CN106452210B

CN106452210B - Magnetic sensor integrated circuit, motor assembly and application equipment

Info

Publication number: CN106452210B
Application number: CN201610392242.9A
Authority: CN
Inventors: 孙持平; 信飞; 黄建; 杨圣骞; 黄淑娟; 蒋云龙
Original assignee: Dechang Motor (Shenzhen) Co Ltd
Current assignee: Dechang Motor (Shenzhen) Co Ltd
Priority date: 2015-08-07
Filing date: 2016-06-02
Publication date: 2020-11-06
Anticipated expiration: 2036-06-02
Also published as: CN106452210A; MX2016010224A; CN206002675U; BR102016018038A2

Abstract

The embodiment of the invention discloses a magnetic sensor integrated circuit, a motor assembly and application equipment. The magnetic sensor integrated circuit includes a magnetic field detection circuit and an output control circuit. The magnetic field detection circuit is used for detecting a rotor magnetic field of the motor and correspondingly outputting magnetic field detection information. The output control circuit includes a first switch and a second switch. The first switch is connected in the first current path with the output port. A second switch is connected with the output port in a second current path in a direction opposite to the first current path. The first switch and the second switch are selectively conducted under the control of the magnetic field detection information, so that the power supply mode of the motor is controlled. The magnetic sensor integrated circuit provided by the embodiment of the invention expands the functions of the existing magnetic sensor, can reduce the overall circuit cost and improve the circuit reliability.

Description

Magnetic sensor integrated circuit, motor assembly and application equipment

Technical Field

The invention relates to the technical field of magnetic field detection, in particular to a magnetic sensor integrated circuit.

Background

Magnetic sensors are widely used in modern industry and electronic products to sense magnetic field strength to measure physical parameters such as current, position, direction, etc. The motor industry is an important application field of the magnetic sensor, and in the motor, the magnetic sensor can be used as the rotor magnetic pole position sensing.

In the prior art, a magnetic sensor can only output a magnetic field detection result, and a peripheral circuit is additionally arranged to process the magnetic field detection result during specific work, so that the overall circuit is high in cost and poor in reliability.

Disclosure of Invention

In one aspect, embodiments of the present invention provide a magnetic sensor integrated circuit for motor control, including a housing, a semiconductor substrate disposed in the housing, an electronic circuit disposed on the semiconductor substrate, and an input port and an output port extending from the housing. The electronic circuit comprises a magnetic field detection circuit for detecting the rotor magnetic field of the motor and correspondingly outputting magnetic field detection information; and the output control circuit comprises a first switch and a second switch, the first switch and the output port are connected in a first current path, the second switch and the output port are connected in a second current path opposite to the first current path, and the first switch and the second switch are selectively conducted under the control of the magnetic field detection information so as to control the power supply mode of the motor.

Preferably, the output control circuit includes a push-pull output circuit, the first switch and the second switch are complementary semiconductor switches, a current inflow end of the first switch is connected to a higher voltage, a current outflow end of the second switch is connected to a lower voltage, control ends of the first switch and the second switch are respectively connected to an output end of the magnetic field detection circuit, and a common end of the first switch and the second switch is connected to the output port.

Preferably, the magnetic field detection circuit is powered by a first power supply, and the output control circuit is powered by a second power supply different from the first power supply.

Preferably, an average value of the output voltage of the first power supply is smaller than an average value of the output voltage of the second power supply.

Preferably, the input port includes an input port for connecting an external ac power source, and the output control circuit is configured to switch the integrated circuit between at least a first state in which the first current path is made conductive and a second state in which the second current path is made conductive, based on a change in polarity of the ac power source and the magnetic field detection information.

Optionally, the output control circuit is configured to cause the integrated circuit to switch immediately between at least a first state in which the first current path is rendered conductive and a second state in which the second current path is rendered conductive, based on at least the magnetic field detection information.

Optionally, the output control circuit is configured to cause the integrated circuit to switch to the other state after an interval of time elapses between an end of one of a first state in which the first current path is made conductive and a second state in which the second current path is made conductive, based on at least the magnetic field detection information.

