The invention provides a method for determining the angular position of a permanent magnet synchronous motor rotor, which is characterized in that in order to improve the resolution of the level of a Hall position signal, Hall magnetic rings which are twice as many as the number of pole pairs of a motor are arranged, and three Hall position sensors with phases which are different from each other by 120 degrees output Hall position signals. And when the permanent magnet synchronous motor is powered on and is in a stop state, acquiring a Hall position signal level, and determining an initial Hall angle position and an initial sector value according to the Hall position signal level. And adding current in the q-axis direction of the initial Hall angle position to enable the permanent magnet synchronous motor to rotate, and recording the sector change value. Furthermore, the rotating direction of the permanent magnet synchronous motor and the Hall position mark bit are determined according to the sector change value, and the rotating direction of the permanent magnet synchronous motor can be determined according to the Hall position mark bit. And determining the rotor angle position of the permanent magnet synchronous motor according to the Hall position mark bit and the initial Hall angle position. By adopting the technical scheme of the invention, the position detection precision is improved by installing the Hall magnetic rings with twice of the number of pole pairs of the motor, the problem of determining the initial position of the motor caused by adopting the Hall magnetic rings with twice of the number of pole pairs is solved, and the low-speed control performance of the permanent magnet synchronous motor is improved under the condition of not increasing the cost.
The device for determining the angular position of the rotor of the permanent magnet synchronous motor according to the invention can also have the following technical characteristics:
in the foregoing technical solution, preferably, the processor is specifically configured to execute a computer program to: acquiring a sector value within every 30 degrees as an initial sector value according to the Hall position signal level; and respectively acquiring the Hall angle corresponding to each sector as an initial Hall angle position.
In the technical scheme, after the permanent magnet synchronous motor is electrified and in a stop state, the three-phase Hall position signal level is read, the sector value within each 30 degrees range is obtained according to the three-phase Hall position signal level to serve as the initial sector value, and the Hall angle corresponding to each sector is obtained to serve as the initial Hall angle position. For example, between 0 ° and 180 °, 6 sectors are divided by dividing every 30 ° range, and the sector value is determined according to the three-phase hall position signal level corresponding to each sector, such as determining the initial sector value as 6-4-5-1-3-2, i.e., the first sector value is 6, the second sector value is 4, the third sector value is 5, the fourth sector value is 1, the fifth sector value is 3, and the sixth sector value is 2. Taking the corresponding angle of plus or minus 15 degrees of each sector as the initial hall angle position, that is, the angles taken in the six sectors are 15 °, 45 °, 75 °, 105 °, 135 °, 165 °, respectively, and then recording the initial hall angle position as 15 °, 45 °, 75 °, 105 °, 135 °, 165 °. The position resolution of 60 degrees in the related technical scheme is improved to 30 degrees, and the low-speed running performance can be further improved.
In any of the above technical solutions, preferably, the processor is specifically configured to execute a computer program to: setting an initial value of a Hall position flag bit to be 0; when preset change information exists, the Hall position zone bit is inverted, and the preset change information comprises a change from a first sector value in a range of 180 degrees to a last sector value in the range of 180 degrees or a change from the last sector value to the first sector value; when the preset change information does not exist, if the sector change value is a first sequence change value, the rotation direction is determined to be positive rotation, and the Hall position zone bit is kept unchanged; and if the sector change value is the second sequence change value, determining that the rotation direction is reverse, and inverting the Hall position zone bit.
In the technical scheme, the initial value of the Hall position flag bit is set to be 0, the Hall position flag bit is inverted when the value of the first sector is changed to the value of the last sector (the sixth sector value) or the value of the last sector is changed to the value of the first sector, for example, the initial sector value is 6-4-5-1-3-2, and the Hall position flag bit is inverted when the value of the sector is changed from 6 to 2 or from 2 to 6. When the change condition does not occur, if the sector change value is a first sequence change value (namely, positive sequence change), if the sector change value is changed according to 6-4-5-1-3-2-6, the rotation direction is determined to be positive rotation, and the Hall position mark bit is kept unchanged; and if the sector change value is a second sequence change value (namely reverse sequence change), if the sector change value is changed according to 6-2-3-1-5-4-6, determining that the rotating direction is reverse and the Hall position mark bit is reversed, namely, accurately representing the rotating condition of the permanent magnet synchronous motor by setting the Hall position mark bit.
