Driving system, circuit board with first circuit and heating and ventilation equipment

Abstract

The invention relates to a driving system, a circuit board with a first circuit and heating and ventilation equipment, and belongs to the technical field of electronics. The driving system comprises two first circuits and a driving circuit. Each first circuit is used for electrically connecting two lead terminals of one stator coil in the stepping motor, and the first circuit comprises a sub-module circuit; and the driving circuit is used for driving the two first circuits to control the stepping motor. The first circuit comprising the sub-module circuit is adopted to control the stepping motor, the current mainstream four-path Darlington circuit is replaced to control the two-phase five-wire unipolar stepping motor, the sub-module circuit has the core characteristic of improving the current amplification capability, and is provided with a high-current gain circuit, and the sub-module circuit is provided with a high-current gain circuit. And meanwhile, the saturation voltage drop problem of a traditional Darlington circuit is reduced, and compared with a conventional Darlington tube, the conduction loss of the sub-module circuit is low, so that the power consumption of a driving system can be reduced, and the power consumption of the whole heating and ventilation equipment is further reduced.

Description

Technical Field

[0001] The present application belongs to the field of electronic circuit technology, and specifically relates to a drive system, a circuit board with a first circuit, and HVAC equipment. Background Art

[0002] Electronic devices driven by servo motors, such as electronic valves, are widely used in HVAC equipment like air conditioners. Stepper motors, due to their simple structure and low cost, are currently used to drive and control the opening and closing servos of many electronic valves. Currently, traditional Darlington circuits are used to control two-phase, five-wire, unipolar stepper motors, amplifying the input current to the stepper motor. Traditional Darlington circuits, which consist of at least two transistors, suffer from high losses, making them less energy-efficient. Summary of the Invention

[0003] In view of this, the purpose of this application is to provide a drive system, a circuit board with a first circuit, and HVAC equipment to improve the problem that the current drive system has high power consumption and is not conducive to energy saving.

[0004] The embodiment of the present application is implemented as follows: In a first aspect, an embodiment of the present application provides a drive system, comprising: two first circuits and a drive circuit; each first circuit is used to electrically connect two lead terminals of a stator coil in a stepper motor (short for a two-phase four-wire bipolar stepper motor), and each first circuit includes a sub-module circuit; the drive circuit is used to drive the two first circuits to control the stepper motor; the sub-module circuit includes: a current limiting component, a first transistor and a second transistor; the collector of the first transistor and the collector of the second transistor are not interconnected, and the collector of the first transistor is electrically connected to the power supply of the stepper motor through the current limiting component, and the collector of the second transistor is used to electrically connect to the stator coil.

[0005] In the above-described embodiment, the present application utilizes a first circuit comprising a sub-module circuit to control a stepper motor, replacing the currently mainstream four-way Darlington circuit for controlling two-phase, five-wire, unipolar stepper motors. This reduces the power consumption of the drive system and, consequently, the power consumption of the entire HVAC equipment. The core feature of the sub-module circuit is its improved current amplification capability while reducing the saturation voltage drop problem of traditional Darlington circuits. Compared to conventional Darlington transistors, the sub-module circuit in the present application exhibits lower conduction losses. Specifically, the collectors of the first and second transistors in the sub-module circuit are not interconnected (conventional Darlington circuits also include first and second transistors, and the interconnected collectors of the first and second transistors result in a high saturation voltage drop for the second transistor). Instead, they are directly connected to the stepper motor's power supply via a current-limiting component. In this way, when the first transistor is turned on, the power supply can provide sufficient base current to the second transistor through the first transistor, and is not limited by the collector of the second transistor, so that the second transistor can be fully saturated and the saturation voltage drop of the second transistor can be reduced, thereby reducing the conduction loss of the second transistor, thereby greatly reducing the heat generated by the circuit, thereby reducing the power consumption of the drive system, and then reducing the power consumption of the entire HVAC equipment.

[0006] In a second aspect, an embodiment of the present application further provides a circuit board having a first circuit, comprising: a first half-bridge and a second half-bridge; the input end of the first half-bridge is used to electrically connect to a drive circuit, and the output end of the first half-bridge is used to electrically connect to a lead terminal of a stator coil in a stepper motor, the first half-bridge comprises an upper bridge arm and a lower bridge arm, the lower bridge arm of the first half-bridge comprises a sub-module circuit, and the upper bridge arm of the first half-bridge comprises a switching transistor; the input end of the second half-bridge is used to electrically connect to the drive circuit, and the output end of the second half-bridge is used to electrically connect to another lead terminal of a stator coil in the stepper motor, the second half-bridge comprises an upper bridge arm and a lower bridge arm, the lower bridge arm of the second half-bridge comprises a sub-module circuit, and the upper bridge arm of the second half-bridge comprises a switching transistor; the sub-module circuit comprises: a current limiting component, a first transistor and a second transistor; the collector of the first transistor and the collector of the second transistor are not interconnected, and the collector of the first transistor is connected to the power supply of the stepper motor through the current limiting component, and the collector of the second transistor is used to electrically connect to the stator coil.

[0007] In the above-described embodiment, by improving the lower bridge arm of the first circuit, a first circuit comprising a submodule circuit is employed to control a stepper motor, replacing the traditional Darlington circuit used to control a two-phase, five-wire, unipolar stepper motor. This reduces the power consumption of the drive system, and thus the entire HVAC equipment. The core feature of the submodule circuit is its improved current amplification capability while reducing the saturation voltage drop problem of the traditional Darlington circuit. Compared to conventional Darlington transistors, the submodule circuit has lower conduction losses, significantly reducing circuit heat generation, thereby reducing the power consumption of the drive system and, consequently, the entire HVAC equipment.