Preferably, the output control circuit is configured to cause the output port to pass a load current when the alternating current power source is in a positive half cycle and the rotor magnetic field polarity is a first polarity, or the alternating current power source is in a negative half cycle and the rotor magnetic field polarity is a second polarity opposite to the first polarity, and to cause the output port to pass no load current when the alternating current power source is in the positive half cycle and the rotor magnetic field polarity is the second polarity, or the alternating current power source is in the negative half cycle and the rotor magnetic field polarity is the first polarity.

Optionally, the output control circuit is configured such that current flows for the entire duration of the positive half cycle of the ac power source and the rotor magnetic field polarity is the first polarity, or the negative half cycle of the ac power source and the rotor magnetic field polarity is the second polarity.

Optionally, the output control circuit is configured such that current flows for only a portion of the time period when the ac power source is in the positive half cycle and the rotor magnetic field polarity is in the first polarity, or when the ac power source is in the negative half cycle and the rotor magnetic field polarity is in the second polarity.

Optionally, the magnetic field detection circuit and the output control circuit are powered by the same dc power supply.

Another aspect of the embodiments of the present invention provides a motor assembly, including a motor and a motor driving circuit, where the motor driving circuit has the above-mentioned magnetic sensor integrated circuit.

Preferably, the motor driving circuit further includes a bidirectional conduction switch connected in series with the motor between two ends of an external ac power supply, and the output port of the magnetic sensor integrated circuit is connected to the control end of the bidirectional conduction switch.

Preferably, the motor comprises a stator and a permanent magnet rotor, wherein the stator comprises a stator core and a single-phase winding wound on the stator core.

Preferably, the motor is a single-phase permanent magnet synchronous motor, the rotor comprises at least one permanent magnet, a non-uniform magnetic circuit is formed between the stator and the permanent magnet rotor, the polar axis of the permanent magnet rotor is offset by an angle relative to the central axis of the stator when the permanent magnet rotor is at rest, and the rotor runs at a constant speed of 60f/p circles/minute in a steady state stage after the stator winding is electrified, wherein f is the frequency of the alternating current power supply, and p is the number of pole pairs of the rotor.

Preferably, the motor assembly further includes a step-down transformer for stepping down the ac power and supplying the stepped-down ac power to the magnetic sensor integrated circuit.

Preferably, the output control circuit of the magnetic sensor integrated circuit is configured to turn on the bidirectional conduction switch when the alternating current power supply is in a positive half cycle and the magnetic field of the rotor is of a first polarity, or the alternating current power supply is in a negative half cycle and the magnetic field of the rotor is of a second polarity opposite to the first polarity, and to turn off the bidirectional conduction switch when the alternating current power supply is in a negative half cycle and the rotor is of the first polarity, or the alternating current power supply is in a positive half cycle and the rotor is of the second polarity.

Preferably, the output control circuit is configured to control current to flow from the output port to the bidirectional conducting switch when the signal output by the ac power source is in a positive half-cycle and the magnetic field of the rotor is of a first polarity, and to control current to flow from the bidirectional conducting switch to the output port when the signal output by the ac power source is in a negative half-cycle and the magnetic field of the rotor is of a second polarity.

It is a further aspect of an embodiment of the present invention to provide an apparatus having the above-described motor assembly.

Preferably, the application device comprises a pump, a fan, a household appliance or a vehicle.

The magnetic sensor integrated circuit provided by the embodiment of the invention expands the functions of the existing magnetic sensor, can reduce the overall circuit cost and improve the circuit reliability.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

FIG. 1 is a schematic diagram of a magnetic sensor integrated circuit according to an embodiment of the present invention;

FIG. 2 is a schematic diagram of a magnetic sensor integrated circuit according to another embodiment of the present invention;

FIG. 3 is a diagram illustrating an output control circuit of a magnetic sensor integrated circuit according to an embodiment of the present invention;

FIG. 3A is a circuit diagram of an embodiment of the output control circuit of FIG. 3;