In any of the above technical solutions, preferably, the processor is specifically configured to execute a computer program to: when the Hall position zone bit is '0', the rotor angle position is equal to the initial Hall angle position; when the Hall position flag is "1", the rotor angular position is equal to the initial Hall angular position plus 180 °.
In the technical scheme, when the Hall position flag bit is '0', the rotating direction of the permanent magnet synchronous motor is positive rotation, and the current position of the permanent magnet synchronous motor is in the interval of 0-180 degrees, the rotor angle position is equal to the initial Hall angle position; when the Hall position zone bit is '1', the rotating direction of the permanent magnet synchronous motor is reverse, the current position of the permanent magnet synchronous motor is in the range of 180-360 degrees, the rotor angle position is equal to the initial Hall angle position plus 180 degrees, and the problem of determining the initial position of the motor caused by the adoption of the double logarithm Hall magnetic ring is solved.
According to another aspect of the present invention, a permanent magnet synchronous motor is provided, which includes any one of the above-mentioned technical solutions for determining the angular position of the rotor of the permanent magnet synchronous motor.
The permanent magnet synchronous motor provided by the invention comprises the device for determining the angle position of the rotor of the permanent magnet synchronous motor in any technical scheme, and can realize all the beneficial effects of the device for determining the angle position of the rotor of the permanent magnet synchronous motor in any technical scheme.
In the above technical solution, preferably, the method further includes: a plurality of Hall position sensors for outputting Hall position signals; the number of pole pairs of the plurality of Hall magnetic rings is twice that of the pole pairs of the permanent magnet synchronous motor.
In the technical scheme, in order to improve the resolution of the level of the Hall position signal, two times of Hall magnetic rings of the number of pole pairs of the motor are installed, and three Hall position sensors with phases different from each other by 120 degrees output the Hall position signal. The position resolution of 60 degrees in the related technical scheme is improved to 30 degrees, and the low-speed running performance can be further improved.
Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention.
Drawings
The above and/or additional aspects and advantages of the present invention will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:
FIG. 1 is a schematic diagram illustrating a counter electromotive force of a permanent magnet synchronous motor and a Hall signal in a related art;
FIG. 2 illustrates a flow diagram of a method of determining an angular position of a rotor of a permanent magnet synchronous motor according to an embodiment of the present invention;
fig. 3 is a schematic diagram showing the correspondence between the back electromotive force of the permanent magnet synchronous motor and the hall signal according to an embodiment of the present invention;
FIG. 4 illustrates a q-axis current injection schematic of an embodiment of the present invention;
fig. 5 shows a schematic view of an arrangement for determining the angular position of a rotor of a permanent magnet synchronous motor according to an embodiment of the invention.
Detailed Description
In order that the above objects, features and advantages of the present invention can be more clearly understood, a more particular description of the invention will be rendered by reference to the appended drawings. It should be noted that the embodiments of the present invention and features of the embodiments may be combined with each other without conflict.
In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention, however, the present invention may be practiced in other ways than those specifically described herein, and therefore the scope of the present invention is not limited to the specific embodiments disclosed below.
In an embodiment of the first aspect of the present invention, a method for determining an angular position of a rotor of a permanent magnet synchronous motor is provided, where the permanent magnet synchronous motor is provided with a plurality of hall position sensors and a hall magnetic ring having a number of pole pairs twice that of the permanent magnet synchronous motor, and the hall position sensors are configured to output hall position signals, and fig. 2 illustrates a flowchart of the method for determining the angular position of the rotor of the permanent magnet synchronous motor according to an embodiment of the present invention. Wherein, the method comprises the following steps:
and 208, determining the rotor angle position of the permanent magnet synchronous motor according to the Hall position zone bit and the initial Hall angle position.