[0008] On the third aspect, an embodiment of the present application also provides a HVAC equipment, including a first drive system and a flow driving mechanism, the first drive system is connected to the stepper motor in the flow driving mechanism, and the flow driving mechanism is used to drive the flow of the medium in the HVAC equipment; the first drive system includes a drive circuit and two first circuits; each first circuit is used to electrically connect two lead terminals of a stator coil in the stepper motor, and each first circuit includes a sub-module circuit; the drive circuit is used to drive the two first circuits to control the stepper motor; the sub-module circuit includes: a current limiting component, a first transistor and a second transistor; the collector of the first transistor and the collector of the second transistor are not interconnected, and the collector of the first transistor is connected to the power supply of the stepper motor through the current limiting component, and the collector of the second transistor is used to connect the stator coil.

[0009] In the above-described embodiment, this application utilizes a first circuit comprising a submodule circuit to control a stepper motor to drive the flow of media within the HVAC equipment. Due to the core characteristics of the submodule circuit, it improves current amplification capability while reducing the saturation voltage drop of traditional Darlington circuits. The submodule circuit has low conduction losses, significantly reducing circuit heat generation and, consequently, lowering the power consumption of the entire HVAC equipment. Therefore, this application offers the advantages of energy conservation and low cost.

[0010] Other features and advantages of the present application will be described in the following description. The purpose and other advantages of the present application can be realized and obtained through the structures specifically pointed out in the written description and the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] The following is a brief introduction to the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings.

[0012] Figure 1 A schematic diagram of the circuit principle of a drive system driving a tapped stepping motor in the prior art; Figure 2 It is a circuit diagram of a Darlington transistor in the prior art; Figure 3 A connection diagram of a driving system is shown; Figure 4 A circuit schematic diagram of a first circuit is shown; Figure 5 A connection diagram of a driving circuit connected with the first circuit is shown; Figure 6 A circuit schematic diagram of a pre-circuit connected with the first circuit is shown; Figure 7 A circuit schematic diagram of a pre-circuit with common protection connected with the first circuit is shown; Figure 8 A circuit schematic diagram of a first half-bridge pre-circuit with common protection connected with a first half-bridge in the first circuit is shown; Figure 9 A connection diagram of a control circuit connected with the first driving circuit is shown. DETAILED DESCRIPTION

[0013] The embodiments of the present application will be described below in conjunction with the drawings. Obviously, the described embodiments are only part of, but not all of the embodiments of the present application. The following embodiments can be used as examples to illustrate the technical solutions of the present application, but cannot be used to limit the protection scope of the present application. Those skilled in the art can understand that the following embodiments and the features in the embodiments can be combined with each other without conflict.

[0014] It should be noted that: similar labels and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in the subsequent drawings. At the same time, in the description of the present application, the relationship terms such as "first", "second" and the like are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between the entities or operations. Moreover, the terms "include", "contain" or any other variants thereof are intended to cover non-exclusive inclusion, so that the process, article or device including a series of elements not only includes those elements, but also includes other elements not explicitly listed, or includes elements inherent to such process, article or device.

[0015] Furthermore, the term "and / or" in the present application is only a description of the association relationship of the associated objects, which means that there can be three relationships, for example, A and / or B, which can represent the three cases of A alone, A and B together, and B alone.

[0016] In the description of the embodiments of the present application, unless otherwise clearly specified or limited, the technical term "connection" may refer to a direct connection or an indirect connection through an intermediate medium.

[0017] The inventors of this application have found that the conduction loss of the drive system of the stepper motor in the current electronic valve (such as the air conditioning valve) is large, which is not conducive to energy saving. Figure 1 As shown, the driver IC1 in the current drive system mainly adopts the traditional Darlington tube control. The traditional Darlington tube is marked as four phases A, B, C, and D respectively. The controller such as the Micro Controller Unit (MCU) outputs a four-phase eight-beat timing signal to turn on the four paths of the Darlington tube in turn, that is, from A→AB→B→BC→C→CD→D→DA→A. One cycle has a total of 8 steps. The timing beat of A→AB→B→BC→C→CD→D→DA→A can be defined as forward step rotation, and the timing beat of A→AD→D→DC→C→CB→B→BA→A can be defined as reverse step rotation. Figure 1 The SM (Stepper Motor) in the figure is a two-phase five-wire tapped unipolar stepper motor, referred to as a "tapped five-wire" stepper motor. The "tapped five-wire" stepper motor is connected to the driver IC1 through five wire harnesses (common end, A phase, B phase, C phase, and D phase). Figure 1 The driver IC1 in the figure is a common Darlington driver IC, such as ULN2003.

[0018] Among them, the Darlington tube is composed of two BJT (Bipolar Junction Transistor, also known as triode) tubes, and its schematic diagram is as follows Figure 2 As shown, the emitter e of the first transistor Q3 is connected to the base b of the second transistor Q4. If the current flowing into Q3's base is Ib3, then Q3's emitter current Ie3 = Q4's base current Ib4 = Ib3*(1+β3), and Ic4 = Ib4*β4 = Ib3*(1+β3)*β4. In other words, the collector c of the Darlington transistor can obtain a current of Ic3 + Ic4, where β3 is the current amplification factor of Q3 and β4 is the current amplification factor of Q4. Although Q3 can be fully saturated and the saturation voltage drop can be as low as 0.2V, Q4's Vbe (base-emitter voltage) that can conduct is at least 0.65V. Therefore, the saturation voltage drop of the Darlington transistor is the sum of Q3's Vce3 and Q4's Vbe4, which is at least 0.8V. For example, the Darlington chip ULN2003 has a typical saturation voltage drop of 0.9-1.2V given in its specification sheet.