FIG. 4 is a diagram illustrating an output control circuit of a magnetic sensor integrated circuit according to another embodiment of the present invention;

FIG. 5 is a schematic diagram of a magnetic sensor integrated circuit according to yet another embodiment of the present invention;

FIG. 6 is a schematic diagram of a magnetic sensor integrated circuit according to yet another embodiment of the present invention;

FIG. 7 is a schematic diagram of a rectifying circuit of a magnetic sensor integrated circuit according to an embodiment of the present invention;

FIG. 8 is a diagram illustrating a magnetic field detection circuit of a magnetic sensor integrated circuit according to an embodiment of the present invention;

FIG. 9 is a circuit block diagram of an electromechanical machine component provided in accordance with one embodiment of the present invention;

fig. 10 is a schematic structural diagram of a motor in the motor assembly according to an embodiment of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention, but the present invention may be practiced in other ways than those specifically described and will be readily apparent to those of ordinary skill in the art without departing from the spirit of the present invention, and therefore the present invention is not limited to the specific embodiments disclosed below.

The magnetic sensor integrated circuit provided by the embodiment of the present invention will be described below by taking the application of the magnetic sensor integrated circuit to a motor as an example.

Referring to fig. 1, an embodiment of the present invention provides a magnetic sensor integrated circuit including a case 2, a semiconductor substrate (not shown) provided in the case, electronic circuits provided on the semiconductor substrate, and input ports a1, a2, and an output port Pout extending from the case. The electronic circuit includes:

a magnetic field detection circuit 20 for detecting a rotor magnetic field of the motor and outputting magnetic field detection information accordingly; and

and an output control circuit 30 including a first switch and a second switch, wherein the first switch and the output port are connected in a first current path, the second switch and the output port are connected in a second current path opposite to the first current path, and the first switch and the second switch are selectively turned on under the control of the magnetic field detection information, so as to control a power supply mode of the motor. In the embodiment of the present invention, the first current path and the second current path are not limited to have completely identical paths, and may have different paths as long as the directions of the currents flowing through the output ports are opposite.

In one embodiment of the present invention, and with reference to FIG. 2, the magnetic field detection circuit 20 is powered by a first power source 40 and the output control circuit 30 is powered by a second power source 50 that is different from the first power source 40. Preferably, the first power source 40 may be a constant-amplitude dc power source, and the second power source 50 may be a variable-amplitude dc power source or a constant-amplitude dc power source. The average value of the output voltage of the first power supply 40 is smaller than the average value of the output voltage of the second power supply 50. The power consumption of the integrated circuit can be reduced by supplying power to the magnetic field detection circuit 20 with a smaller power supply, and the power supply to the output control circuit 30 with a larger power supply can enable the output port to provide higher load current, so as to ensure that the integrated circuit has sufficient driving capability. It will be appreciated that in other embodiments, the magnetic field detection circuit 20 and the output control circuit 40 may also be powered by the same dc power source.

In one embodiment of the present invention, referring to fig. 3, the output control circuit includes a push-pull output circuit, and the first switch 31 and the second switch 32 are a pair of complementary semiconductor switches. The current input end of the first switch 31 is connected with a higher voltage, the current output end of the second switch 32 is connected with a lower voltage, the control ends of the first switch 31 and the second switch 32 are respectively connected with the output end of the magnetic field detection circuit, and the common end of the first switch 31 and the second switch 32 is connected with the output port Pout.

In one embodiment, as shown in fig. 3A, the first switch 31 and the second switch 32 are a pair of complementary Metal Oxide Semiconductor Field Effect Transistors (MOSFETs). The first switch 31 is a P-type MOSFET that is turned on at a low level, the second switch 32 is an N-type MOSFET that is turned on at a high level, wherein the first switch 31 and the output port Pout are connected in a first current path, the second switch 32 and the output port Pout are connected in a second current path, control terminals of both the first switch 31 and the second switch 32 are connected to the magnetic field detection circuit 20, a current input terminal of the first switch 31 is connected to a higher voltage (e.g., a second power supply), a current output terminal is connected to a current input terminal of the second switch 32, and a current output terminal of the second switch 32 is connected to a lower voltage (e.g., ground). If the magnetic field detection information output by the magnetic field detection circuit 20 is at a low level, the first switch 31 is turned on, the second switch 32 is turned off, and the load current flows out from a higher voltage through the first switch 31 and the output port Pout, and if the magnetic field detection information output by the magnetic field detection circuit 20 is at a high level, the second switch 32 is turned on, the first switch 31 is turned off, and the load current flows into the output port Pout from the outside and flows through the second switch 32.