In the embodiment, as the position of the rotor of the permanent magnet synchronous motor is detected by the hall magnetic rings with the same pole pair number as the permanent magnet synchronous motor in the related art, the problems that the hall detection position precision is low and the application requirement cannot be met in a low-speed control occasion with high requirement can occur. The invention provides a method for determining the angular position of a permanent magnet synchronous motor rotor, which is characterized in that in order to improve the resolution of the level of a Hall position signal, Hall magnetic rings which are twice as many as the number of pole pairs of a motor are arranged, and three Hall position sensors with phases which are different from each other by 120 degrees output Hall position signals. And when the permanent magnet synchronous motor is powered on and is in a stop state, acquiring a Hall position signal level, and determining an initial Hall angle position and an initial sector value according to the Hall position signal level. And adding current in the q-axis direction of the initial Hall angle position to enable the permanent magnet synchronous motor to rotate, and recording the sector change value. Furthermore, the rotating direction of the permanent magnet synchronous motor and the Hall position mark bit are determined according to the sector change value, and the rotating direction of the permanent magnet synchronous motor can be determined according to the Hall position mark bit. And determining the rotor angle position of the permanent magnet synchronous motor according to the Hall position mark bit and the initial Hall angle position. By adopting the technical scheme of the invention, the position detection precision is improved by installing the Hall magnetic rings with twice of the number of pole pairs of the motor, the problem of determining the initial position of the motor caused by adopting the Hall magnetic rings with twice of the number of pole pairs is solved, and the low-speed control performance of the permanent magnet synchronous motor is improved under the condition of not increasing the cost.
Preferably, in step 202, determining an initial hall angle position and an initial sector value according to the hall position signal level specifically includes: acquiring a sector value within every 30 degrees as an initial sector value according to the Hall position signal level; and respectively acquiring the Hall angle corresponding to each sector as an initial Hall angle position.
In this embodiment, after the permanent magnet synchronous motor is powered on and in a stopped state, the three-phase hall position signal level is read, a sector value within each 30 ° range is obtained according to the three-phase hall position signal level to serve as an initial sector value, and then a hall angle corresponding to each sector is obtained to serve as an initial hall angle position. For example, between 0 ° and 180 °, 6 sectors are divided by dividing every 30 ° range, and the sector value is determined according to the three-phase hall position signal level corresponding to each sector, such as determining the initial sector value as 6-4-5-1-3-2, i.e., the first sector value is 6, the second sector value is 4, the third sector value is 5, the fourth sector value is 1, the fifth sector value is 3, and the sixth sector value is 2. Taking the corresponding angle of plus or minus 15 degrees of each sector as the initial hall angle position, that is, the angles taken in the six sectors are 15 °, 45 °, 75 °, 105 °, 135 °, 165 °, respectively, and then recording the initial hall angle position as 15 °, 45 °, 75 °, 105 °, 135 °, 165 °. The position resolution of 60 degrees in the related technical scheme is improved to 30 degrees, and the low-speed running performance can be further improved.
It should be noted that, there are various methods for obtaining the hall angle corresponding to each sector, and the positive and negative angles may be set according to the situation, for example, the corresponding angles of positive 10 ° and negative 20 ° of each sector are taken as the initial hall angle positions, that is, the angles taken in the six sectors are respectively 10 °, 40 °, 70 °, 100 °, 130 °, and 160 °. And fitting a curve to the angle in each sector to obtain the most appropriate Hall angle.
Preferably, in step 206, determining the rotation direction and the hall position flag of the permanent magnet synchronous motor according to the sector variation value specifically includes: setting an initial value of a Hall position flag bit to be 0; when preset change information exists, the Hall position zone bit is inverted, and the preset change information comprises a change from a first sector value in a range of 180 degrees to a last sector value in the range of 180 degrees or a change from the last sector value to the first sector value; when the preset change information does not exist, if the sector change value is a first sequence change value, the rotation direction is determined to be positive rotation, and the Hall position zone bit is kept unchanged; and if the sector change value is the second sequence change value, determining that the rotation direction is reverse, and inverting the Hall position zone bit.
In this embodiment, the initial value of the hall position flag is set to "0", and the hall position flag is inverted when changing from the first sector value to the last sector value (sixth sector value) or from the last sector value to the first sector value, for example, the initial sector value is 6-4-5-1-3-2, and then the hall position flag is inverted when the sector value changes from 6 to 2 or from 2 to 6 occurs. When the change condition does not occur, if the sector change value is a first sequence change value (namely, positive sequence change), if the sector change value is changed according to 6-4-5-1-3-2-6, the rotation direction is determined to be positive rotation, and the Hall position mark bit is kept unchanged; and if the sector change value is a second sequence change value (namely reverse sequence change), if the sector change value is changed according to 6-2-3-1-5-4-6, determining that the rotating direction is reverse and the Hall position mark bit is reversed, namely, accurately representing the rotating condition of the permanent magnet synchronous motor by setting the Hall position mark bit.
