阅读说明：本技术 一种永磁电机电压自适应控制系统及方法 (Permanent magnet motor voltage self-adaptive control system and method ) 是由 徐衍亮 王梓鉴 于川皓 于文涛 闫敬东 张文清 于治华 马文忠 于 2020-08-10 设计创作，主要内容包括：本发明提供一种永磁电机电压自适应控制系统及方法,包括：控制装置、三组三相供电电源、三相变压器以及永磁电机；三相变压器的次级线圈通过控制装置中的继电器和控制开关连接永磁电机,控制永磁电机运行。本发明采用了双绕组补偿变压器,对其绕组进行正反串接来实现多档电压,具有配置容量小、运行损耗小、不产生任何谐波等显著优点,控制装置实现自动检测,自动控制的运行方式。控制装置实现对永磁电机的各种输入数据进行计算处理,并根据计算结果诊断出永磁电机当前的运行状态,自动调节输出电压,依次实现自动监测、自动跟踪、自动调控,为永磁电机提供最佳的运行电压,确保抽油机永磁电机始终处于高效经济运行状态。(The invention provides a permanent magnet motor voltage self-adaptive control system and a permanent magnet motor voltage self-adaptive control method, which comprise the following steps: the system comprises a control device, three groups of three-phase power supplies, a three-phase transformer and a permanent magnet motor; and a secondary coil of the three-phase transformer is connected with the permanent magnet motor through a relay and a control switch in the control device to control the permanent magnet motor to operate. The invention adopts the double-winding compensation transformer, realizes multi-gear voltage by carrying out positive and negative serial connection on the windings of the double-winding compensation transformer, has the obvious advantages of small configuration capacity, small running loss, no generation of any harmonic wave and the like, and realizes the running mode of automatic detection and automatic control by the control device. The control device realizes calculation processing of various input data of the permanent magnet motor, diagnoses the current running state of the permanent magnet motor according to the calculation result, automatically adjusts output voltage, sequentially realizes automatic monitoring, automatic tracking and automatic regulation, provides optimal running voltage for the permanent magnet motor, and ensures that the permanent magnet motor of the oil pumping unit is always in an efficient and economic running state.)

1. A permanent magnet motor voltage adaptive control system, comprising: the device comprises a control device, a three-phase power supply, a three-phase transformer and a permanent magnet motor;

the primary coil of the three-phase transformer is connected with a three-phase power supply;

each phase of the secondary coil of the three-phase transformer is electrically provided with N gears;

the control device is provided with three-phase power supply circuits the number of which is the same as that of the gears of the secondary coils of the three-phase transformer;

the input end of each phase of electricity in the three-phase power supply line is correspondingly connected with the three-phase electricity of the secondary coil of the three-phase transformer; the output end of each phase of electricity in the three-phase power supply circuit is connected with the permanent magnet motor;

an upper connection switch is respectively arranged in each three-phase power supply circuit; wherein, two three-phase power supply lines are respectively provided with a lower connection switch, and the three-phase power supply line provided with the lower connection switch is a three-phase selection power supply line;

an upper connection switch and a lower connection switch in the three-phase selection power supply line are connected in series; the upper connection switch and the lower connection switch in the same three-phase selective power supply line are not closed at the same time, and the lower connection switch is synchronously closed with the upper connection switch in the non-three-phase selective power supply line according to a control instruction to supply power to the permanent magnet motor.

2. The permanent magnet motor voltage adaptive control system according to claim 1,

the control device is also provided with a manual three-phase power supply circuit;

a manual control switch KM6 is arranged on the manual three-phase power supply line, the first end of the manual three-phase power supply line is connected with a three-phase power supply through a primary coil of a three-phase transformer, and the second end of the manual three-phase power supply line is connected with a permanent magnet motor.

3. The permanent magnet motor voltage adaptive control system according to claim 1,

the secondary coil of the three-phase transformer is provided with three groups of secondary taps to form three gears;

the control device is provided with three-phase power supply circuits;

the first three-phase power supply line is provided with a first three-phase control switch KM1 and a fourth three-phase control switch KM 4;

the second three-phase power supply line is provided with a second three-phase control switch KM 2;

the third three-phase power supply line is provided with a third three-phase control switch KM3 and a fifth three-phase control switch KM 5;

the first three-phase control switch KM1, the second three-phase control switch KM2 and the third three-phase control switch KM3 are all upper-connected switches;

the fourth three-phase control switch KM4 and the fifth three-phase control switch KM5 are both connected switches;

according to the control instruction, the second three-phase control switch KM2 or the third three-phase control switch KM3 and the fourth three-phase control switch KM4 respectively form two permanent magnet motor control gears;

the first three-phase control switch KM1 or the second three-phase control switch KM2 and the fifth three-phase control switch KM5 form two permanent magnet motor control gears.