It is understood that in other embodiments, the first switch and the second switch may be other types of semiconductor switches, for example, Junction Field Effect Transistors (JFETs) or other field effect transistors such as metal semiconductor field effect transistors (MESFETs).

Referring to fig. 4, in another embodiment of the present invention, the first switch 31 is a high-level conducting switch tube, the second switch 32 is a unidirectional conducting diode, and the control terminal of the first switch 31 and the cathode of the second switch 32 are connected to the magnetic field detection circuit 20. A current input terminal of the first switch 31 is connected to the second power supply 50, and a current output terminal of the first switch 31 and an anode of the second switch 32 are both connected to the output port Pout. The first switch 31 and the output port Pout are connected in a first current path, the output port Pout, the second switch 32 and the magnetic field detection circuit 20 are connected in a second current path, if the magnetic field detection information output by the magnetic field detection circuit 20 is at a high level, the first switch 31 is turned on, the second switch 32 is turned off, the load current flows out from the second power supply 50 through the first switch 31 and the output port Pout, if the magnetic field detection information output by the magnetic field detection circuit 20 is at a low level, the second switch 32 is turned on, the first switch 31 is turned off, and the load current flows into the output port Pout from the outside and flows through the second switch 32. It is understood that, in other embodiments of the present invention, the first switch 31 and the second switch 32 may have other structures, and the present invention is not limited thereto, as the case may be.

In one embodiment of the present invention, the input port includes an input port for connecting an external ac power source, and the output control circuit 30 is configured to switch the integrated circuit between at least a first state in which the first current path is made conductive and a second state in which the second current path is made conductive, based on a change in polarity of the ac power source and the magnetic field detection information.

It should be noted that, in the embodiment of the present invention, the magnetic sensor integrated circuit switches between the first state and the second state, and is not limited to the case where the magnetic sensor integrated circuit switches to the other state immediately after one state is ended, but also includes the case where the magnetic sensor integrated circuit switches to the other state after a certain time interval after one state is ended. In a preferred embodiment, the output port of the magnetic sensor integrated circuit has no output during the interval between two state switches.

Further, the output control circuit 30 is configured to cause the output port to flow a load current when the alternating current power source is in a positive half cycle and the magnetic field detection circuit 20 detects that the polarity of the rotor magnetic field is a first polarity, or when the alternating current power source is in a negative half cycle and the magnetic field detection circuit 20 detects that the polarity of the rotor magnetic field is a second polarity opposite to the first polarity, and to cause the output port to flow no load current when the alternating current power source is in the positive half cycle and the polarity of the rotor magnetic field is the second polarity, or when the alternating current power source is in the negative half cycle and the polarity of the rotor magnetic field is the first polarity. It should be noted that when the ac power source is in the positive half cycle and the external magnetic field is in the first polarity, or the ac power source is in the negative half cycle and the external magnetic field is in the second polarity, the load current flowing through the output port includes both the case where the load current flows through the output port during the entire duration of the two cases, and the case where the load current flows through the output port during only a part of the time period in the two cases.

In one embodiment of the present invention, the input port may include a first input port and a second input port to which an external ac power source is connected. The integrated circuit further includes a rectifier circuit 60 for converting the alternating current output from the external alternating current power supply 70 into a direct current power supply. In the present invention, the connection of the input port to the external power source includes a case where the input port is directly connected to both ends of the external power source, and also includes a case where the input port and the external load are connected in series to both ends of the external power source.

