阅读说明：本技术 一种基于霍尔传感器电机的复合式控制方法与系统 (Combined control method and system based on Hall sensor motor ) 是由 董浩天 毛剑峰 朱耀坤 李雨楠 斯梓展 缪骏豪 彭小伟 刘泽琨 褚熠 王俊 于 2021-03-19 设计创作，主要内容包括：本发明公开了一种基于霍尔传感器电机的复合式控制方法与系统,涉及电机控制领域,具体包括步骤：获取各霍尔传感器的连续实时输出信号；判断当前采集时刻的输出信号与上一采集时刻的输出信号是否一致,若是,控制电机保持霍尔控制模式,若否,判断霍尔传感器故障,并控制电机切换为反电动势控制模式。本发明通过对各霍尔传感器连续实时输出信号信号值大小的比较,从而及时获取霍尔传感器故障信息,通过反电动势零点检测对电流方向进行切换,从而保证柱塞泵能够以正常的力学特性运转。(The invention discloses a composite control method and a composite control system based on a Hall sensor motor, which relate to the field of motor control and specifically comprise the following steps: acquiring continuous real-time output signals of all Hall sensors; and judging whether the output signal at the current acquisition moment is consistent with the output signal at the previous acquisition moment, if so, controlling the motor to keep a Hall control mode, otherwise, judging the fault of the Hall sensor, and controlling the motor to be switched into a back electromotive force control mode. According to the invention, through comparison of the signal values of the continuous real-time output signals of the Hall sensors, the fault information of the Hall sensors is obtained in time, and the current direction is switched through the back electromotive force zero point detection, so that the plunger pump can be ensured to operate with normal mechanical characteristics.)

1. A composite control method based on a Hall sensor motor is characterized by comprising the following steps:

s1: acquiring continuous real-time output signals of all Hall sensors;

s2: judging whether the output signal of the current acquisition time is consistent with the output signal of the previous acquisition time, if so, controlling the motor to keep a Hall control mode, if not, judging the fault of the Hall sensor, and entering the step S3;

s3: the control motor is switched to a back electromotive force control mode.

2. The hall sensor motor-based compound control method of claim 1, wherein in step S2, the hall control mode is:

and calculating the angular position of the current rotor and a preset coordinate axis according to the real-time output signal, and controlling the motor rotor according to the angular position.

3. The hall sensor motor-based composite control method of claim 2, wherein each angular position corresponds to a different distribution interval, each step interval is provided with a preset angular extremum, and the specific way of controlling the motor rotor according to the angular position is as follows:

when the angle position reaches a preset angle extreme value in a certain distribution interval, the Hall sensor output signals in the corresponding step intervals control current commutation.

4. The hall sensor motor-based compound control method of claim 1, wherein in the step S3, the back electromotive force control mode is:

and when the port voltage of the unpowered phase group is a half value of the bus voltage, the collection time is taken as the back electromotive force zero time, and the motor rotor is controlled according to the zero time.

5. The composite control method based on the hall sensor motor according to claim 1, wherein the specific way of controlling the motor rotor according to the zero point moment is as follows:

when the zero moment of the back electromotive force is reached, the current is controlled to be commutated.

6. A combined control system based on a Hall sensor motor is characterized by comprising:

the signal collector is used for collecting continuous real-time output signals of all the Hall sensors;

the fault judger is used for outputting a fault signal when the output signal at the current acquisition moment is inconsistent with the output signal at the previous acquisition moment;

and the mode switcher is used for controlling the motor to be switched into a back electromotive force control mode when receiving the fault signal, and otherwise, controlling the motor to keep the Hall control mode.

7. The hall sensor motor based compound control system of claim 6 wherein the hall control pattern is:

and calculating the angular position of the current rotor and a preset coordinate axis according to the real-time output signal, and controlling the motor rotor according to the angular position.

8. The hall sensor motor-based compound control system as claimed in claim 7, wherein each angular position corresponds to a different distribution interval, each step interval is provided with a preset angular extremum, and the control of the motor rotor according to the angular position is performed by:

when the angle position reaches a preset angle extreme value in a certain distribution interval, the Hall sensor output signals in the corresponding step intervals control current commutation.

9. The hall sensor motor based compound control system of claim 6 wherein the back emf control mode is:

and when the port voltage of the unpowered phase group is a half value of the bus voltage, the collection time is taken as the back electromotive force zero time, and the motor rotor is controlled according to the zero time.

10. The hall sensor motor-based composite control system of claim 9, wherein the specific way to control the motor rotor according to the zero point moment is:

when the zero moment of the back electromotive force is reached, the current is controlled to be commutated.