4. The permanent magnet motor voltage adaptive control system according to claim 1,

the secondary coil of the three-phase transformer is provided with four groups of secondary taps to form four gears;

the control device is provided with four three-phase power supply circuits;

the first three-phase power supply line is provided with a first three-phase control switch KM1 and a fourth three-phase control switch KM 4;

the second three-phase power supply line is provided with a second three-phase control switch KM 2;

the third three-phase power supply line is provided with a third three-phase control switch KM3 and a fifth three-phase control switch KM 5;

a seventh three-phase control switch KM7 is arranged on the fourth three-phase power supply line;

the seventh three-phase control switch KM7, the first three-phase control switch KM1, the second three-phase control switch KM2 and the third three-phase control switch KM3 are upper-connected switches;

the fourth three-phase control switch KM4 and the fifth three-phase control switch KM5 are both connected switches;

according to the control instruction, the seventh three-phase control switch KM7, the second three-phase control switch KM2, or the third three-phase control switch KM3 and the fourth three-phase control switch KM4 form three permanent magnet motor control gears respectively;

the seventh three-phase control switch KM7, or the first three-phase control switch KM1, or the second three-phase control switch KM2 respectively form three permanent magnet motor control gears with the fifth three-phase control switch KM 5.

5. The permanent magnet motor voltage adaptive control system according to claim 1,

the secondary coil of the three-phase transformer is provided with two groups of secondary taps to form two gears;

the control device is provided with two three-phase power supply circuits;

the first three-phase power supply line is provided with a first three-phase control switch KM1 and a fourth three-phase control switch KM 4;

the second three-phase power supply line is provided with a third three-phase control switch KM3 and a fifth three-phase control switch KM 5;

the first three-phase control switch KM1 and the third three-phase control switch KM3 are both upper-connected switches;

the fourth three-phase control switch KM4 and the fifth three-phase control switch KM5 are both connected switches;

according to the control instruction, the third three-phase control switch KM3 and the fourth three-phase control switch KM4 form a permanent magnet motor control gear;

the first three-phase control switch KM1 and the fifth three-phase control switch KM5 form a permanent magnet motor control gear.

6. The permanent magnet motor voltage adaptive control system according to claim 1,

the control device is also provided with a control instruction acquisition module, a control module and a parameter setting module;

the control instruction acquisition module and the parameter setting module are respectively in communication connection with the control module;

the control module acquires system preset parameters through the parameter setting module;

setting a secondary voltage grade E1 of the transformer to be 10-99V; e2 ═ 10-99 volts;

setting a primary voltage gear Ue of the transformer as 300-700V;

setting the startup voltage drop Uf to 10-60 volts;

setting the no-load counter potential E0 to 300-730V;

the control module acquires a control instruction input by a user or a parameter preset by the system through the control instruction acquisition module, and controls the action of the upper link switch and the lower link switch to realize the gear switching of the power supply of the permanent magnet motor.

7. The permanent magnet motor voltage adaptive control system according to claim 3,

the control module detects the power supply voltage U in real time;

presetting UL as U;

the control module respectively calculates values of ER1, ER2, ER3, ER4 and ER5 according to the following formula;

ER1＝UL(KM6)

according to a control gear command input by a user, selecting the corresponding ER1, or ER2, or ER3, or ER4, or ER5 gear during starting, and starting the permanent magnet motor;

acquiring current gear data in real time in the operation process, and enabling the current gear data to exceed a preset range;

the preset range is that E0-E is less than or equal to E0+ E/2;

executing gear shifting operation and replacing other gear data;

the control module executes gear shifting operation, and whether the value of each current gear ER1, ER2, ER3, ER4 and ER5 is in a preset range or not is acquired through E0-E < (ER1 or ER2 or ER3 or ER4 or ER5) < E0+ E/2; and if a certain gear is in a preset range and the currently selected gear ER is equal to E0, changing the current gear into the gear.

8. The permanent magnet motor voltage adaptive control system according to claim 7,

after the control module determines the gear shifting position, whether the manual control switch KM6 is disconnected or not is judged, if the manual control switch KM6 is not disconnected, after the preset time delay, gear shifting operation is executed, and the action of a three-phase control switch corresponding to the gear shifting position is controlled;

further comprising: three groups of three-phase power supplies;

the first phase of each group of three-phase power supply is connected with a first primary phase tap of the primary coil of the three-phase transformer;

the second phase of each group of three-phase power supply is connected with a second primary phase tap of the primary coil of the three-phase transformer;

and the third phase of each group of three-phase power supply is connected with a third primary phase tap of the primary coil of the three-phase transformer.