Preferably, referring to fig. 5, the integrated circuit further includes a voltage regulating circuit 80 located between the rectifying circuit 60 and the magnetic field detecting circuit 20, in this embodiment, the rectifying circuit 60 can be used as the second power source 50, and the voltage regulating circuit 80 can be used as the first power source 40. The voltage adjusting circuit 80 is used for adjusting the dc power output by the rectifying circuit 60 to a lower dc power. The output control circuit 30 may be powered by the output voltage of the rectifying circuit 60, and the magnetic field detection circuit 20 may be powered by the output voltage of the voltage adjusting circuit 80.

In one embodiment of the present invention, referring to fig. 6, the rectifying circuit 60 includes: the full-wave rectifier circuit comprises a full-wave rectifier bridge 61 and a voltage stabilizing unit 62, wherein the full-wave rectifier bridge 61 is used for converting alternating current output by the alternating current power supply 70 into direct current, and the voltage stabilizing unit 62 is used for stabilizing the direct current output by the full-wave rectifier bridge 61 within a preset value range.

Fig. 7 shows a specific circuit of the rectifying circuit 60, wherein the voltage stabilizing unit 62 includes a zener diode 621 connected between two output terminals of the full-wave rectifying bridge 61, and the full-wave rectifying bridge 61 includes: a first diode 611 and a second diode 612 connected in series and a third diode 613 and a fourth diode 614 connected in series; a common terminal of the first diode 611 and the second diode 612 is electrically connected to the first input port VAC +; a common terminal of the third diode 613 and the fourth diode 614 is electrically connected to the second input port VAC-;

an input end of the first diode 611 is electrically connected to an input end of the third diode 613 to form a ground output end of the full-wave rectifier bridge, an output end of the second diode 612 is electrically connected to an output end of the fourth diode 614 to form a voltage output end VDD of the full-wave rectifier bridge, and the zener diode 621 is connected between a common end of the second diode 612 and the fourth diode 614 and a common end of the first diode 611 and the third diode 613. In the embodiment of the present invention, the power supply terminal of the output control circuit 30 may be electrically connected to the voltage output terminal of the full-wave rectifier bridge 61.

In one embodiment of the present invention, as shown in fig. 8, the magnetic field detection circuit 20 includes: a magnetic field detection element 21 for detecting an external magnetic field and converting it into an electric signal; a signal processing unit 22 for amplifying and de-interfering the electrical signal; and an analog-to-digital conversion unit 23, configured to convert the amplified and interference-removed electrical signal into the magnetic field detection information, where for an application that only needs to identify the magnetic field polarity of the external magnetic field, the magnetic field detection information may be a switch-type digital signal. The magnetic field detection element 21 may preferably be a hall plate.

The magnetic sensor integrated circuit provided by the embodiment of the invention is described below with reference to a specific application.

As shown in fig. 9, an embodiment of the present invention further provides a motor assembly, including: the magnetic sensor integrated circuit comprises a motor 200 powered by an alternating current power supply 100, a bidirectional conduction switch 300 connected in series with the motor 200, and a magnetic sensor integrated circuit 400 provided according to any one of the above embodiments of the invention. The output port of the magnetic sensor integrated circuit 400 is electrically connected to the control terminal of the bidirectional conducting switch 300. Preferably, the bidirectional conducting switch 300 may be a TRIAC (TRIAC). It will be appreciated that the bidirectional conducting switch may also be implemented by other types of suitable switches, for example, two silicon controlled rectifiers connected in anti-parallel may be provided, and a corresponding control circuit is provided, via which the two silicon controlled rectifiers are controlled in a predetermined manner in dependence on the output signal of the output port of the magnetic sensor integrated circuit.

Preferably, the motor assembly further includes a voltage dropping circuit 500 for dropping the ac power 100 and providing the dropped ac power to the magnetic sensor integrated circuit 400. Magnetic sensor integrated circuit 400 is mounted proximate to the rotor of motor 200 to sense changes in the magnetic field of the rotor.