Technical Field

The invention relates to the field of motor control, in particular to a composite control method and a composite control system based on a Hall sensor motor.

Background

Generally, a brushless dc motor of a plunger pump uses a relatively simple motor position sensor, and in the prior art, a hall sensor is used to perform field-oriented control of the motor for cost reduction. However, in some emergency situations, a large error exists in the output angle calculation result due to the failure of the hall sensor, and if the plunger pump is operated under the error, the mechanical property of the plunger pump is greatly influenced. Therefore, the problem to be solved by the invention is how to find the fault of the Hall sensor in time and take corresponding measures to ensure the normal operation of the plunger pump when the fault occurs.

Disclosure of Invention

In order to solve the problem that a plunger pump based on a Hall sensor driving motor can still keep running with better mechanical property under the condition of sudden failure of the Hall sensor, the invention provides a composite control method based on the Hall sensor motor, which comprises the following steps:

s1: acquiring continuous real-time output signals of all Hall sensors;

s2: judging whether the output signal of the current acquisition time is consistent with the output signal of the previous acquisition time, if so, controlling the motor to keep a Hall control mode, if not, judging the fault of the Hall sensor, and entering the step S3;

s3: the control motor is switched to a back electromotive force control mode.

Further, in step S2, the hall control mode is:

and calculating the angular position of the current rotor and a preset coordinate axis according to the real-time output signal, and controlling the motor rotor according to the angular position.

Further, each angle position corresponds to a different distribution interval, each step interval is provided with a preset angle extreme value, and the specific mode of controlling the motor rotor according to the angle position is as follows:

when the angle position reaches a preset angle extreme value in a certain distribution interval, the Hall sensor output signals in the corresponding step intervals control current commutation.

Further, in step S3, the back electromotive force control mode is:

and when the port voltage of the unpowered phase group is a half value of the bus voltage, the collection time is taken as the back electromotive force zero time, and the motor rotor is controlled according to the zero time.

Further, the specific way of controlling the motor rotor according to the zero point time is as follows:

when the zero moment of the back electromotive force is reached, the current is controlled to be commutated.

The invention also provides a combined control system based on the Hall sensor motor, which comprises:

the signal collector is used for collecting continuous real-time output signals of all the Hall sensors;

the fault judger is used for outputting a fault signal when the output signal at the current acquisition moment is inconsistent with the output signal at the previous acquisition moment;

and the mode switcher is used for controlling the motor to be switched into a back electromotive force control mode when receiving the fault signal, and otherwise, controlling the motor to keep the Hall control mode.

Further, the hall control mode is:

and calculating the angular position of the current rotor and a preset coordinate axis according to the real-time output signal, and controlling the motor rotor according to the angular position.

Further, each angle position corresponds to a different distribution interval, each step interval is provided with a preset angle extreme value, and the specific mode of controlling the motor rotor according to the angle position is as follows:

when the angle position reaches a preset angle extreme value in a certain distribution interval, the Hall sensor output signals in the corresponding step intervals control current commutation.

Further, the back electromotive force control mode is as follows:

and when the port voltage of the unpowered phase group is a half value of the bus voltage, the collection time is taken as the back electromotive force zero time, and the motor rotor is controlled according to the zero time.

Further, the specific way of controlling the motor rotor according to the zero point time is as follows:

when the zero moment of the back electromotive force is reached, the current is controlled to be commutated.

Compared with the prior art, the invention at least has the following beneficial effects:

(1) according to the combined control method and system based on the Hall sensor motor, the Hall sensor fault information is obtained in time by comparing the signal values of the continuous real-time output signals of the Hall sensors;

(2) when the Hall sensor breaks down, the current direction is switched through the detection of the back electromotive force zero point, so that the plunger pump can be ensured to operate with normal mechanical characteristics.

Drawings

FIG. 1 is a method step diagram of a Hall sensor motor based compound control method and system;

FIG. 2 is a system structure diagram of a hall sensor motor based compound control method and system;

FIG. 3 is a schematic diagram of a three Hall sensor motor;

FIG. 4 is a schematic diagram of a current signal;

FIG. 5 is a schematic diagram of a square wave air gap magnetic field and a trapezoidal wave back emf.

Detailed Description

The following are specific embodiments of the present invention and are further described with reference to the drawings, but the present invention is not limited to these embodiments.