9. A permanent magnet motor voltage adaptive control method, characterized in that the permanent magnet motor voltage adaptive control system according to any one of claims 1 to 8 is adopted;

the method comprises the following steps:

closing a power supply and powering on a system;

acquiring a starting control instruction, selecting a corresponding gear during starting according to a gear control instruction input by a user, and controlling the starting permanent magnet motor to operate;

acquiring current gear data in real time in the running process of the permanent magnet motor, comparing the current gear data with a preset range, and judging whether a threshold value is exceeded or not;

if the current gear exceeds the threshold value, executing gear shifting operation, and replacing other gear data;

executing a gear shifting operation, and acquiring whether the value of each current gear ER1, ER2, ER3, ER4 and ER5 is in a preset range or not through E0-E < (ER1 or ER2 or ER3 or ER4 or ER5) < E0+ E/2;

if a certain gear is in a preset range and the currently selected gear ER value is E0, judging whether the manual control switch KM6 is disconnected or not, if the manual control switch KM6 is not disconnected, disconnecting the manual control switch KM6, and after delaying for a preset time, executing a gear shifting operation and controlling the action of the three-phase control switch corresponding to the gear shifting position.

10. The adaptive control method for the voltage of the permanent magnet motor according to claim 9,

when the gear shifting operation is executed, the lower connection switch is firstly disconnected when the three-phase control switch corresponding to the original gear is disconnected; then the upper connection switch is disconnected;

when the three-phase control switch corresponding to the original gear is closed, the upper-connection switch is closed first, and then the lower-connection switch is closed.

Technical Field

The invention relates to the technical field of permanent magnet motors, in particular to a permanent magnet motor voltage self-adaptive control system and method.

Background

The permanent magnet motor has the advantages of high efficiency, good electricity-saving effect and the like, and theoretically has a high power factor approximately equal to 1. At present, the oil pumping unit is rapidly popularized and applied to oil field pumping units. Compared with a three-phase asynchronous motor, although typical engineering test results of a permanent magnet motor which is widely popularized are very encouraging, large-area tracking tests find that the power factor of more than half of the permanent magnet motor is below 0.5, and the energy consumption is close to that of the asynchronous motor. The power factor of the permanent magnet motor is close to 1, which is an important basis for replacing the energy-saving modification of an asynchronous motor, and if the running power factor of the permanent magnet motor is too low, the replacement value and the advantages of the permanent magnet motor are lost. In addition, long-term tracking test researches show that the mechanical structure of the oil pumping unit cannot be changed, the load factor of the motor cannot be improved, and the permanent magnet motor can be demagnetized after being used for a long time, so that the problem severity is further aggravated. More than half of oil field permanent magnet motors can not achieve due energy-saving effect, the performance is close to that of asynchronous motors, and an embarrassed chicken rib situation that the food is tasteless and can be forgotten is formed, so that the development of the oil field energy-saving industry is seriously limited, and huge manpower, material resources and financial resources are consumed and wasted.

Disclosure of Invention

In order to overcome the defects in the prior art, the invention provides a permanent magnet motor voltage self-adaptive control system, which comprises: the device comprises a control device, a three-phase power supply, a three-phase transformer and a permanent magnet motor;

the primary coil of the three-phase transformer is connected with a three-phase power supply;

each phase of the secondary coil of the three-phase transformer is electrically provided with N gears;

the control device is provided with three-phase power supply circuits the number of which is the same as that of the gears of the secondary coils of the three-phase transformer;

the input end of each phase of electricity in the three-phase power supply line is correspondingly connected with the three-phase electricity of the secondary coil of the three-phase transformer; the output end of each phase of electricity in the three-phase power supply circuit is connected with the permanent magnet motor;

an upper connection switch is respectively arranged in each three-phase power supply circuit; wherein, two three-phase power supply lines are respectively provided with a lower connection switch, and the three-phase power supply line provided with the lower connection switch is a three-phase selection power supply line;

an upper connection switch and a lower connection switch in the three-phase selection power supply line are connected in series; the upper connection switch and the lower connection switch in the same three-phase selective power supply line are not closed at the same time, and the lower connection switch is synchronously closed with the upper connection switch in the non-three-phase selective power supply line according to a control instruction to supply power to the permanent magnet motor.

Preferably, the control device is also provided with a manual three-phase power supply circuit;

a manual control switch KM6 is arranged on the manual three-phase power supply line, the first end of the manual three-phase power supply line is connected with a three-phase power supply through a primary coil of a three-phase transformer, and the second end of the manual three-phase power supply line is connected with a permanent magnet motor.

Preferably, the secondary coil of the three-phase transformer is provided with three groups of secondary taps to form three gears;

the control device is provided with three-phase power supply circuits;

the first three-phase power supply line is provided with a first three-phase control switch KM1 and a fourth three-phase control switch KM 4;

the second three-phase power supply line is provided with a second three-phase control switch KM 2;

the third three-phase power supply line is provided with a third three-phase control switch KM3 and a fifth three-phase control switch KM 5;

the first three-phase control switch KM1, the second three-phase control switch KM2 and the third three-phase control switch KM3 are all upper-connected switches;

the fourth three-phase control switch KM4 and the fifth three-phase control switch KM5 are both connected switches;

according to the control instruction, the second three-phase control switch KM2 or the third three-phase control switch KM3 and the fourth three-phase control switch KM4 respectively form two permanent magnet motor control gears;

the first three-phase control switch KM1 or the second three-phase control switch KM2 and the fifth three-phase control switch KM5 form two permanent magnet motor control gears.