In one embodiment of the present invention, the motor is a synchronous motor, and it is understood that the magnetic sensor integrated circuit of the present invention is not only applicable to synchronous motors, but also to other types of permanent magnet motors such as dc brushless motors. As shown in fig. 10, the synchronous machine includes a stator and a rotor 11 rotatable relative to the stator. The stator includes a stator core 12 and a stator winding 16 wound around the stator core 12. The stator core 12 may be made of soft magnetic material such as pure iron, cast steel, electrical steel, silicon steel, and the like. The rotor 11 has permanent magnets and the rotor 11 operates at a constant speed in the steady state phase at 60f/p turns/min with the stator winding 16 in series with the ac power supply, where f is the frequency of the ac power supply and p is the number of pole pairs of the rotor. In the present embodiment, the stator core 12 has two opposing pole portions 14. Each pole portion has a pole arc face 15, and the outer surface of the rotor 11 is opposed to the pole arc face 15 with a substantially uniform air gap formed therebetween. The term substantially uniform air gap as used herein means that a majority of the air gap between the stator and the rotor is uniform and only a minority of the air gap is non-uniform. Preferably, the pole arc surface 15 of the stator pole part is provided with a concave starting groove 17, and the part of the pole arc surface 15 except the starting groove 17 is concentric with the rotor. The above arrangement creates an uneven magnetic field, ensuring that the pole axis S1 of the rotor is inclined at an angle relative to the central axis S2 of the stator pole section when the rotor is at rest, allowing the rotor to have a starting torque each time the motor is energized by the integrated circuit. Wherein the rotor pole axis S1 refers to the dividing line between two poles of different polarity of the rotor, and the central axis S2 of the stator pole section 14 refers to the connecting line passing through the centers of the two stator pole sections 14. In this embodiment, the stator and the rotor each have two magnetic poles. It will be appreciated that in further embodiments the number of poles of the stator and rotor may be unequal, with further poles, for example four, six, etc.

In a preferred embodiment, the bidirectional switch 300 is a TRIAC (TRIAC), the rectifying circuit 60 is the circuit shown in fig. 7, the output control circuit is the circuit shown in fig. 3, the current input terminal of the first switch 31 of the output control circuit 30 is connected to the voltage output terminal of the full-wave rectifying bridge 61, and the current output terminal of the second switch 32 is connected to the ground output terminal of the full-wave rectifying bridge 61. When the signal output by the ac power supply 100 is in the positive half cycle and the magnetic field detection circuit 20 outputs the low level, the first switch 31 of the output control circuit 30 is turned on and the second switch 32 is turned off, so that the current flows through the ac power supply 100, the motor 200, the first input terminal of the integrated circuit 400, the step-down circuit (not shown), the output terminal of the second diode 612 of the full-wave rectifier bridge 61, the first switch 31 of the output control circuit 30, flows from the output port to the bidirectional switch 300, and returns to the ac power supply 100. When the TRIAC300 is turned on, the series branch formed by the voltage step-down circuit 500 and the magnetic sensor integrated circuit 400 is short-circuited, the magnetic sensor integrated circuit 400 stops outputting due to no power supply voltage, and the TRIAC300 remains on in the absence of a driving current between the control electrode and the first anode thereof because the current flowing between the two anodes of the TRIAC300 is sufficiently large (higher than the holding current thereof). When the signal output by the ac power supply 100 is in the negative half cycle and the magnetic field detection circuit 20 outputs the high level, the first switch 31 in the output control circuit 30 is turned off and the second switch 32 is turned on, and the current flows out from the ac power supply 100, flows into the output port from the bidirectional conduction switch 300, and returns to the ac power supply 100 through the second switch 32 of the output control circuit 30, the ground output terminal of the full-wave rectifier bridge 61, the first diode 611, the first input terminal of the integrated circuit 400, and the motor 200. Similarly, when the TRIAC300 is turned on, the magnetic sensor integrated circuit 400 is short-circuited to stop outputting the short circuit, and the TRIAC300 may be kept on. When the signal output by the ac power source 100 is in the positive half period and the magnetic field detection circuit 20 outputs the high level, or the signal output by the ac power source 100 is in the negative half period and the magnetic field detection circuit 20 outputs the low level, neither the first switch 31 nor the second switch 32 of the output control circuit 30 can be turned on, and the TRIAC300 is turned off. Therefore, the output control circuit 30 can make the integrated circuit control the bidirectional switch 300 to switch between the on state and the off state in a predetermined manner based on the polarity change of the ac power supply 100 and the magnetic field detection information, and further control the energization manner of the stator winding 16, so that the changed magnetic field generated by the stator matches with the magnetic field position of the rotor to drag the rotor to rotate only in a single direction, thereby ensuring that the rotor has a fixed rotation direction each time the motor is energized.