Preferably, in step 208, determining the rotor angle position of the permanent magnet synchronous motor according to the hall position flag bit and the initial hall angle position specifically includes: when the Hall position zone bit is '0', the rotor angle position is equal to the initial Hall angle position; when the Hall position flag is "1", the rotor angular position is equal to the initial Hall angular position plus 180 °.
In this embodiment, when the hall position flag is "0", it indicates that the rotation direction of the permanent magnet synchronous motor is positive rotation, and the current position of the permanent magnet synchronous motor is within the interval of 0 ° to 180 °, the rotor angle position is equal to the initial hall angle position; when the Hall position zone bit is '1', the rotating direction of the permanent magnet synchronous motor is reverse, the current position of the permanent magnet synchronous motor is in the range of 180-360 degrees, the rotor angle position is equal to the initial Hall angle position plus 180 degrees, and the problem of determining the initial position of the motor caused by the adoption of the double logarithm Hall magnetic ring is solved.
In the embodiment of the invention, in order to improve the resolution of the hall position, two times of the number of the pole pairs of the hall magnetic rings are installed, three hall elements with the phase difference of 120 degrees output hall signals, as shown in fig. 3, and the hall signals 1, 2 and 3 respectively correspond to three phases A, B, C of the motor. For convenience of use, for certain requirements on installation of the hall magnetic ring, the upper limit of the hall signal 1 needs to be ensured to be zero-crossed along the reverse direction of the opposite potential of the corresponding motor a. Six Hall signal states are obtained according to the three-phase Hall, corresponding to six sector values, 6-4-5-1-3-2 corresponds to 0-180 degrees. Therefore, two motor positions are generated at each hall position, and the current motor position is required to be known in an interval of 0-180 degrees or an interval of 180-360 degrees, and in order to solve the problem, the initial position of the motor is required to be determined before starting.
The motor initial position acquisition method comprises the following steps: after the motor and the controller thereof are powered on, the motor is in a stop state, and the level of the three-phase Hall signal is read; and acquiring sector values within the range of 30 degrees according to the levels of the three-phase Hall signals. The sector value 6-4-5-1-3-2 can be selected to correspond to the angle of 15 degrees, 45 degrees, 75 degrees, 105 degrees, 135 degrees and 165 degrees, and the initial position of the Hall is recorded as 15 degrees, 45 degrees, 75 degrees, 105 degrees, 135 degrees and 165 degrees. Injecting current into the obtained hall initial position q axis, wherein the q axis current enables the motor to rotate and records the change of the hall sector in the rotating process as shown in fig. 4. Setting the initial value of the Hall position zone bit to be 0, when the Hall signal state is changed from 6 to 2 or from 2 to 6, if the Hall sector is changed to 6-2-3-1-5-4-6, the motor rotates reversely, and the Hall position zone bit is inverted; if the Hall sector changes according to 6-4-5-1-3-2-6, the motor rotates forwards, and the Hall position zone bit remains unchanged. When the Hall position mark is 0, the position of the motor rotor is equal to the Hall initial position, and when the Hall position mark is 1, the position of the motor rotor is equal to the Hall initial position plus 180 degrees. The embodiment improves the position resolution of 60 degrees to 30 degrees, and improves the position precision to improve the low-speed running performance.
In the embodiment of the second aspect of the present invention, an apparatus for determining an angular position of a rotor of a permanent magnet synchronous motor is provided, the permanent magnet synchronous motor is provided with a plurality of hall position sensors, and a hall magnetic ring having a number of pole pairs twice that of the permanent magnet synchronous motor is provided, the hall position sensors are used for outputting hall position signals, and fig. 5 shows a schematic diagram of an apparatus 50 for determining an angular position of a rotor of a permanent magnet synchronous motor according to an embodiment of the present invention. Wherein the device 50 comprises:
a memory 502 for storing a computer program;
a processor 504 for executing a computer program to: when the permanent magnet synchronous motor is powered on and is in a stop state, acquiring a Hall position signal level, and determining an initial Hall angle position and an initial sector value according to the Hall position signal level; adding current in the q-axis direction of the initial Hall angle position to enable the permanent magnet synchronous motor to rotate, and recording a sector change value; determining the rotation direction of the permanent magnet synchronous motor and a Hall position zone bit according to the sector change value; and determining the rotor angle position of the permanent magnet synchronous motor according to the Hall position mark bit and the initial Hall angle position.
