CN216437092U

CN216437092U - High-voltage direct-current motor driving circuit and driving circuit board thereof

Info

Publication number: CN216437092U
Application number: CN202122823015.6U
Authority: CN
Inventors: 罗运欢; 曹洁; 高超; 陈浩; 高梦奇
Original assignee: TCL Home Appliances Hefei Co Ltd
Current assignee: TCL Home Appliances Hefei Co Ltd
Priority date: 2021-11-16
Filing date: 2021-11-16
Publication date: 2022-05-03
Anticipated expiration: 2031-11-16

Abstract

The application relates to a high-voltage direct-current motor driving circuit and a driving circuit board thereof. When the motor to be driven needs to rotate forwards, the circuit maintains the connection of the first non-loaded relay and the power supply through the processor, controls the second non-loaded relay to be switched to be connected with the ground wire, and controls the loaded relay to enable the second electric signal end to be conducted with the second non-loaded relay after the second non-loaded relay is switched to be connected with the ground wire, so that the forward rotation driving of the motor is realized; when waiting to drive motor and need reversing, maintain second non-load relay through the treater and connect the power, control first non-load relay switch connection ground wire, and after first non-load relay switch connection ground wire, control load relay so that switch on between second signal of telecommunication end and the second non-load relay, realize the motor reversal drive, the quantity that has reduced small-size high-power direct current relay, and is with low costs, and there is not special requirement to the distance between design position and the device, reduces product design cost, and reduced the circuit fault rate.

Description

High-voltage direct-current motor driving circuit and driving circuit board thereof

Technical Field

The application relates to the technical field of driving circuits, in particular to a high-voltage direct-current motor driving circuit and a driving circuit board thereof.

Background

At present, most of products such as refrigerators with an ice making function can realize the functions of crushing and taking ice by controlling the positive and negative rotation of a brush direct current motor. The brush direct current motor is generally driven by high-voltage direct current, a common relay cannot drive a high-voltage direct current load, and a plurality of small high-power direct current relays (with direct-current high-voltage on-load switching capacity) are generally adopted to drive the brush direct current motor. The four small high-power relays are separately controlled to realize the direction control of the motor current, so that the forward and reverse rotation of the motor are controlled. The small high-power relay is internally provided with a magnet, so that the small high-power relays are mutually repelled and absorbed, and under the action of mutual magnetic fields, parts in the small high-power relay are deformed, parameters are changed and damaged, and the performance is reduced. Therefore, the layout area needs to be increased and the distance between the relays needs to be increased during circuit design. In addition, the small high-power relay has high cost, and one small high-power relay (namely the relay with direct-current high-voltage loaded switching capability) is three times that of a common relay (namely the relay with non-direct-current loaded switching capability). A plurality of (such as 4) small-sized high-power relays are used in the traditional motor driving mode, so that the cost of the whole machine is greatly increased, and the economic practicability and the competitiveness of the product are reduced.

In the implementation process, the inventor finds that at least the following problems exist in the conventional technology: in the traditional motor driving mode, the used driving control circuit has the defects of large number of devices, complex circuit structure, large circuit board volume and high cost.

SUMMERY OF THE UTILITY MODEL

Therefore, it is necessary to solve the problems of large number of used drive control circuit devices, complex circuit structure, large circuit board volume and high cost in the conventional motor drive mode, and provide a high voltage direct current motor drive circuit and a drive circuit board thereof, which can optimize the existing brushless high voltage direct current motor drive circuit, reduce the number of drive I/O ports of a single chip microcomputer, reduce the product design cost, simplify the circuit structure, provide convenience for later hardware design, and reduce the circuit failure rate.