[0019] Given the significant conduction losses of the Darlington diodes currently used to drive tapped stepper motors, which hinder energy conservation, this application provides a novel drive system that replaces the traditional Darlington circuit with a first circuit to reduce the power consumption of the drive system, and thus the power consumption of the entire HVAC equipment. Furthermore, the tapped unipolar stepper motors in conventional electronic valves are replaced with stepper motors. The number of wiring harnesses in the replaced stepper motors is reduced from five to four, and the stator coils of the stepper motors are reduced (e.g., by half) compared to existing tapped stepper motors, contributing to reduced size, weight, and cost.

[0020] In addition to being provided in electronic devices such as electronic valves, the stepper motor in this application can also be provided in other electronic devices, for example, a damper or an electric pump, etc. It can also be provided independently of the electronic device.

[0021] If the electronic device is an air conditioning valve, the stepper motor controls the valve opening. If the electronic device is a damper, the stepper motor controls the rotation angle of the air guide plate in the damper mechanism. If the electronic device is an electric pump, the stepper motor controls the pump body (such as a centrifugal pump) to achieve fluid transportation.

[0022] The air conditioning valve is one of an electronic expansion valve, a multi-way reversing valve, a bypass valve, and a pilot valve. The multi-way reversing valve includes but is not limited to a three-way reversing valve, a four-way reversing valve, a seven-way reversing valve, and an eight-way reversing valve.

[0023] In one possible implementation, the aforementioned drive system may be a drive system for an electronic expansion valve. The electronic expansion valve includes a stepper motor comprising a permanent magnet rotor and a stator. The stator is disposed around the permanent magnet rotor and includes a first coil and a second coil. The permanent magnet rotor is located within a magnetic field generated by energizing the first and second coils according to control requirements. Furthermore, the electronic expansion valve includes a valve core and a transmission component. The valve core serves as an actuator. The step rotation of the permanent magnet rotor is converted into movement of the transmission component, which drives the valve core.

[0024] In another possible embodiment, the drive system may be a drive system in a damper, which includes a damper mechanism, which may include a horizontal damper component and / or a vertical damper component; in addition, the damper mechanism may also include a stepper motor, which includes a permanent magnet rotor and a stator; the horizontal damper component also includes a connecting rod mechanism and a horizontal air guide plate; the stepping rotation amount of the permanent magnet rotor is converted into the movement / rotation amount of the connecting rod mechanism, and the left and right air supply directions of the horizontal air guide plate are adjusted through the linkage of the connecting rod mechanism; the vertical damper component also includes a coupling or a gear set, and a vertical air guide plate, and the rotation amount of the permanent magnet rotor is converted into the rotation amount of the coupling or the gear set, and the up and down rotation angles of the vertical air guide plate are adjusted through the rotation of the coupling or the gear set.

[0025] The following will explain the application scenario of the stepper motor in the drive system to control the air conditioning valve. Figure 3 The drive system provided in the embodiment of the present application is described. The drive system includes: a drive circuit and two first circuits. The output end of the drive circuit is electrically connected to the input end of the first circuit. Each first circuit is used to connect to the stepper motor ( Figure 3 The two lead terminals of a stator coil in the MOTOR (in FIG) are connected to the drive circuit. The drive circuit is used to drive the two first circuit-controlled stepper motors to achieve opening control of the air conditioning valve. In some possible implementations, the stepper motor can be part of the drive system.

[0026] There are two first circuits, each with the same structure. Each first circuit is used to electrically connect two lead terminals of a stator coil in a stepper motor in an air conditioning valve, and each first circuit includes a first half-bridge and a second half-bridge with the same structure, for example, Figure 3 The first half bridge and the second half bridge connected to the AC stator coil form a first circuit, Figure 3 The first half-bridge and the second half-bridge connected to the BD stator coil form another first circuit. The input end of the first half-bridge is electrically connected to the drive circuit, and the output end of the first half-bridge is electrically connected to a lead terminal of a stator coil in the stepper motor. The input end of the second half-bridge is electrically connected to the drive circuit, and the output end of the second half-bridge is electrically connected to the other lead terminal of a stator coil in the stepper motor.

[0027] The first half bridge and the second half bridge both include an upper bridge arm and a lower bridge arm. The input end of the upper bridge arm of the first half bridge, the input end of the lower bridge arm of the second half bridge, the input end of the lower bridge arm of the first half bridge, and the input end of the upper bridge arm of the second half bridge are all electrically connected to the drive circuit. The upper bridge arm and the lower bridge arm of the first half bridge are connected to electrically connect to one lead terminal of the stator coil, and the upper bridge arm and the lower bridge arm of the second half bridge are connected to electrically connect to the other lead terminal of the stator coil. For example, for a circuit located at Figure 3 In the first circuit in the upper right middle section, the upper arm of the first half bridge is connected to pin 3 of the drive circuit, the lower arm of the first half bridge is electrically connected to pin 4 of the drive circuit, the upper arm of the second half bridge is electrically connected to pin 2 of the drive circuit, and the lower arm of the second half bridge is electrically connected to pin 1 of the drive circuit.