In the motor assembly according to another embodiment of the present invention, the motor may be connected in series with the bidirectional conduction switch between two ends of the external ac power source, and a first series branch formed by connecting the motor in series with the bidirectional conduction switch may be connected in parallel with a second series branch formed by the voltage step-down circuit and the magnetic sensor integrated circuit. The output port of the magnetic sensor integrated circuit is connected with the bidirectional conduction switch, and the bidirectional conduction switch is controlled to be switched between a conduction state and a cut-off state in a preset mode, so that the conduction mode of the stator winding is controlled.

The motor assembly of the embodiment of the present invention can be used in, but not limited to, a pump, a fan, a household appliance, such as a washing machine, a dishwasher, a range hood, an exhaust fan, etc., a vehicle , etc.

It should be noted that, although the embodiment of the invention is described by taking the integrated circuit as an example for being applied to a motor, the application field of the integrated circuit provided by the embodiment of the invention is not limited to this.

In the description, each part is described in a progressive manner, each part is emphasized to be different from other parts, and the same and similar parts among the parts are referred to each other.

It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.

The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A magnetic sensor integrated circuit for motor control comprises a shell, a semiconductor substrate arranged in the shell, an electronic circuit arranged on the semiconductor substrate, and an input port and an output port which extend out of the shell; the input port is used for connecting an external power supply, the output port is connected with a control end of a switch for controlling the power supply mode of the motor, and the electronic circuit comprises:

the magnetic field detection circuit is used for detecting a rotor magnetic field of the motor and correspondingly outputting magnetic field detection information, and the magnetic field detection information is a switch type digital signal; and

an output control circuit including a first switch connected with the output port in a first current path and a second switch connected with the output port in a second current path in a direction opposite to the first current path, the first current path flowing from a higher voltage to the output port via the first switch when the first switch is controlled to be turned on by the switch-type digital signal; when the second switch is controlled to be conducted by the switch type digital signal, the second current path flows to a lower voltage from the output port which is opposite to the first current path; the first switch and the second switch are selectively conducted under the control of the magnetic field detection information, so that the power supply mode of the motor is controlled.

2. The magnetic sensor integrated circuit of claim 1, wherein the output control circuit comprises a push-pull output circuit, the first switch and the second switch are a pair of complementary semiconductor switches, a current inflow terminal of the first switch is connected to the higher voltage, a current outflow terminal of the second switch is connected to the lower voltage, control terminals of the first switch and the second switch are each connected to an output terminal of the magnetic field detection circuit, and a common terminal of the first switch and the second switch is connected to the output port.

3. The magnetic sensor integrated circuit of claim 1, wherein the magnetic field sensing circuit is powered by a first power supply and the output control circuit is powered by a second power supply different from the first power supply.

4. The magnetic sensor integrated circuit according to claim 3, wherein an average value of the output voltage of the first power supply is smaller than an average value of the output voltage of the second power supply.

5. The magnetic sensor integrated circuit according to claim 1, wherein the input port comprises an input port for connecting an external ac power supply, and the output control circuit is configured to switch the integrated circuit between at least a first state in which the first current path is made conductive and a second state in which the second current path is made conductive, based on a change in polarity of the ac power supply and the magnetic field detection information.

6. The magnetic sensor integrated circuit of claim 1, wherein the output control circuit is configured to cause the integrated circuit to switch immediately between at least a first state in which the first current path is rendered conductive and a second state in which the second current path is rendered conductive based on at least the magnetic field detection information.