In the embodiment, as the position of the rotor of the permanent magnet synchronous motor is detected by the hall magnetic rings with the same pole pair number as the permanent magnet synchronous motor in the related art, the problems that the hall detection position precision is low and the application requirement cannot be met in a low-speed control occasion with high requirement can occur. The invention provides a method for determining the angular position of a permanent magnet synchronous motor rotor, which is characterized in that in order to improve the resolution of the level of a Hall position signal, Hall magnetic rings which are twice as many as the number of pole pairs of a motor are arranged, and three Hall position sensors with phases which are different from each other by 120 degrees output Hall position signals. And when the permanent magnet synchronous motor is powered on and is in a stop state, acquiring a Hall position signal level, and determining an initial Hall angle position and an initial sector value according to the Hall position signal level. And adding current in the q-axis direction of the initial Hall angle position to enable the permanent magnet synchronous motor to rotate, and recording the sector change value. Furthermore, the rotating direction of the permanent magnet synchronous motor and the Hall position mark bit are determined according to the sector change value, and the rotating direction of the permanent magnet synchronous motor can be determined according to the Hall position mark bit. And determining the rotor angle position of the permanent magnet synchronous motor according to the Hall position mark bit and the initial Hall angle position. By adopting the technical scheme of the invention, the position detection precision is improved by installing the Hall magnetic rings with twice of the number of pole pairs of the motor, the problem of determining the initial position of the motor caused by adopting the Hall magnetic rings with twice of the number of pole pairs is solved, and the low-speed control performance of the permanent magnet synchronous motor is improved under the condition of not increasing the cost.
Preferably, the processor 504 is specifically configured to execute a computer program to: acquiring a sector value within every 30 degrees as an initial sector value according to the Hall position signal level; and respectively acquiring the Hall angle corresponding to each sector as an initial Hall angle position.
In this embodiment, after the permanent magnet synchronous motor is powered on and in a stopped state, the three-phase hall position signal level is read, a sector value within each 30 ° range is obtained according to the three-phase hall position signal level to serve as an initial sector value, and then a hall angle corresponding to each sector is obtained to serve as an initial hall angle position. For example, between 0 ° and 180 °, 6 sectors are divided by dividing every 30 ° range, and the sector value is determined according to the three-phase hall position signal level corresponding to each sector, such as determining the initial sector value as 6-4-5-1-3-2, i.e., the first sector value is 6, the second sector value is 4, the third sector value is 5, the fourth sector value is 1, the fifth sector value is 3, and the sixth sector value is 2. Taking the corresponding angle of plus or minus 15 degrees of each sector as the initial hall angle position, that is, the angles taken in the six sectors are 15 °, 45 °, 75 °, 105 °, 135 °, 165 °, respectively, and then recording the initial hall angle position as 15 °, 45 °, 75 °, 105 °, 135 °, 165 °. The position resolution of 60 degrees in the related technical scheme is improved to 30 degrees, and the low-speed running performance can be further improved.
It should be noted that, there are various methods for obtaining the hall angle corresponding to each sector, and the positive and negative angles may be set according to the situation, for example, the corresponding angles of positive 10 ° and negative 20 ° of each sector are taken as the initial hall angle positions, that is, the angles taken in the six sectors are respectively 10 °, 40 °, 70 °, 100 °, 130 °, and 160 °. And fitting a curve to the angle in each sector to obtain the most appropriate Hall angle.
Preferably, the processor 504 is specifically configured to execute a computer program to: setting an initial value of a Hall position flag bit to be 0; when preset change information exists, the Hall position zone bit is inverted, and the preset change information comprises a change from a first sector value in a range of 180 degrees to a last sector value in the range of 180 degrees or a change from the last sector value to the first sector value; when the preset change information does not exist, if the sector change value is a first sequence change value, the rotation direction is determined to be positive rotation, and the Hall position zone bit is kept unchanged; and if the sector change value is the second sequence change value, determining that the rotation direction is reverse, and inverting the Hall position zone bit.