[0028] The first circuit includes a sub-module circuit, and the lower bridge arm of the first half bridge and the lower bridge arm of the second half bridge in the first circuit may both include a sub-module circuit. In addition, the upper bridge arm of the first half bridge and the upper bridge arm of the second half bridge in the first circuit both include switching transistors. The core feature of the sub-module circuit is to improve the current amplification capability and have a high current gain circuit, while reducing the saturation voltage drop problem of the traditional Darlington circuit. The conduction loss of the sub-module circuit is low, so that the power consumption of the lower bridge arm is only about 50% of that of the conventional Darlington tube, thereby significantly reducing the heat generated by the circuit, thereby reducing the power consumption of the drive system, and further reducing the power consumption of the entire HVAC equipment.

[0029] because Figure 3 The structure of the first circuit connecting the AC stator coil is the same as that of the first circuit connecting the BD coil. Here, the first circuit connecting the AC stator coil is used as an example for explanation. Figure 4 As shown, the circuit includes a first half-bridge and a second half-bridge of identical structure, each of which includes an upper arm and a lower arm. The upper arm of the first half-bridge includes Q2a and D2a, and the lower arm of the first half-bridge includes a submodule circuit. Similarly, the upper arm of the second half-bridge includes Q2c and D2c, and the lower arm of the second half-bridge includes a submodule circuit.

[0030] Each bridge arm includes a switching transistor (such as Q2a, Q4a, Q2c, or Q4c), and a diode is connected in parallel between the collector and emitter of the switching transistor, and the cathode of the diode faces the positive terminal of the power supply of the stepper motor (such as the P terminal), and the anode of the diode faces the negative terminal of the power supply of the stepper motor (such as the N terminal, that is, the ground terminal). For example, Figure 4 Diodes are connected in parallel between the collector and emitter of the switching transistors Q2a, Q4a, Q2c, and Q4c to protect them. When the driver circuit switches the switching transistors in the first circuit from on to off, assuming the current in the stator coil was previously flowing from A to C, this current continues after the switching transistors are turned off and cannot change direction instantaneously. At this point, the current from A to C can flow through D3a and D2c to the PN power supply. Without these diodes, the current from A to C in the coils would generate extremely high voltage or reverse voltage, damaging the switching transistors. Furthermore, the diodes connected in parallel between the collector and emitter of the switching transistors protect the switching transistors from damage due to high reverse voltage. Similarly, when the driver circuit switches the switching transistors in the first circuit from on to off, the current in the stator coil was previously flowing from C to A. This current continues after the switching transistors are turned off and cannot change direction instantaneously. At this point, the current from C to A can flow through D3c and D2a to the PN power supply.

[0031] Among them, the submodule circuit includes: a current limiting component, a first transistor (such as Figure 4Q3a or Q3c in the second transistor (such as Figure 4 Q4a or Q4c in the figure), wherein the collector of the first transistor and the collector of the second transistor are not interconnected, and the collector of the first transistor is connected to the current limiting component (such as Figure 4 The resistor R8a or R8c in the stepper motor is electrically connected to the power supply P terminal, and the collector of the second transistor is used to electrically connect the stator coil. Figure 4 The AC coil in the embodiment of the present invention. The current limiting component includes but is not limited to a current limiting resistor. For example, the current limiting component may also be a transistor used as a resistor.

[0032] In one possible implementation, the submodule circuit may further include a pull-down resistor (e.g. Figure 4 R9a or R9c in FIG. 1 ). The emitter of the first transistor and the base of the second transistor are both grounded through the pull-down resistor.

[0033] Submodule circuit and Figure 2 The conventional Darlington transistor shown in the figure differs in that the collector of Q3 is not connected to the collector of Q4, but is directly connected to the power supply terminal P through resistor R8. Since the collector of Q3 is independent of the collector of Q4, when Q3 is turned on, the power supply terminal P provides sufficient base current to Q4 through resistor R8 and Q3, and is not limited by the collector voltage of Q4. As a result, Q4 can be fully saturated, and the saturation voltage drop can be as low as 0.3-0.5V. This reduces the conduction loss of Q4 and the power consumption of the lower bridge arm is only about 50% of that of a conventional Darlington transistor, thereby significantly reducing the heat generated by the circuit.

[0034] In some possible implementations, the drive circuit includes a control circuit configured to control the stepper motor to rotate in a forward or reverse direction according to the aforementioned control method. Specifically, the stepper motor is controlled to rotate in a forward or reverse direction according to the control method of A→AB→B→BC→C→CD→D→DA→A or D→CD→C→BC→B→AB→A→DA→D. The present application may also implement stepper motor control using a pulse width modulation signal or a sinusoidal pulse width modulation signal.

[0035] The control circuit may include a processor, which may be an integrated circuit chip with signal processing capabilities. The processor may be a general-purpose processor, including a central processing unit (CPU), a network processor (NP), a graphics processing unit (GPU), an accelerated processing unit (Accelerated Processing Unit), a multimedia application processor (MAP), a microprocessor, etc.; it may also be a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components. Or the processor may also be any conventional processor, etc. In some possible implementations, the control circuit includes an MCU.

[0036] In some possible implementations, such as Figure 5 As shown, the driver circuit further includes a preamplifier circuit (also known as an auxiliary circuit) located between the control circuit and the first circuit. The input of the preamplifier circuit is electrically connected to the output of the control circuit, and the output of the preamplifier circuit is electrically connected to the input of the first circuit. The control circuit can drive the preamplifier circuit and thereby control the first circuit by outputting drive signals such as AH, CL, AL, CH, BH, DL, and BL, DH to the preamplifier circuit. AH and CL are the same drive signal A, AL and CH are the same drive signal C, BH and DL are the same drive signal B, and BL and DH are the same drive signal D. The control circuit can include four output terminals: a first output terminal, a second output terminal, a third output terminal, and a fourth output terminal. The first output terminal (AH, CL) is used to output a first drive signal, such as the AH and CL signals; the second output terminal (AL, CH) is used to output a second drive signal, such as the AL and CH signals; the third output terminal (BH, DL) is used to output a third drive signal, such as the BH and DL signals; and the fourth output terminal (BL, DH) is used to output a fourth drive signal, such as the BL and DH signals.