In order to achieve the above object, the embodiment of the utility model provides a high voltage direct current motor drive circuit, high voltage direct current motor drive circuit includes:

the first off-load relay is coupled with the processor and configured to control a first electric signal end of the motor to be driven to switch and connect the ground wire or the power supply according to a received first control signal transmitted by the processor;

the second off-load relay is coupled with the processor and configured to control a second electric signal end of the motor to be driven to switch and connect the ground wire or the power supply according to a received second control signal transmitted by the processor;

the on-load relay is coupled with the processor and is configured to control the connection or disconnection between a second electric signal end of the motor to be driven and the second off-load relay according to a received third control signal transmitted by the processor;

the processor is configured to maintain the first non-loaded relay connected with the power supply and control the second non-loaded relay to be switched to be connected with the ground wire if the motor to be driven needs to rotate forwards, and control the loaded relay to enable the second electric signal end of the motor to be driven to be conducted with the second non-loaded relay after the second non-loaded relay is switched to be connected with the ground wire; the processor is also configured to maintain the second non-loaded relay to be connected with the power supply if the motor to be driven needs to rotate reversely, control the first non-loaded relay to be switched to be connected with the ground wire, and control the loaded relay to enable the second electric signal end of the motor to be driven to be conducted with the second non-loaded relay after the first non-loaded relay is switched to be connected with the ground wire.

In one embodiment, the first off-load relay comprises a first control terminal and a first selection switch; the first control end is coupled with the first output end of the processor; the first end of the first selection switch is connected with a first electric signal end of the motor to be driven; the first control end is configured to control the second end of the first selection switch to be connected with the power supply or the ground wire according to the received first control signal transmitted by the processor.

In one embodiment, the high-voltage direct current motor driving circuit further comprises a first freewheeling diode; the first off-load relay further comprises a first power supply end; the negative pole of the first fly-wheel diode is connected with the first power supply end, and the positive pole of the first fly-wheel diode is connected with the first control end.

In one embodiment, the second off-load relay comprises a second control terminal and a second selection switch; the second control end is coupled with the second output end of the processor; the first end of the second selector switch is used for connecting the on-load relay; the second control terminal is configured to control the second terminal of the second selection switch to be connected with the ground line or the power supply according to the received second control signal transmitted by the processor.

In one embodiment, the high-voltage direct current motor driving circuit further comprises a second freewheeling diode; the second off-load relay further comprises a second power supply end; the negative electrode of the second fly-wheel diode is connected with the second power supply end, and the positive electrode of the second fly-wheel diode is connected with the second control end.

In one embodiment, the on-load relay comprises a third control end and a third selection switch; the third control end is coupled with the third output end of the processor; the first end of the third selector switch is used for connecting a second electric signal end of the motor to be driven; the third control end is configured to control the second end of the third selection switch to be communicated with the first end of the second selection switch according to a received third control signal transmitted by the processor, so that the second electric signal end of the motor to be driven is conducted with the second non-load relay.

In one embodiment, the high-voltage direct current motor driving circuit further comprises a third freewheeling diode; the on-load relay further comprises a third power supply end; the negative electrode of the third freewheeling diode is connected with the third power supply end, and the positive electrode of the third freewheeling diode is connected with the third control end.

In one embodiment, the high-voltage direct current motor driving circuit further comprises a Darlington transistor component; the input end of the Darlington transistor assembly is connected with the processor, and the output end of the Darlington transistor assembly is respectively connected with the first non-loaded relay, the second non-loaded relay and the loaded relay.

In one embodiment, the high-voltage direct-current motor driving circuit further comprises a decoupling capacitor; the decoupling capacitor is connected between a power supply terminal of the Darlington transistor component and a grounding terminal of the Darlington transistor component.

On the other hand, the embodiment of the utility model provides a still provides a high voltage direct current motor drive circuit's drive circuit board, including circuit substrate to and set up on circuit substrate as above-mentioned arbitrary high voltage direct current motor drive circuit.