Preferably, the secondary coil of the three-phase transformer is provided with four groups of secondary taps to form four gears;

the control device is provided with four three-phase power supply circuits;

the first three-phase power supply line is provided with a first three-phase control switch KM1 and a fourth three-phase control switch KM 4;

the second three-phase power supply line is provided with a second three-phase control switch KM 2;

the third three-phase power supply line is provided with a third three-phase control switch KM3 and a fifth three-phase control switch KM 5;

a seventh three-phase control switch KM7 is arranged on the fourth three-phase power supply line;

the seventh three-phase control switch KM7, the first three-phase control switch KM1, the second three-phase control switch KM2 and the third three-phase control switch KM3 are upper-connected switches;

the fourth three-phase control switch KM4 and the fifth three-phase control switch KM5 are both connected switches;

according to the control instruction, the seventh three-phase control switch KM7, the second three-phase control switch KM2, or the third three-phase control switch KM3 and the fourth three-phase control switch KM4 form three permanent magnet motor control gears respectively;

the seventh three-phase control switch KM7, or the first three-phase control switch KM1, or the second three-phase control switch KM2 respectively form three permanent magnet motor control gears with the fifth three-phase control switch KM 5.

Preferably, the secondary coil of the three-phase transformer is provided with two groups of secondary taps to form two gears;

the control device is provided with two three-phase power supply circuits;

the first three-phase power supply line is provided with a first three-phase control switch KM1 and a fourth three-phase control switch KM 4;

the second three-phase power supply line is provided with a third three-phase control switch KM3 and a fifth three-phase control switch KM 5;

the first three-phase control switch KM1 and the third three-phase control switch KM3 are both upper-connected switches;

the fourth three-phase control switch KM4 and the fifth three-phase control switch KM5 are both connected switches;

according to the control instruction, the third three-phase control switch KM3 and the fourth three-phase control switch KM4 form a permanent magnet motor control gear;

the first three-phase control switch KM1 and the fifth three-phase control switch KM5 form a permanent magnet motor control gear.

Preferably, the control device is also provided with a control instruction acquisition module, a control module and a parameter setting module;

the control instruction acquisition module and the parameter setting module are respectively in communication connection with the control module;

the control module acquires system preset parameters through the parameter setting module;

setting a secondary voltage grade E1 of the transformer to be 10-99V; e2 ═ 10-99 volts;

setting a primary voltage gear Ue of the transformer as 300-700V;

setting the startup voltage drop Uf to 10-60 volts;

setting the no-load counter potential E0 to 300-730V;

the control module acquires a control instruction input by a user or a parameter preset by the system through the control instruction acquisition module, and controls the action of the upper link switch and the lower link switch to realize the gear switching of the power supply of the permanent magnet motor.

Preferably, the control module detects the power supply voltage U in real time;

presetting UL as U;

the control module respectively calculates values of ER1, ER2, ER3, ER4 and ER5 according to the following formula;

ER1＝UL (KM6)

according to a control gear command input by a user, selecting the corresponding ER1, or ER2, or ER3, or ER4, or ER5 gear during starting, and starting the permanent magnet motor;

acquiring current gear data in real time in the operation process, and enabling the current gear data to exceed a preset range;

the preset range is that E0-E is less than or equal to E0+ E/2;

executing gear shifting operation and replacing other gear data;

the control module executes gear shifting operation, and whether the value of each current gear ER1, ER2, ER3, ER4 and ER5 is in a preset range or not is acquired through E0-E < (ER1 or ER2 or ER3 or ER4 or ER5) < E0+ E/2; and if a certain gear is in a preset range and the currently selected gear ER is equal to E0, changing the current gear into the gear.

Preferably, after the control module determines the shift position, the control module determines whether the manual control switch KM6 is turned off, if not, the control module turns off the manual control switch KM6, after delaying for a preset time, performs the shift operation, and controls the three-phase control switch corresponding to the shift position to act;

further comprising: three groups of three-phase power supplies;

the first phase of each group of three-phase power supply is connected with a first primary phase tap of the primary coil of the three-phase transformer;

the second phase of each group of three-phase power supply is connected with a second primary phase tap of the primary coil of the three-phase transformer;

and the third phase of each group of three-phase power supply is connected with a third primary phase tap of the primary coil of the three-phase transformer.

The invention also provides a permanent magnet motor voltage self-adaptive control method, which comprises the following steps:

closing a power supply and powering on a system;

acquiring a starting control instruction, selecting a corresponding gear during starting according to a gear control instruction input by a user, and controlling the starting permanent magnet motor to operate;

acquiring current gear data in real time in the running process of the permanent magnet motor, comparing the current gear data with a preset range, and judging whether a threshold value is exceeded or not;

if the current gear exceeds the threshold value, executing gear shifting operation, and replacing other gear data;

executing a gear shifting operation, and acquiring whether the value of each current gear ER1, ER2, ER3, ER4 and ER5 is in a preset range or not through E0-E < (ER1 or ER2 or ER3 or ER4 or ER5) < E0+ E/2;

if a certain gear is in a preset range and the currently selected gear ER value is E0, judging whether the manual control switch KM6 is disconnected or not, if the manual control switch KM6 is not disconnected, disconnecting the manual control switch KM6, and after delaying for a preset time, executing a gear shifting operation and controlling the action of the three-phase control switch corresponding to the gear shifting position.