[0037] There are two pre-amplifier circuits, which correspond one-to-one to the two first circuits.

[0038] The preamplifier circuit can ensure that the primary circuit safely and efficiently drives the load (such as a stepper motor) and can also provide necessary isolation and protection functions. For example, the preamplifier circuit can be used for signal level conversion, current amplification and drive enhancement, and anti-common crosstalk.

[0039] Each preamplifier circuit includes a first half-bridge preamplifier circuit and a second half-bridge preamplifier circuit, wherein the structures of the first half-bridge preamplifier circuit and the second half-bridge preamplifier circuit can be identical. The input end of the first half-bridge preamplifier circuit is electrically connected to the control circuit, and the output end of the first half-bridge preamplifier circuit is electrically connected to the input end of the first half-bridge. Similarly, the input end of the second half-bridge preamplifier circuit is electrically connected to the control circuit, and the output end of the second half-bridge preamplifier circuit is electrically connected to the input end of the second half-bridge.

[0040] Since the structure of the first half-bridge pre-circuit and the structure of the second half-bridge pre-circuit can be the same, only one of them is described here. For example, the first half-bridge pre-circuit includes: a level shifting circuit and / or a current amplifying circuit, that is, in this case, the driving circuit includes not only the control circuit but also the level shifting circuit and / or the current amplifying circuit.

[0041] In some possible implementations, the first half-bridge pre-circuit can be used to drive the upper bridge arm in the first circuit after level shifting the first drive signal (such as AH, CL signals) and the third drive signal (such as BH, DL signals) output by the control circuit, and / or drive the lower bridge arm in the first circuit after current amplification of the second drive signal (such as AL, CH signals) and the fourth drive signal (such as BL, DH signals) output by the control circuit.

[0042] Among them, under a possible implementation method, the principle diagram of the connection between the front circuit and the first circuit is as follows: Figure 6 As shown, Figure 6 Q1a and R3a are the level shift circuit in the first half-bridge preamplifier circuit, and Q1c and R3c are the level shift circuit in the second half-bridge preamplifier circuit. Figure 6 The input end of the level shift circuit in the first half-bridge preamplifier circuit is electrically connected to the first output end of the control circuit (for outputting a first drive signal, such as AH and CL signals), and the output end of the level shift circuit in the first half-bridge preamplifier circuit is electrically connected to the upper left bridge arm in the first circuit. The input end of the level shift circuit in the second half-bridge preamplifier circuit is electrically connected to the second output end of the control circuit (for outputting a second drive signal, such as AL and CH signals), and the output end of the level shift circuit in the second half-bridge preamplifier circuit is electrically connected to the upper right bridge arm in the first circuit.

[0043] The upper bridge arm of the first circuit controls the conduction or cut-off of Q2 through level shifting of Q1 and R3, so that a separate driving power supply for Q2 is not needed (generally, the upper half bridge of a bridge circuit has a separate driving power supply, such as a bootstrap power supply).

[0044] Figure 6 The input end of the current amplification circuit in the first half bridge pre-circuit is connected with the second output end of the control circuit, and the output end of the current amplification circuit is connected with the left lower bridge arm in the first circuit. Figure 6 Q3a and R9a in the first half bridge pre-circuit are the current amplification circuit, and Q3c and R9c can be the current amplification circuit of the second half bridge. This part can be a common part of the pre-circuit and the sub-module circuit. By multiplexing this structure, the size and cost of the circuit can be reduced.

[0045] In addition to the level shifting circuit and / or the current amplification circuit, the first half bridge pre-circuit can also include a voltage dividing circuit, a filter circuit, etc. Figure 6 The two resistors in series in the first half bridge pre-circuit are a voltage dividing circuit, for example, R1a and R2a are a voltage dividing circuit, similarly, R3a, R4a are a voltage dividing circuit, R6a, R7a are a voltage dividing circuit, and R5a, R6a are a voltage dividing circuit. Among them, R5a, C2a or C2a, R6a are a filter circuit.

[0046] In some possible implementations, the pre-circuit can include a common protection circuit, that is, at this time, the driving circuit includes a common protection circuit. The common protection circuit is connected between the upper bridge arm and the lower bridge arm of the first circuit. The common protection circuit is used to prevent (or prevent) the upper bridge arm and the lower bridge arm of the first circuit from being common. For a bridge circuit, once the upper bridge arm and the lower bridge arm are simultaneously turned on, a short circuit between the P-N power supply and a large current will be generated, which will cause the switching triode in the upper and lower bridge arms to be damaged by overcurrent or the Vm power supply to be damaged.

[0047] In some possible implementations, as shown in Figure 7As shown, the common protection circuit includes: a third transistor (such as Q1), a diode (such as D1), and a first resistor (such as R5). The base of the third transistor Q1 is connected to the output end of the control circuit in the drive circuit (such as the AH, CL end, or the AL, CH end), and the emitter of the third transistor Q1 is grounded. In some embodiments, the base of the third transistor Q1 can also be electrically connected to the emitter of the third transistor Q1 through a current-limiting resistor (such as R2a or R2c) and grounded, and the collector of the third transistor Q1 is electrically connected to the upper bridge arm of the first circuit. One end of the first resistor R5 is electrically connected to the output end of the control circuit (such as the AL, CH end, or the AH, CL end), the other end of the first resistor R5 is electrically connected to the anode of the diode R5, the cathode of the diode R5 is electrically connected to the collector of the third transistor Q1, and the other end of the first resistor R5 is also electrically connected to the input end of the sub-module circuit. Figure 7 Q1a, D1a, and R5a form a common protection circuit, and Q1c, D1c, and R5c form another common protection circuit. The common protection circuit of the first half bridge is electrically connected to the AH and CL terminals of the control circuit, and the common protection circuit of the second half bridge is electrically connected to the AL and CH terminals of the control circuit.