One of the above technical solutions has the following advantages and beneficial effects:

in each embodiment of the high-voltage direct-current motor driving circuit, the processor is coupled and connected through a first off-load relay, a second off-load relay and a loaded relay; when the motor to be driven needs to rotate forwards, the processor maintains the first non-loaded relay to be connected with the power supply, controls the second non-loaded relay to be switched to be connected with the ground wire, and controls the loaded relay to enable the second electric signal end of the motor to be driven to be conducted with the second non-loaded relay after the second non-loaded relay is switched to be connected with the ground wire, so that the motor to be driven can rotate forwards; when the motor to be driven needs to be reversely rotated, the processor maintains the second non-loaded relay to be connected with the power supply, controls the first non-loaded relay to be switched and connected with the ground wire, and controls the loaded relay to enable the second electric signal end of the motor to be driven to be conducted with the second non-loaded relay after the first non-loaded relay is switched and connected with the ground wire, so that the reverse rotation driving of the motor to be driven is realized. This application reduces small-size high-power direct current relay's quantity through optimizing current brushless high voltage direct current motor drive circuit, on the basis that only uses a small-size high-power direct current relay, uses 2 direct current relays (no direct current area year switching capability) that have a set of conversion capability through the collocation and realizes switching motor current's direction of operation. The control circuit relays are synchronously reduced, the direct-current group of conversion on-load relays are low in cost and free of magnetism, no special requirements are required for the distance between a design position and a device, advantages are provided for the cost of design boards and devices in the later stage, the workload of developers is reduced, the design cost of products is reduced, and the circuit failure rate is reduced.

Drawings

Fig. 1 is a circuit diagram of a conventional high-voltage dc motor driving circuit.

Fig. 2 is a circuit schematic diagram of a driving circuit of a high-voltage direct-current motor in an embodiment of the present application.

Fig. 3 is a circuit schematic diagram of a driving circuit of a high-voltage direct-current motor in an embodiment of the present application.

Detailed Description

To facilitate an understanding of the present application, the present application will now be described more fully with reference to the accompanying drawings. Preferred embodiments of the present application are shown in the drawings. This application may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.

It will be understood that when an element is referred to as being "connected" to another element, it can be directly connected to the other element and be integral therewith, or intervening elements may also be present. The terms "mounted," "one end," "the other end," and the like are used herein for illustrative purposes only.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein in the description of the present application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

In a traditional high-voltage direct-current motor driving circuit, as shown in fig. 1, a single chip microcomputer outputs high levels through 4I/O ports (i.e., I/O1, I/O2, I/O3 and I/O4) to control on and off of four on-load direct-current relays (i.e., RL4, RL5, RL6 and RL7) respectively. When the I/O1 and the I/O2 output high level, the RL4 and the RL5 relays are conducted and attract; the power supply DC170V reaches the RL5 through the RL4, the pin 1 of the motor and the pin 2 of the motor, and reaches the ground wire PGND to form a loop after being sucked by the RL5, so that the forward rotation driving of the motor M is realized. When the I/O3 and the I/O4 output high level, the RL6 and the RL7 are conducted for pull-in; the power supply DC170V reaches the RL7 through the RL6, the pin 2 of the motor and the pin 1 of the motor, and after the RL7 is sucked, the power supply DC reaches the ground wire PGND to form a loop, so that the reverse driving of the motor M is realized. Thereby realizing the positive rotation and the reverse rotation of the motor M by controlling the current direction of the motor M. Among the above-mentioned traditional motor drive mode, through using four small-size high-power relays to separately control, the drive control circuit device that uses is in large quantity, circuit structure is complicated, and is with high costs, and small-size high-power relay inside has magnet, will have the condition of repelling each other and absorbing between the small-size high-power relay, under the effect in mutual magnetic field, lead to the inside part of small-size high-power relay to warp, parameter variation and damage, the performance descends, need consider increase the floorslab area when circuit design, increase interval between the relay, make the circuit board bulky.

Referring to fig. 2 to fig. 3, a high-voltage dc motor driving circuit and a driving circuit board thereof according to an embodiment of the present application will be described in detail with reference to the accompanying drawings.