When the gear shifting operation is executed, the lower connection switch is firstly disconnected when the three-phase control switch corresponding to the original gear is disconnected; then the upper connection switch is disconnected;

when the three-phase control switch corresponding to the original gear is closed, the upper-connection switch is closed first, and then the lower-connection switch is closed.

According to the technical scheme, the invention has the following advantages:

the invention dynamically controls the permanent magnet motor of the existing oil pumping unit in the oil field, and if the operation power factor is lower, the voltage self-adaptive control method and the system of the permanent magnet motor can be applied to dynamically switch the gear operation in real time, thereby ensuring the efficient and economic operation of the permanent magnet motor.

The invention adopts the double-winding compensation transformer, realizes multi-gear voltage by connecting the windings in series, has the obvious advantages of small configuration capacity, small running loss, low manufacturing cost, static voltage regulation of the original ecological transformer, no generation of any harmonic wave and the like, and the control device realizes the running mode of automatic detection and automatic control. The operation process of field operation maintenance personnel is simplified. The control device realizes calculation processing of various input data of the permanent magnet motor, diagnoses the current running state of the permanent magnet motor according to the calculation result, automatically adjusts output voltage, sequentially realizes automatic monitoring, automatic tracking and automatic regulation, provides optimal running voltage for the permanent magnet motor, and ensures that the permanent magnet motor of the oil pumping unit is always in an efficient and economic running state.

The system controls the permanent magnet motor of the existing pumping unit in the oil field, so that the operating power factor of the pumping unit can be always kept above 0.97, and the comprehensive power saving rate can be up to above 20%.

Drawings

In order to more clearly illustrate the technical solution of the present invention, the drawings used in the description will be briefly introduced, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained based on these drawings without creative efforts.

FIG. 1 is a schematic diagram of a permanent magnet motor voltage adaptive control system;

FIG. 2 is a schematic diagram of an embodiment of a permanent magnet motor voltage adaptive control system for controlling five gears;

fig. 3 is a schematic diagram of a seventh-gear control embodiment of the adaptive control system for permanent magnet motor voltage.

Detailed Description

Those of ordinary skill in the art will appreciate that the elements and algorithm steps of the examples described in connection with the embodiments disclosed herein may be embodied in electronic hardware, computer software, or combinations of both, and that the components and steps of the examples have been described in a functional general in the foregoing description for the purpose of illustrating clearly the interchangeability of hardware and software. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the implementation. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present invention.

The block diagrams shown in the figures are functional entities only and do not necessarily correspond to physically separate entities. I.e. these functional entities may be implemented in the form of software, or in one or more hardware modules or integrated circuits, or in different networks and/or processor means and/or microcontroller means.

In the several embodiments provided in the present application, it should be understood that the disclosed system, apparatus and method may be implemented in other ways. For example, the above-described apparatus embodiments are merely illustrative, and for example, the division of the units is only one logical division, and other divisions may be realized in practice, for example, a plurality of units or components may be combined or integrated into another system, or some features may be omitted, or not executed. In addition, the shown or discussed mutual coupling or direct coupling or communication connection may be an indirect coupling or communication connection through some interfaces, devices or units, and may also be an electric, mechanical or other form of connection.

Furthermore, the described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. In the following description, numerous specific details are provided to provide a thorough understanding of embodiments of the invention. One skilled in the relevant art will recognize, however, that the invention may be practiced without one or more of the specific details, or with other methods, components, devices, steps, and so forth. In other instances, well-known methods, devices, implementations or operations have not been shown or described in detail to avoid obscuring aspects of the invention.

The invention provides a permanent magnet motor voltage self-adaptive control system, as shown in fig. 1 to 3, comprising: the system comprises a control device 4, a three-phase power supply 1, a three-phase transformer 2 and a permanent magnet motor 3;

the first phase of each group of three-phase power supply 1 is connected with a first primary phase tap of a primary coil of a three-phase transformer; the second phase of each group of three-phase power supply is connected with a second primary phase tap of the primary coil of the three-phase transformer; the third phase of each group of three-phase power supply is connected with a third primary phase tap of the primary coil of the three-phase transformer; and a secondary coil of the three-phase transformer is connected with the permanent magnet motor through a relay and a control switch in the control device to control the permanent magnet motor to operate.