[0048] If the driving circuit further includes a level shift circuit, the common protection circuit and the level shift circuit share the third transistor, thereby reducing the volume and cost of the circuit. Figure 7 The example shown is a schematic diagram of a front-end circuit that includes both a level shift circuit and a common protection circuit. Figure 6 By adding D1, Q1 is saturated when the upper arm is turned on, and the node voltage between R5 and R6 is clamped to about 1.0V through D1. Then, through R6 and R7, the voltage at the base of Q3 is made no higher than 0.6V. The input voltage for Q3 and Q4 to turn on must be at least 1.1V. In this way, regardless of whether the input of the lower arm is high at this moment, Q3 and Q4 can be in the cut-off state, thus avoiding the situation where Q4 and Q2 are turned on at the same time.

[0049] Some possible implementations, such as Figure 8As shown, the common protection circuit includes: a third transistor (such as Q1), a fourth transistor (such as Q5), a first resistor (such as R5), and a second resistor (such as R10). The base of the third transistor Q1 is connected to the output terminal (such as AH, CL terminal) of the control circuit in the driving circuit, the emitter of the third transistor Q1 is grounded, in some embodiments, the base of the third transistor Q1 can also be electrically connected to the emitter of the third transistor Q1 through the current-limiting resistor R2 and grounded, and the collector of the third transistor Q1 is electrically connected to the upper bridge arm of the first circuit. One end of the first resistor R5 is electrically connected to the output terminal (such as AL, CH terminal) of the control circuit, the other end of the first resistor R5 is electrically connected to the collector of the fourth transistor Q5, and the other end of the first resistor R5 is also electrically connected to the input terminal of the sub-module circuit. One end of the second resistor R10 is connected to the output terminal (such as AH, CL terminal) of the control circuit, and the other end of the second resistor R10 is electrically connected to the base of the fourth transistor Q5, and the emitter of the fourth transistor Q5 is grounded.

[0050] If the driving circuit further includes a level shift circuit, the common protection circuit shares the third transistor Q1 with the level shift circuit, wherein, Figure 8 In the example shown, the pre-circuit simultaneously includes the level shift circuit and the common protection circuit. Compared with the pre-circuit shown in Figure 7 The common protection circuit shown can be replaced by Figure 8 Q5 and R10 in Figure 7 When the upper bridge arm has a driving signal, Q1 is saturated, Q2 is turned on; at the same time, Q5 is also saturated, clamps the input of the lower bridge arm to below 0.5V, and Q4 is cut off, thereby avoiding the common of the upper bridge arm and the lower bridge arm. Figure 8 Only the schematic diagram of the connection between the first half-bridge pre-circuit in the pre-circuit and the first circuit is shown, and for the second half-bridge in the first circuit, the connection mode is similar to Figure 8 .

[0051] In some possible embodiments, Figure 8 The voltage dividing circuit, the filtering circuit, etc. in the pre-circuit shown can be omitted, and at the same time, the level shift circuit, the common protection circuit, and the current amplification circuit can not exist at the same time. Therefore, the pre-circuit shown in Figure 8 cannot be understood as a limitation of the present application.

[0052] In some possible implementations, the aforementioned drive circuit and the first circuit may be independent of each other. In some possible implementations, at least a portion of the drive circuit may be integrated with the first circuit. In this case, the entire drive circuit may be integrated with the first circuit, or a portion of the drive circuit may be integrated with the first circuit, while the remaining portion is separate from the first circuit. The drive circuit may include the aforementioned control circuit and preamplifier circuit, which may in turn include a level shifter circuit, a current amplifier circuit, a common protection circuit, etc. In this case, at least a portion of the drive circuit integrated with the first circuit may be at least one of the control circuit, the level shifter circuit, the current amplifier circuit, and the common protection circuit. For example, the level shifter circuit, the current amplifier circuit, and the common protection circuit may all be integrated with the first circuit and separate from the control circuit. In another example, the common protection circuit in the preamplifier circuit may be integrated with the first circuit and separate from the control circuit, while the level shifter circuit and current amplifier circuit in the preamplifier circuit may be separate from the first circuit. In another example, the first circuit may be integrated with the control circuit and separate from the preamplifier circuit.

[0053] In one embodiment, the remaining circuits (such as the preamplifier circuit) in the driving circuit except the control circuit are integrated with the first circuit. In this case, the circuit of the remaining circuits in the integrated driving circuit and the first circuit can be referred to as the first driving circuit. The circuit diagram in this case is as follows: Figure 9 In this embodiment, Figure 9 The schematic diagram of the first driving circuit shown can be as follows Figure 6 、 Figure 7 or Figure 8 shown.

[0054] In some possible implementations, the driver circuit includes at least a portion of the integrated circuits of various circuits. For example, the driver circuit includes at least a portion of the integrated circuits of a control circuit, a level shift circuit, a current amplifier circuit, a common protection circuit, and other circuits. For example, the level shift circuit, current amplifier circuit, and common protection circuit of the driver circuit may be integrated and separate from the control circuit. In another example, the level shift circuit and current amplifier circuit of the driver circuit may be integrated and separate from the control circuit and common protection circuit.