In this embodiment, the initial value of the hall position flag is set to "0", and the hall position flag is inverted when changing from the first sector value to the last sector value (sixth sector value) or from the last sector value to the first sector value, for example, the initial sector value is 6-4-5-1-3-2, and then the hall position flag is inverted when the sector value changes from 6 to 2 or from 2 to 6 occurs. When the change condition does not occur, if the sector change value is a first sequence change value (namely, positive sequence change), if the sector change value is changed according to 6-4-5-1-3-2-6, the rotation direction is determined to be positive rotation, and the Hall position mark bit is kept unchanged; and if the sector change value is a second sequence change value (namely reverse sequence change), if the sector change value is changed according to 6-2-3-1-5-4-6, determining that the rotating direction is reverse and the Hall position mark bit is reversed, namely, accurately representing the rotating condition of the permanent magnet synchronous motor by setting the Hall position mark bit.
Preferably, the processor 504 is specifically configured to execute a computer program to: when the Hall position zone bit is '0', the rotor angle position is equal to the initial Hall angle position; when the Hall position flag is "1", the rotor angular position is equal to the initial Hall angular position plus 180 °.
In this embodiment, when the hall position flag is "0", it indicates that the rotation direction of the permanent magnet synchronous motor is positive rotation, and the current position of the permanent magnet synchronous motor is within the interval of 0 ° to 180 °, the rotor angle position is equal to the initial hall angle position; when the Hall position zone bit is '1', the rotating direction of the permanent magnet synchronous motor is reverse, the current position of the permanent magnet synchronous motor is in the range of 180-360 degrees, the rotor angle position is equal to the initial Hall angle position plus 180 degrees, and the problem of determining the initial position of the motor caused by the adoption of the double logarithm Hall magnetic ring is solved.
In an embodiment of the third aspect of the present invention, a permanent magnet synchronous motor is provided, which includes the apparatus for determining the angular position of the rotor of the permanent magnet synchronous motor according to any of the above embodiments.
The permanent magnet synchronous motor provided by the invention comprises the device for determining the angle position of the rotor of the permanent magnet synchronous motor in any embodiment, and all beneficial effects of the device for determining the angle position of the rotor of the permanent magnet synchronous motor in any embodiment can be realized.
Preferably, the method further comprises the following steps: a plurality of Hall position sensors for outputting Hall position signals; the number of pole pairs of the plurality of Hall magnetic rings is twice that of the pole pairs of the permanent magnet synchronous motor.
In the embodiment, in order to improve the resolution of the Hall position signal level, a Hall magnetic ring with twice the number of pole pairs of the motor is installed, and three Hall position sensors with phases different from each other by 120 degrees output Hall position signals. The position resolution of 60 degrees in the related technical scheme is improved to 30 degrees, and the low-speed running performance can be further improved.
In the description herein, the terms "first" and "second" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance unless explicitly stated or limited otherwise; the terms "connected," "mounted," "secured," and the like are to be construed broadly and include, for example, fixed connections, removable connections, or integral connections; may be directly connected or indirectly connected through an intermediate. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.
In the description herein, the description of the terms "one embodiment," "some embodiments," "specific embodiments," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.
The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (8)
1. A method for determining the angular position of a rotor of a permanent magnet synchronous motor is characterized in that the permanent magnet synchronous motor is provided with a plurality of Hall position sensors and a Hall magnetic ring with the number of pole pairs being twice that of the permanent magnet synchronous motor, the Hall position sensors are used for outputting Hall position signals, and the method comprises the following steps:
when the permanent magnet synchronous motor is powered on and is in a stop state, acquiring a Hall position signal level, and determining an initial Hall angle position and an initial sector value according to the Hall position signal level;
adding current in the q-axis direction of the initial Hall angle position to enable the permanent magnet synchronous motor to rotate, and recording a sector change value;
determining the rotation direction of the permanent magnet synchronous motor and a Hall position zone bit according to the sector change value;
determining the rotor angle position of the permanent magnet synchronous motor according to the Hall position mark bit and the initial Hall angle position;
the determining of the initial hall angle position and the initial sector value according to the hall position signal level specifically includes:
dividing sectors within every 30 degrees, and acquiring a sector value within every 30 degrees as the initial sector value according to the Hall position signal level corresponding to each sector;
and respectively acquiring the Hall angle corresponding to each sector as the initial Hall angle position.