Specifically, a primary coil of a three-phase transformer is connected with a three-phase power supply;

each phase of the secondary coil of the three-phase transformer is electrically provided with N gears;

the control device is provided with three-phase power supply circuits the number of which is the same as that of the gears of the secondary coils of the three-phase transformer;

the input end of each phase of electricity in the three-phase power supply line is correspondingly connected with the three-phase electricity of the secondary coil of the three-phase transformer; the output end of each phase of electricity in the three-phase power supply circuit is connected with the permanent magnet motor;

an upper connection switch is respectively arranged in each three-phase power supply circuit; wherein, two three-phase power supply lines are respectively provided with a lower connection switch, and the three-phase power supply line provided with the lower connection switch is a three-phase selection power supply line;

an upper connection switch and a lower connection switch in the three-phase selection power supply line are connected in series; the upper connection switch and the lower connection switch in the same three-phase selective power supply line are not closed at the same time, and the lower connection switch is synchronously closed with the upper connection switch in the non-three-phase selective power supply line according to a control instruction to supply power to the permanent magnet motor.

As a preferred embodiment of the present invention, for example, a mode of controlling the power supply of the permanent magnet motor by using five gears is as follows:

the secondary coil of the three-phase transformer is provided with three groups of secondary taps to form three gears;

the control device is provided with three-phase power supply circuits;

the first three-phase power supply line is provided with a first three-phase control switch KM1 and a fourth three-phase control switch KM 4;

the second three-phase power supply line is provided with a second three-phase control switch KM 2;

the third three-phase power supply line is provided with a third three-phase control switch KM3 and a fifth three-phase control switch KM 5;

the first three-phase control switch KM1, the second three-phase control switch KM2 and the third three-phase control switch KM3 are all upper-connected switches;

the fourth three-phase control switch KM4 and the fifth three-phase control switch KM5 are both connected switches;

according to the control instruction, the second three-phase control switch KM2 or the third three-phase control switch KM3 and the fourth three-phase control switch KM4 respectively form two permanent magnet motor control gears;

the first three-phase control switch KM1 or the second three-phase control switch KM2 and the fifth three-phase control switch KM5 form two permanent magnet motor control gears.

As a preferred embodiment of the present invention, for example, a method for controlling power supply of the permanent magnet motor by using seven gears includes:

the secondary coil of the three-phase transformer is provided with four groups of secondary taps to form four gears;

the control device is provided with four three-phase power supply circuits;

the first three-phase power supply line is provided with a first three-phase control switch KM1 and a fourth three-phase control switch KM 4;

the second three-phase power supply line is provided with a second three-phase control switch KM 2;

the third three-phase power supply line is provided with a third three-phase control switch KM3 and a fifth three-phase control switch KM 5;

a seventh three-phase control switch KM7 is arranged on the fourth three-phase power supply line;

the seventh three-phase control switch KM7, the first three-phase control switch KM1, the second three-phase control switch KM2 and the third three-phase control switch KM3 are upper-connected switches;

the fourth three-phase control switch KM4 and the fifth three-phase control switch KM5 are both connected switches;

according to the control instruction, the seventh three-phase control switch KM7, the second three-phase control switch KM2, or the third three-phase control switch KM3 and the fourth three-phase control switch KM4 form three permanent magnet motor control gears respectively;

the seventh three-phase control switch KM7, or the first three-phase control switch KM1, or the second three-phase control switch KM2 respectively form three permanent magnet motor control gears with the fifth three-phase control switch KM 5.

As a preferred embodiment of the present invention, for example, a mode of controlling power supply of the permanent magnet motor by using three gears is as follows: the secondary coil of the three-phase transformer is provided with two groups of secondary taps to form two gears;

the control device is provided with two three-phase power supply circuits;

the first three-phase power supply line is provided with a first three-phase control switch KM1 and a fourth three-phase control switch KM 4;

the second three-phase power supply line is provided with a third three-phase control switch KM3 and a fifth three-phase control switch KM 5;

the first three-phase control switch KM1 and the third three-phase control switch KM3 are both upper-connected switches;

the fourth three-phase control switch KM4 and the fifth three-phase control switch KM5 are both connected switches;

according to the control instruction, the third three-phase control switch KM3 and the fourth three-phase control switch KM4 form a permanent magnet motor control gear;

the first three-phase control switch KM1 and the fifth three-phase control switch KM5 form a permanent magnet motor control gear.

Of course, the invention can also set more gears, such as nine gears, and more gears to realize the control of the permanent magnet motor according to the actual requirement or the actual use requirement. The specific number of gears is not limited, and the specific connection mode can be deduced based on the connection modes of the third gear, the fifth gear and the seventh gear, or a corresponding mode can be obtained by inference.

Further, the control device may be implemented in various forms. For example, the terminal described in the embodiment of the present invention may include a mobile terminal such as a notebook computer, a PAD, and the like, and a fixed terminal such as a digital TV, a desktop computer, and the like. It will be understood by those skilled in the art that the configuration according to the embodiment of the present invention can be applied to a fixed type terminal in addition to elements particularly used for moving purposes.