In order to solve the problems of large number of used drive control circuit devices, complex circuit structure, large circuit board volume and high cost in the conventional motor drive mode, in one embodiment, as shown in fig. 2, a high voltage direct current motor drive circuit is provided, which includes a first non-load relay 110, a second non-load relay 120 and a load relay 130; the first off-load relay 110 is coupled to the processor 140 and configured to control the first electrical signal terminal of the motor to be driven to switch to connect the ground wire 150 or the power supply 160 according to the received first control signal transmitted by the processor 140; the second off-load relay 120 is coupled to the processor 140 and configured to control the second electrical signal terminal of the motor to be driven to switch to the ground wire 150 or the power supply 160 according to the received second control signal transmitted by the processor 140; the on-load relay 130 is coupled to the processor 140, and configured to control the second electrical signal terminal of the motor to be driven and the second off-load relay 120 to be turned on or off according to the received third control signal transmitted by the processor 140. The processor 140 is configured to maintain the first off-load relay 110 connected to the power supply 160, control the second off-load relay 120 to switch over to the ground 150, and control the on-load relay 130 to conduct the second electrical signal terminal of the motor to be driven and the second off-load relay 120 after the second off-load relay 120 switches over to the ground 150 if the motor to be driven needs to rotate forward; the processor 140 is further configured to maintain the second off-load relay 120 connected to the power source 160 if the motor to be driven needs to rotate reversely, control the first off-load relay 110 to switch the connection ground 150, and control the on-load relay 130 to conduct the second electrical signal terminal of the motor to be driven and the second off-load relay 120 after the first off-load relay 110 switches the connection ground 150.

The first off-load relay 110 refers to a relay without dc high voltage on-load switching capability, and the first off-load relay 110 may be a low-cost dc relay. The second off-load relay 120 refers to a relay that does not have dc high voltage on-load switching capability, e.g., the second off-load relay 120 may be a low cost dc relay. The on-load relay 130 refers to a relay with dc high voltage on-load switching capability, for example, the on-load relay 130 may be a small high power dc relay. The motor to be driven is a high-voltage direct-current motor and comprises a first electric signal end and a second electric signal end, and when a driving current signal is input from the first electric signal end of the motor to be driven and is output from the second electric signal end, the motor to be driven realizes positive rotation; when the driving current signal is input from the second electric signal end of the motor to be driven and is output from the first electric signal end, the motor to be driven is reversed. The motor to be driven can be applied to household appliances such as refrigerators, and the functions of crushing and taking ice can be realized by controlling the forward rotation and the reverse rotation of the motor to be driven. The processor 140 refers to a processor 140 having signal processing and signal transmission functions, for example, the processor 140 may be a single chip microcomputer.

Specifically, based on the first off-load relay 110 being coupled to the processor 140, the processor 140 may transmit a first control signal to the first off-load relay 110, and the first off-load relay 110 may control the first electrical signal terminal of the motor to be driven to switch the ground connection 150 or the power supply 160 according to the received first control signal. For example, in the initial state of the first off-load relay 110, the first electrical signal terminal of the motor to be driven is connected to the power supply 160, and when the first off-load relay 110 receives the first control signal, the first electrical signal terminal of the motor to be driven can be controlled to be switched from the power supply 160 to the ground 150. Based on the second off-load relay 120 coupled to the processor 140, the processor 140 may transmit a second control signal to the second off-load relay 120, and the second off-load relay 120 may control the second electrical signal terminal of the motor to be driven to switch between the ground line 150 and the power source 160 according to the received second control signal. For example, in the initial state of the second off-load relay 120, the second electrical signal terminal of the motor to be driven is connected to the power supply 160, and when the second off-load relay 120 receives the second control signal, the second electrical signal terminal of the motor to be driven can be controlled to be switched from the connection power supply 160 to the connection ground 150. Based on the on-load relay 130 being coupled with the processor 140, the processor 140 may transmit a third control signal to the on-load relay 130 after the first off-load relay 110 switches to connect the ground line 150 or after the second off-load relay 120 switches to connect the ground line 150, and the on-load relay 130 controls the connection or disconnection between the second electrical signal terminal of the motor to be driven and the second off-load relay 120 according to the received third control signal transmitted by the processor 140; for example, in the initial state of the on-load relay 130, the second electrical signal terminal of the motor to be driven and the second off-load relay 120 are disconnected, and when the on-load relay 130 receives the third control signal, the second electrical signal terminal of the motor to be driven and the second off-load relay 120 may be controlled to be connected.