2. The method for determining the angular position of the rotor of the permanent magnet synchronous motor according to claim 1, wherein the determining the rotation direction and the hall position flag bit of the permanent magnet synchronous motor according to the sector variation value specifically comprises:
setting the initial value of the Hall position flag bit to be 0;
when preset change information exists, inverting the Hall position zone bit, wherein the preset change information comprises changing from a first sector value in a range of 180 degrees to a last sector value in the range of 180 degrees or changing from the last sector value to the first sector value;
when the preset change information does not exist, if the sector change value is a first sequence change value, determining that the rotating direction is positive rotation, and keeping the Hall position zone bit unchanged; and if the sector change value is a second sequence change value, determining that the rotating direction is reverse, and inverting the Hall position zone bit.
3. The method for determining the angular position of the rotor of the permanent magnet synchronous motor according to claim 1 or 2, wherein the determining the angular position of the rotor of the permanent magnet synchronous motor according to the hall position flag bit and the initial hall angular position specifically comprises:
when the Hall position flag bit is '0', the rotor angle position is equal to the initial Hall angle position;
when the hall position flag bit is "1", the rotor angular position is equal to the initial hall angular position plus 180 °.
4. The utility model provides a confirm device of PMSM rotor angular position which characterized in that, PMSM is provided with a plurality of hall position sensor to and be provided with the hall magnetic ring that the number of pole pairs is twice of PMSM's number of pole pairs, hall position sensor is used for exporting hall position signal, the device includes:
a memory for storing a computer program;
a processor for executing the computer program to:
when the permanent magnet synchronous motor is powered on and is in a stop state, acquiring a Hall position signal level, and determining an initial Hall angle position and an initial sector value according to the Hall position signal level;
adding current in the q-axis direction of the initial Hall angle position to enable the permanent magnet synchronous motor to rotate, and recording a sector change value;
determining the rotation direction of the permanent magnet synchronous motor and a Hall position zone bit according to the sector change value;
determining the rotor angle position of the permanent magnet synchronous motor according to the Hall position mark bit and the initial Hall angle position;
the processor is specifically configured to execute the computer program to:
dividing sectors within every 30 degrees, and acquiring a sector value within every 30 degrees as the initial sector value according to the Hall position signal level corresponding to each sector;
and respectively acquiring the Hall angle corresponding to each sector as the initial Hall angle position.
5. Device for determining the angular position of a rotor of a permanent magnet synchronous motor according to claim 4, characterized in that the processor is specifically adapted to execute the computer program to:
setting the initial value of the Hall position flag bit to be 0;
when preset change information exists, inverting the Hall position zone bit, wherein the preset change information comprises changing from a first sector value in a range of 180 degrees to a last sector value in the range of 180 degrees or changing from the last sector value to the first sector value;
when the preset change information does not exist, if the sector change value is a first sequence change value, determining that the rotating direction is positive rotation, and keeping the Hall position zone bit unchanged; and if the sector change value is a second sequence change value, determining that the rotating direction is reverse, and inverting the Hall position zone bit.
6. Device for determining the angular position of a rotor of a permanent magnet synchronous motor according to claim 4 or 5, characterized in that the processor is specifically adapted to execute the computer program to:
when the Hall position flag bit is '0', the rotor angle position is equal to the initial Hall angle position;
when the hall position flag bit is "1", the rotor angular position is equal to the initial hall angular position plus 180 °.
7. A permanent magnet synchronous motor, comprising:
the apparatus for determining the angular position of a rotor of a permanent magnet synchronous motor according to any of claims 4 to 6.
8. The permanent magnet synchronous motor according to claim 7, further comprising:
a plurality of Hall position sensors for outputting Hall position signals;
the number of pole pairs of the plurality of Hall magnetic rings is twice that of the pole pairs of the permanent magnet synchronous motor.
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| CN113358010B (en) * | 2021-05-31 | 2023-03-07 | 新乡航空工业(集团)有限公司上海分公司 | Hall sector boundary detection method and system for three-phase permanent magnet synchronous motor |
| CN114448299B (en) * | 2022-01-21 | 2024-02-06 | 湖南进芯电子科技有限公司 | Hall synchronous angle determining method and system |
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