The control device may include a wireless communication unit, an audio/video (a/V) input unit, a user input unit, a sensing unit, an output unit, a memory, an interface unit, a controller, and a power supply unit, and the like. It is to be understood that not all illustrated components are required to be implemented. More or fewer components may alternatively be implemented. Elements of the mobile terminal will be described in detail below.

The control means may be implemented in a computer readable medium using, for example, computer software, hardware or any combination thereof. For hardware implementation, the embodiments described herein may be implemented using at least one of an Application Specific Integrated Circuit (ASIC), a Digital Signal Processor (DSP), a Digital Signal Processing Device (DSPD), a Programmable Logic Device (PLD), a Field Programmable Gate Array (FPGA), a processor, a controller, a microcontroller, a microprocessor, and an electronic unit designed to perform the functions described herein, and in some cases, such embodiments may be implemented in a controller. For a software implementation, the implementation such as a process or a function may be implemented with a separate software module that allows performing at least one function or operation. The software codes may be implemented by software applications (or programs) written in any suitable programming language, which may be stored in memory and executed by the controller.

Furthermore, the system of the invention also relates to a manual control mode, and the control device is also provided with a manual three-phase power supply circuit; a manual control switch KM6 is arranged on the manual three-phase power supply line, the first end of the manual three-phase power supply line is connected with a three-phase power supply through a primary coil of a three-phase transformer, and the second end of the manual three-phase power supply line is connected with a permanent magnet motor.

A manually controlled master switch QF may also be provided. A power supply isolation switch Q1 may be provided as a power supply end to control the power supply state of the entire system.

In the drawing, x1, x2, x3, y1, y2, y3, z1, z2, and z3 of the primary side of the three-phase transformer all represent taps, or primary connection terminals. The lower subscript corresponding to a, b, c of the corresponding secondary is also the secondary tap, or secondary connection.

The three-phase control switch can be set according to requirements by adopting a contactor, or a relay, an electric control switch and the like.

The control device related in the system is also provided with a control instruction acquisition module, a control module and a parameter setting module;

the control instruction acquisition module and the parameter setting module are respectively in communication connection with the control module;

the control module acquires system preset parameters through the parameter setting module;

setting a secondary voltage grade E1 of the transformer to be 10-99V; e2 ═ 10-99 volts;

setting a primary voltage gear Ue of the transformer as 300-700V;

setting the startup voltage drop Uf to 10-60 volts;

setting the no-load counter potential E0 to 300-730V;

of course, the specific data can be set based on actual needs, a specific numerical value can be set, a range can be set, and the like.

The control module acquires a control instruction input by a user or a parameter preset by the system through the control instruction acquisition module, and controls the action of the upper link switch and the lower link switch to realize the gear switching of the power supply of the permanent magnet motor.

The control module detects the power supply voltage U in real time; presetting UL as U;

here, U_e-a nominal voltage;

a secondary voltage gear U (V/W)1/U (V/W)2/U (V/W) n of the compensation transformer;

e0 no-load counter potential;

U_fline startup voltage drop;

detecting power supply voltage U, UL becoming U-U before starting up_f(ii) a After the power is turned on, UL is equal to U.

The control module respectively calculates values of ER1, ER2, ER3, ER4 and ER5 according to the following formula;

ER1＝UL (KM6)

according to a control gear command input by a user, selecting the corresponding ER1, or ER2, or ER3, or ER4, or ER5 gear during starting, and starting the permanent magnet motor;

acquiring current gear data in real time in the operation process, and enabling the current gear data to exceed a preset range;

the preset range is that E0-E is less than or equal to E0+ E/2;

executing gear shifting operation and replacing other gear data;

the control module executes gear shifting operation, and whether the value of each current gear ER1, ER2, ER3, ER4 and ER5 is in a preset range or not is acquired through E0-E < (ER1 or ER2 or ER3 or ER4 or ER5) < E0+ E/2; and if a certain gear is in a preset range and the currently selected gear ER is equal to E0, changing the current gear into the gear.

And after the control module determines the gear shifting position and delays for a preset time, executing gear shifting operation and controlling the action of the three-phase control switch corresponding to the gear shifting position.

Based on the system, the invention also provides a permanent magnet motor voltage self-adaptive control method, which comprises the following steps:

closing a power supply and powering on a system;

acquiring a starting control instruction, selecting a corresponding gear during starting according to a gear control instruction input by a user, and controlling the starting permanent magnet motor to operate;

acquiring current gear data in real time in the running process of the permanent magnet motor, comparing the current gear data with a preset range, and judging whether a threshold value is exceeded or not;

if the current gear exceeds the threshold value, executing gear shifting operation, and replacing other gear data;

executing a gear shifting operation, and acquiring whether the value of each current gear ER1, ER2, ER3, ER4 and ER5 is in a preset range or not through E0-E < (ER1 or ER2 or ER3 or ER4 or ER5) < E0+ E/2;

if a certain gear is in a preset range and the currently selected gear ER value is E0, judging whether the manual control switch KM6 is disconnected or not, if the manual control switch KM6 is not disconnected, disconnecting the manual control switch KM6, and after delaying for a preset time, executing a gear shifting operation and controlling the action of the three-phase control switch corresponding to the gear shifting position.