Example one

In order to solve the problem that a plunger pump based on a Hall sensor driving motor can still keep running with better mechanical property under the condition of sudden failure of the Hall sensor, as shown in figure 1, the invention provides a composite control method based on the Hall sensor motor, which comprises the following steps:

s1: acquiring continuous real-time output signals of all Hall sensors;

s2: judging whether the output signal of the current acquisition time is consistent with the output signal of the previous acquisition time, if so, controlling the motor to keep a Hall control mode, if not, judging the fault of the Hall sensor, and entering the step S3;

s3: the control motor is switched to a back electromotive force control mode.

According to the method, when the motor runs, the Hall sensor is firstly subjected to fault diagnosis, and the Hall sensor with the fault can be immediately detected at the first moment when the Hall sensor has the fault and the peak value of the output signal changes through comparing the continuous real-time output signals, so that the driving mode of the motor is switched.

In step S2, determining whether any hall sensor in the hall sensor group in the electrical apparatus has failed includes:

continuously sampling the signal values output by the Hall sensor group, wherein the continuous sampling refers to collecting and processing signals acquired by the Hall sensors each time;

comparing the signal values output by the hall sensor group twice in succession, generally, the interval between two adjacent output signals of each hall sensor is 200 microseconds, of course, it can also be 100 microseconds, 300 microseconds or other time, the numerical values listed here are not limited to the range, and only an example is given;

if the signal values output twice are the same, judging that the Hall sensor group does not have a fault; and if the signal values output twice are different, judging that the Hall sensor group has a fault.

In step S2, the hall control mode is to calculate the angular position between the current rotor and a preset coordinate axis (which can be set by the user as required) according to the real-time output signal, and control the motor rotor according to the angular position.

Taking a three-Hall sensor motor as an example, the circumferential area where the stator is located is equally divided into 6 step intervals U1, U2, U3, U4, U5 and U6 according to the three Hall sensors. When the magnetic poles of the motor rotor are positioned in different step intervals, the Hall sensor groups output different signal values Y1, Y2, Y3, Y4, Y5 and Y6; wherein, each signal value corresponds to an angle range (R61-R12), (R12-R23), (R23-R34), (R34-R45), (R45-R56) and (R56-R61). The specific mode of controlling the motor rotor according to the angle is as follows:

and calculating an extreme value alpha of the angle between the rotor and the preset coordinate axis. Wherein, the extreme value α is calculated as follows:

if the signal value jumps from Y1 to Y2, the extreme value is R12;

if the signal value jumps from Y2 to Y3, the extreme value is R23;

if the signal value jumps from Y3 to Y4, the extreme value is R34;

if the signal value jumps from Y4 to Y5, the extreme value is R45;

if the signal value jumps from Y5 to Y6, the extreme value is R56;

if the signal value jumps from Y6 to Y1, the extreme value is R61;

as shown in fig. 3, a hall sensor is installed on a permanent magnet synchronous motor, wherein A, B, C devices are three hall sensors, which are fixed on a stator and do not follow the rotation of a motor rotor. The rotor of the synchronous motor is marked N-S, and when the magnetic pole fixed on the rotor rotates together with the rotor and approaches the hall sensor, it induces current on the sensor, thereby outputting a high level signal, and when the magnetic pole fixed on the rotor is farther from the hall sensor, the induced current disappears, thereby outputting a low level signal. Thus, when the rotor magnetic poles rotate, high and low current signals shown in fig. 4 are induced on A, B, C three hall sensors. The X axis of a coordinate system is fixed on the stator and is on the same straight line with the Hall sensor B, the included angle between the N axis and the X axis of the rotor magnetic pole is set as the included angle alpha which needs to be calculated, the method plays a key role in vector control of the motor, and when the angle position reaches a preset angle extreme value in a certain distribution interval, the Hall sensor output signal in the corresponding step interval controls current commutation.

Meanwhile, fig. 5 (in the figure, Bm is the magnetic field strength, Em is the electric field strength) shows the square wave air gap magnetic field and the trapezoidal wave back electromotive force in the normal working time of the dc brushless motor. When the counter potential of a certain phase winding of the DC brushless motor is zero, the straight axis of the rotor is just coincided with the axis of the phase winding. Therefore, as long as the zero crossing of the counter electromotive force of each phase winding is detected, a plurality of key positions of the rotor can be obtained. And then according to the key rotor position signals, performing corresponding treatment and controlling the motor to change phases to realize continuous operation, namely the control of the DC brushless motor by a counter-electromotive force method.