[0055] The embodiment of the present application further provides a circuit board having a first circuit. The schematic diagram of the first circuit is shown in the above Figure 4 As shown, the first circuit provided in the embodiment of the present application has the same implementation principle and technical effects as the first circuit in the aforementioned drive system embodiment. For the sake of brief description, for parts not mentioned in the first circuit embodiment, please refer to the corresponding content in the aforementioned drive system embodiment.

[0056] An embodiment of the present application further provides a HVAC device, which includes a first drive system and a flow driving mechanism. The structure of the first drive system is the same as that of the above-mentioned drive system and will not be repeated here.

[0057] The first drive system is electrically connected to a stepper motor in a flow driving mechanism; the flow driving mechanism is used to drive the flow of the medium in the HVAC equipment. In some embodiments, the stepper motor can belong to the first drive system.

[0058] In the embodiments of the present application, a flow-driving mechanism refers to a mechanism for driving the flow of a medium within the HVAC equipment, and may be, for example, but not limited to, a compressor, blower, or fan. In the embodiments of the present application, a medium refers to a refrigerant or gas flowing within the HVAC equipment to achieve heat exchange, ventilation, humidification, or dehumidification functions.

[0059] The HVAC equipment provided in the embodiments of the present application includes, but is not limited to, air conditioners, humidification and dehumidification equipment (such as humidifiers, dehumidifiers, etc.), and ventilation equipment (such as fans, fume hoods, fresh air systems, etc.). For example, when the HVAC equipment is an air conditioner, the flow driving mechanism may be a compressor. In addition, the air conditioner may also include a condenser, an air conditioning valve (which may be an electronic expansion valve), a second drive system, and an evaporator. The compressor drives the refrigerant in the air conditioner, and realizes the cooling or heating function through the condenser, evaporator, and air conditioning valve. The second drive system in the HVAC equipment (in this case, the air conditioner) is electrically connected to the stepper motor in the electronic expansion valve, and the stepper motor in the electronic expansion valve is used to control the opening of the valve body in the electronic expansion valve. The structure of the second drive system in the present application is the same as the structure of the first drive system described above.

[0060] For example, if the HVAC equipment is a humidifier, the flow-displacing mechanism can be a fan or blower. The humidifier can also include a damper mechanism and a second drive system, which uses the fan or blower to dissipate the vaporized liquid through the damper mechanism's air deflector. The second drive system in the HVAC equipment (in this case, the humidifier) ​​is connected to the damper mechanism's stepper motor, which controls the rotation angle of the air deflector.

[0061] For example, if the HVAC equipment is a dehumidifier, fume hood, or fresh air system, the airflow mechanism can be a fan. The HVAC equipment can also include a damper mechanism and a second drive system. The fan drives air out of the air deflector, achieving air exchange. The second drive system in the HVAC equipment (in this case, a dehumidifier, fume hood, or fresh air system) is connected to the damper mechanism's stepper motor, which controls the rotation angle of the air deflector.

[0062] For example, if the HVAC equipment is an air conditioner, the flow-driving mechanism could be an electric pump within the HVAC equipment. This electric pump consists of a stepper motor and a pump body (such as a centrifugal pump). The stepper motor is connected to the pump body to drive the pump body and achieve fluid transportation. Furthermore, an air conditioner may also include a condenser and an evaporator. The electric pump can be used to transport chilled water / cooling water circulating between the condenser and the evaporator.

[0063] It should be noted that the various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same and similar parts between the various embodiments can be referenced to each other.

[0064] In addition, the functional modules in each embodiment of the present application can be integrated together to form an independent part, or each module can exist independently, or two or more modules can be integrated to form an independent part.

[0065] The principles and implementation methods of the present invention have been described above using specific examples. The description of the above embodiments is only intended to help understand the technical solutions and core concepts of the present invention. It should be noted that those skilled in the art may make various improvements and modifications to the present invention without departing from the principles of the present invention, and such improvements and modifications also fall within the scope of protection of the present invention.

Claims

1. A drive system, characterized in that: include: Two first circuits, each of the first circuits is used to electrically connect two lead terminals of a stator coil in a stepping motor, and each of the first circuits includes a submodule circuit; A driving circuit, used for driving the two first circuits to control the stepping motor; The submodule circuit includes: a current limiting component, a first transistor and a second transistor; the collector of the first transistor and the collector of the second transistor are not interconnected, and the collector of the first transistor is connected to the power supply of the stepping motor through the current limiting component, and the collector of the second transistor is used to electrically connect to the stator coil.

2. The drive system according to claim 1, characterized in that The first circuit includes: a first half-bridge, wherein an input end of the first half-bridge is used to electrically connect to the drive circuit, an output end of the first half-bridge is used to electrically connect to a lead terminal of a stator coil in the stepping motor, the first half-bridge includes an upper bridge arm and a lower bridge arm, the lower bridge arm of the first half-bridge includes the sub-module circuit, and the upper bridge arm of the first half-bridge includes a switching transistor; A second half bridge; the input end of the second half bridge is used to electrically connect to the drive circuit, the output end of the second half bridge is used to electrically connect to another lead terminal of a stator coil in the stepping motor, the second half bridge includes an upper bridge arm and a lower bridge arm, the lower bridge arm of the second half bridge includes the sub-module circuit, and the upper bridge arm of the second half bridge includes a switching transistor.