7. The magnetic sensor integrated circuit of claim 1, wherein the output control circuit is configured to cause the integrated circuit to switch to the other state after an interval of time elapses after one of a first state in which the first current path is made conductive and a second state in which the second current path is made conductive ends, based at least on the magnetic field detection information.

8. The magnetic sensor integrated circuit of claim 1, wherein the output control circuit is configured to cause the output port to pass a load current when the motor is connected to an ac power source with a positive half cycle and the rotor magnetic field polarity is a first polarity, or the ac power source with a negative half cycle and the rotor magnetic field polarity is a second polarity opposite the first polarity, and to cause the output port to pass no load current when the ac power source with a positive half cycle and the rotor magnetic field polarity is the second polarity, or the ac power source with a negative half cycle and the rotor magnetic field polarity is the first polarity.

9. The magnetic sensor integrated circuit of claim 8, wherein the output control circuit is configured to flow current for the entire duration of the positive half-cycle of the ac power source and the rotor magnetic field polarity is a first polarity, or the negative half-cycle of the ac power source and the rotor magnetic field polarity is a second polarity.

10. The magnetic sensor integrated circuit of claim 8, wherein the output control circuit is configured such that current flows only for a portion of the time when the alternating current power source is in a positive half cycle and the rotor magnetic field polarity is in a first polarity, or when the alternating current power source is in a negative half cycle and the rotor magnetic field polarity is in a second polarity.

11. The magnetic sensor integrated circuit of claim 1, wherein the magnetic field detection circuit and the output control circuit are powered by the same dc power supply.

12. A motor assembly comprising a motor and a motor drive circuit having a magnetic sensor integrated circuit as claimed in any one of claims 1 to 11.

13. The motor assembly of claim 12 wherein said motor drive circuit further comprises a bidirectional conduction switch connected in series with said motor between the terminals of an external ac power source; and the output port of the magnetic sensor integrated circuit is connected with the control end of the bidirectional conduction switch.

14. The motor assembly of claim 13, wherein the motor comprises a stator and a permanent magnet rotor, the stator comprising a stator core and a single phase winding wound around the stator core.

15. An electric motor assembly as claimed in claim 14, wherein the electric motor is a single-phase permanent magnet synchronous motor, the rotor comprises at least one permanent magnet, the stator has a stator pole portion, the pole arc surface of the stator pole portion is provided with an inwardly concave starting slot, the part of the pole arc surface except the starting slot is concentric with the rotor, an uneven magnetic circuit is formed between the stator and the permanent magnet rotor, the pole axis of the permanent magnet rotor is offset by an angle relative to the central axis of the stator when the permanent magnet rotor is at rest, and the rotor operates at a constant speed of 60f/p turns/min in a steady state stage after the single-phase winding is energized, wherein f is the frequency of the alternating current power supply, and p is the number of pole pairs of the rotor.

16. The motor assembly of claim 13, further comprising a step-down converter for stepping down the ac power to the magnetic sensor integrated circuit.

17. The electric motor assembly of claim 13, wherein the output control circuit of the magnetic sensor integrated circuit is configured to turn the bidirectional conduction switch on when the ac power source is in a positive half-cycle and the magnetic field of the rotor is of a first polarity, or the ac power source is in a negative half-cycle and the magnetic field of the rotor is of a second polarity opposite the first polarity, and to turn the bidirectional conduction switch off when the ac power source is in a negative half-cycle and the rotor is of the first polarity, or the ac power source is in a positive half-cycle and the rotor is of the second polarity.

18. The electric motor assembly of claim 17, wherein the output control circuit is configured to control current flow from the output port to the bidirectional conductive switch when the signal from the ac power source is in a positive half-cycle and the magnetic field of the rotor is of a first polarity, and to control current flow from the bidirectional conductive switch to the output port when the signal from the ac power source is in a negative half-cycle and the magnetic field of the rotor is of a second polarity.

19. A use device having an electric machine assembly according to any one of claims 12 to 18.

20. The application device according to claim 19, characterized in that the application device comprises a pump, a fan, a household appliance or a vehicle.