When the gear shifting operation is executed, the lower connection switch is firstly disconnected when the three-phase control switch corresponding to the original gear is disconnected; then the upper connection switch is disconnected;

when the three-phase control switch corresponding to the original gear is closed, the upper-connection switch is closed first, and then the lower-connection switch is closed.

The control method is performed for the fifth gear, and naturally, more gears are performed according to the control method.

In the above formula, for example, when the ER4 gear is selected, the normally open nodes corresponding to KM3 and KM4 are closed.

In the switching process, after the gear to be switched is determined, the normally open switch of the KM6 is immediately switched off, after the preset time length, which can be 20-50 milliseconds, a scheme of switching the target is executed, for example, the gear ER2 is selected, the KM2 is closed, and the KM4 is closed after the preset time length. In the closing process, the KM1, or KM2, or KM3 was closed first, and then the KM4, KM5 were closed.

If ER1 is selected, the KM6 is kept unchanged, and the current gear is kept.

Further, taking the fifth gear as an example, after the system is started, the contactor is controlled to be closed, and the control device is powered on and starts working.

The first step is as follows: detecting power supply voltage U, calculating UL as U-Uf, substituting into five equations

ER1＝UL (KM6)

The second step is that: judging according to the mode, wherein E0-E is less than or equal to E0+ E/2 of the current gear data E;

the third step: and judging that a gear ER1-ER5 is selected, and controlling and starting the permanent magnet motor according to the selected gear.

After starting, acquiring current gear data in real time, and enabling the current gear data to exceed a preset range;

the fourth step: during operation, the power supply voltage U is detected at any time, and the power supply voltage U is substituted into the formula according to the UL ═ U;

the fifth step: calculating the values of ER1, ER2, ER3, ER4 and ER5 at the time;

and a sixth step: when the ER value is equal to E0, or when the current gear position data is compared with a preset range and exceeds a threshold value, the gear is switched. Executing a gear shifting operation, and acquiring whether the value of each current gear ER1, ER2, ER3, ER4 and ER5 is in a preset range or not through E0-E < (ER1 or ER2 or ER3 or ER4 or ER5) < E0+ E/2;

and if the numerical value of a certain gear exceeds the preset range, disconnecting the three-phase control switch corresponding to the original gear, executing gear shifting operation after delaying the preset time length, and controlling the action of the three-phase control switch corresponding to the gear shifting position.

And if the current gear value meets the preset range, the gear shifting is not executed.

If the values of the gears to be shifted are the same, such as the values of ER1, ER2, ER3, ER4 and ER5 to be shifted, the gears to be shifted are preferably set according to preset conditions for shifting.

The seventh step: the detection power supply voltage U which is not stopped in this way is switched to complete the gear switching after the condition is met, and the high-efficiency operation of the equipment is maintained.

Therefore, three groups of voltages can be formed by arranging one group of voltages on the output side of the compensation transformer to adapt to the economic operation of the conventional permanent magnet motor.

Two groups of voltages are arranged on the output side of the compensation transformer, so that five groups of voltages can be formed to adapt to the economic operation of the conventional permanent magnet motor.

Three groups of voltages are arranged on the output side of the compensation transformer, so that seven groups of voltages can be formed to adapt to the economic operation of the conventional permanent magnet motor. By analogy, the finer the voltage, the more the potential of the efficient energy-saving operation of the conventional permanent magnet motor can be excavated, and the control method of the permanent magnet motor is consistent with the control method provided by the invention.

The invention dynamically controls the permanent magnet motor of the existing oil pumping unit in the oil field, and if the operation power factor is lower, the voltage self-adaptive control method and the system of the permanent magnet motor can be applied to dynamically switch the gear operation in real time, thereby ensuring the efficient and economic operation of the permanent magnet motor.

The invention adopts the double-winding compensation transformer, realizes multi-gear voltage by connecting the windings in series, has the obvious advantages of small configuration capacity, small running loss, low manufacturing cost, static voltage regulation of the original ecological transformer, no generation of any harmonic wave and the like, and the control device realizes the running mode of automatic detection and automatic control. The operation process of field operation maintenance personnel is simplified. The control device realizes calculation processing of various input data of the permanent magnet motor, diagnoses the current running state of the permanent magnet motor according to the calculation result, automatically adjusts output voltage, sequentially realizes automatic monitoring, automatic tracking and automatic regulation, provides optimal running voltage for the permanent magnet motor, and ensures that the permanent magnet motor of the oil pumping unit is always in an efficient and economic running state.

The system controls the permanent magnet motor of the existing pumping unit in the oil field, so that the operating power factor of the pumping unit can be always kept above 0.97, and the comprehensive power saving rate can be up to above 20%.