3. The drive system according to any one of claims 1 to 2, characterized in that: The driving circuit includes: a control circuit and a level shift circuit; The input end of the level shift circuit is electrically connected to the output end of the control circuit, and the output end of the level shift circuit is electrically connected to the upper bridge arm in the first circuit; The level shift circuit is used to drive the upper bridge arm in the first circuit after performing level shift on the driving signal output by the control circuit.

4. The drive system according to claim 3, characterized in that: The driving circuit includes: a common protection circuit; The common protection circuit is connected between the upper bridge arm and the lower bridge arm of the first circuit, and is used to prevent the upper bridge arm and the lower bridge arm of the first circuit from being connected in common.

5. The drive system according to claim 4, characterized in that: The common protection circuit includes: a third transistor, a diode, and a first resistor; The base of the third transistor is electrically connected to the output end of the control circuit in the driving circuit, the emitter of the third transistor is grounded, and the collector of the third transistor is electrically connected to the upper bridge arm of the first circuit; One end of the first resistor is electrically connected to the output end of the control circuit, the other end of the first resistor is electrically connected to the anode of the diode, the cathode of the diode is electrically connected to the collector of the third transistor, and the other end of the first resistor is also electrically connected to the input end of the sub-module circuit.

6. The drive system according to claim 4, characterized in that: The common protection circuit includes: a third transistor, a fourth transistor, a first resistor, and a second resistor; The base of the third transistor is electrically connected to the output end of the control circuit in the driving circuit, the emitter of the third transistor is grounded, and the collector of the third transistor is electrically connected to the upper bridge arm of the first circuit; One end of the first resistor is electrically connected to the output end of the control circuit, the other end of the first resistor is electrically connected to the collector of the fourth transistor, and the other end of the first resistor is also electrically connected to the input end of the submodule circuit; One end of the second resistor is electrically connected to the output end of the control circuit, the other end of the second resistor is electrically connected to the base of the fourth transistor, and the emitter of the fourth transistor is grounded.

7. The drive system according to claim 5 or 6, characterized in that: When the driving circuit further includes a level shift circuit, the common protection circuit and the level shift circuit share the third transistor.

8. The drive system according to claim 7, characterized in that: At least part of the driving circuit is integrated with the first circuit, or the driving circuit is separate from the first circuit or the driving circuit includes at least part of the circuits integrated.

9. The drive system according to claim 7, characterized in that: The drive system is a drive system in an electronic expansion valve, which includes a stepper motor; the stepper motor includes a permanent magnet rotor and a stator; the stator is arranged around the permanent magnet rotor, the stator includes a first coil and a second coil, and the permanent magnet rotor is located in a magnetic field generated by energizing the first and second coils according to control requirements; the electronic expansion valve also includes a valve core and a transmission component, the valve core is an actuator, the step rotation amount of the permanent magnet rotor is converted into the movement amount of the transmission component, and the transmission component drives the valve core to move.

10. The driving system according to claim 7, characterized in that The drive system is a drive system in a damper, wherein the damper comprises a damper mechanism, including a horizontal damper component and / or a vertical damper component; the damper mechanism further comprises a stepper motor, and the stepper motor comprises a permanent magnet rotor and a stator; The horizontal damper component further includes a connecting rod mechanism and a horizontal air guide plate; the step rotation amount of the permanent magnet rotor is converted into the movement amount / rotation amount of the connecting rod mechanism, and the left and right air supply directions of the horizontal air guide plate are adjusted through the linkage of the connecting rod mechanism; The vertical air door component also includes a coupling or a gear set, and a vertical air guide plate. The rotation amount of the permanent magnet rotor is converted into the rotation amount of the coupling or the gear set, and the up and down rotation angle of the vertical air guide plate is adjusted by the rotation of the coupling or the gear set.

11. A circuit board having a first circuit, characterized in that: include: a first half-bridge, wherein an input end of the first half-bridge is used to electrically connect to a drive circuit, an output end of the first half-bridge is used to electrically connect to a lead terminal of a coil in a stepping motor, the first half-bridge includes an upper bridge arm and a lower bridge arm, the lower bridge arm of the first half-bridge includes a submodule circuit, and the upper bridge arm of the first half-bridge includes a switching transistor; Second half bridge; The input end of the second half-bridge is used to electrically connect to the drive circuit, and the output end of the second half-bridge is used to electrically connect to the other lead terminal of a stator coil in the stepping motor. The second half-bridge includes an upper bridge arm and a lower bridge arm, the lower bridge arm of the second half-bridge includes the sub-module circuit, and the upper bridge arm of the second half-bridge includes a switching transistor; The submodule circuit includes: a current limiting component, a first transistor and a second transistor; the collector of the first transistor and the collector of the second transistor are not interconnected, and the collector of the first transistor is connected to the power supply of the stepping motor through the current limiting component, and the collector of the second transistor is used to connect to the stator coil.

12. A HVAC equipment, characterized in that: It includes a first driving system and a flow driving mechanism, wherein the first driving system is connected to a stepping motor in the flow driving mechanism, and the flow driving mechanism is used to drive the medium flow in the HVAC equipment; The first driving system includes a driving circuit and two first circuits; Each of the first circuits is used to electrically connect two lead terminals of a stator coil in the stepping motor, and each of the first circuits includes a sub-module circuit; The driving circuit is used to drive the two first circuits to control the stepping motor; The submodule circuit includes: a current limiting component, a first transistor and a second transistor; the collector of the first transistor and the collector of the second transistor are not interconnected, and the collector of the first transistor is connected to the power supply of the stepping motor through the current limiting component, and the collector of the second transistor is used to connect to the stator coil.

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