Through analysis of a mathematical model of the direct current brushless motor, the terminal voltage of the non-electrified phase is equal to the neutral point voltage at the back electromotive force zero-crossing moment during the electrifying period of the two-phase winding of the motor. When the bus voltage is supplied with direct current, and a certain two-phase winding is electrified, the neutral point voltage is half of the bus voltage.

And taking half of the bus voltage pair as a reference value, comparing the reference voltage with the terminal voltage of the unpowered phase winding by using corresponding equipment, and obtaining the zero crossing time of the back electromotive force when the reference voltage is equal to the terminal voltage of the unpowered phase winding. When the zero moment of the back electromotive force is reached, the current is controlled to be commutated.

It can be seen from fig. 5 that ω t is 30 ° in electrical angle, which is the time at which the opposite potential crosses zero. When the control circuit detects the moment, the electric angle is delayed by 30 degrees, and the A phase is switched to be conducted when the electric angle reaches 60 degrees. And after the phase A is conducted by 120 degrees of electrical angle, the phase A is turned off when the electrical angle reaches 180 degrees, and the phase A is switched to be conducted by the phase B. By analogy, the continuous operation of the motor can be realized, and the optimal commutation logic is met.

By adopting the motor control method, when the motor runs, the fault diagnosis is firstly carried out on the Hall sensor, and the accuracy and the credibility of the calculated angle position are ensured. The angular error in the manufacturing and installation process is corrected by the compensation amount in consideration of the manufacturing error of the hall sensor. Under the condition that the Hall sensors are normal, the accurate angular position of the rotor on the whole circumference is obtained by estimating the angular speed and the angular acceleration of the rotor of the motor. When the Hall sensor fails, a back electromotive force method is adopted for motor control, and the plunger pump can be ensured to continue to work under some emergency conditions.

Example two

In order to better describe the technical content of the present invention, the present embodiment describes the module of the present invention in a form of a system structure, as shown in fig. 2, a hall sensor motor-based compound control system includes:

the signal collector is used for collecting continuous real-time output signals of all Hall sensors (arranged in the motor);

the fault judger is used for outputting a fault signal when the output signal at the current acquisition moment is inconsistent with the output signal at the previous acquisition moment;

and the mode switcher is used for controlling the motor to be switched into a back electromotive force control mode when receiving the fault signal, and otherwise, controlling the motor to keep the Hall control mode.

Further, the hall control mode is:

and calculating the angular position of the current rotor and a preset coordinate axis according to the real-time output signal, and controlling the motor rotor according to the angular position.

Further, each angle position corresponds to a different distribution interval, each step interval is provided with a preset angle extreme value, and the specific mode of controlling the motor rotor according to the angle position is as follows:

when the angle position reaches a preset angle extreme value in a certain distribution interval, the Hall sensor output signals in the corresponding step intervals control current commutation.

Further, the back electromotive force control mode is as follows:

and when the port voltage of the unpowered phase group is a half value of the bus voltage, the collection time is taken as the back electromotive force zero time, and the motor rotor is controlled according to the zero time.

Further, the specific way of controlling the motor rotor according to the zero point time is as follows:

when the zero moment of the back electromotive force is reached, the current is controlled to be commutated.

In summary, according to the combined control method and system based on the hall sensor motor, the hall sensor fault information is obtained in time by comparing the signal values of the continuous real-time output signals of the hall sensors.

When the Hall sensor breaks down, the current direction is switched through the detection of the back electromotive force zero point, so that the plunger pump can be ensured to operate with normal mechanical characteristics.

It should be noted that all the directional indicators (such as up, down, left, right, front, and rear … …) in the embodiment of the present invention are only used to explain the relative position relationship between the components, the movement situation, etc. in a specific posture (as shown in the drawing), and if the specific posture is changed, the directional indicator is changed accordingly.

Moreover, descriptions of the present invention as relating to "first," "second," "a," etc. are for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicit ly indicating a number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "a plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise.

In the present invention, unless otherwise expressly stated or limited, the terms "connected," "secured," and the like are to be construed broadly, and for example, "secured" may be a fixed connection, a removable connection, or an integral part; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or they may be connected internally or in any other suitable relationship, unless expressly stated otherwise. 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 addition, the technical solutions in the embodiments of the present invention may be combined with each other, but it must be based on the realization of those skilled in the art, and when the technical solutions are contradictory or cannot be realized, such a combination of technical solutions should not be considered to exist, and is not within the protection scope of the present invention.

The specific embodiments described herein are merely illustrative of the spirit of the invention. Various modifications or additions may be made to the described embodiments or alternatives may be employed by those skilled in the art without departing from the spirit or ambit of the invention as defined in the appended claims.