Further, when the motor to be driven needs to rotate forward, the processor 140 maintains the first off-load relay 110 connected to the power supply 160, so that the first electrical signal end of the motor to be driven is connected to the power supply 160, the processor 140 transmits a second control signal to the second off-load relay 120, so that the second off-load relay 120 controls the second off-load relay 120 to switch over to be connected to the ground 150 according to the second control signal, the processor 140 transmits a third control signal to the on-load relay 130 after the second off-load relay 120 switches over to be connected to the ground 150, so as to control the on-load relay 130, so that the second electrical signal end of the motor to be driven and the second off-load relay 120 are conducted, so that the motor to be driven forms a complete working loop, and current signals are input from the first electrical signal end of the motor to be driven and output from the second electrical signal end of the motor to be driven, thereby realizing the positive rotation work of the motor to be driven. When the motor to be driven needs to be reversely rotated, the processor 140 maintains the second non-load relay 120 to be connected with the power supply 160, the processor 140 transmits a first control signal to the first non-load relay 110, and then the first non-load relay 110 controls the first non-load relay 110 to be switched to be connected with the ground 150 according to the first control signal, after the first non-load relay 110 is switched to be connected with the ground 150, the processor 140 transmits a third control signal to the load relay 130, and then the load relay 130 is controlled, so that the second electric signal end of the motor to be driven is conducted with the second non-load relay 120, and further the motor to be driven forms a complete working loop, current signals are input from the second electric signal end of the motor to be driven and output from the first electric signal end of the motor to be driven, and the reverse operation of the motor to be driven is realized.

In the above embodiment, after the first off-load relay 110 or the second off-load relay 120 is switched to be connected, the on-load relay 130 is controlled to operate, so that when the first off-load relay 110 or the second off-load relay 120 is switched to be connected, the operating circuit of the motor to be driven is in a disconnected state, no current flows, and the no-load switching requirement of the first off-load relay 110 or the second off-load relay 120 is met. The number of small-sized high-power direct-current relays is reduced by optimizing the existing brushless high-voltage direct-current motor driving circuit, and the working direction of motor current is switched by matching 2 direct-current relays (without direct-current on-load switching capability) with a group of switching functions on the basis of only using one small-sized high-power direct-current relay. The control circuit relays are synchronously reduced, the direct-current group of conversion on-load relays are low in cost and free of magnetism, no special requirements are required for the distance between a design position and a device, advantages are provided for the cost of design boards and devices in the later stage, the workload of developers is reduced, the design cost of products is reduced, and the circuit failure rate is reduced.

In one embodiment, as in fig. 2, the first off-load relay 110 includes a first control terminal and a first selection switch 112; the first control terminal is coupled to the first output terminal of the processor 140; a first end of the first selection switch 112 is connected with a first electric signal end of the motor to be driven; the first control terminal is configured to control the second terminal of the first selection switch 112 to be connected to the power supply 160 or the ground 150 according to the received first control signal transmitted by the processor 140.

Wherein the first control signal may be a low level signal or a high level signal. The first end of the first selection switch 112 is fixedly connected to a first electrical signal end of the motor to be driven, and the second end of the first selection switch 112 can be switched to connect with the ground wire 150 or the power supply 160 according to the attraction inside the first off-load relay 110. For example, when the processor 140 transmits a low level signal to the first control terminal of the first off-load relay 110, the first off-load relay 110 may be kept in a normally-closed state, such that the second terminal of the first selection switch 112 is connected to the power supply 160, and the first electrical signal terminal of the motor to be driven is connected to the power supply 160. When the processor 140 transmits a high level signal to the first control terminal of the first off-load relay 110, the internal coil of the first off-load relay 110 is turned on, so that the second terminal of the first selection switch 112 is switched from the connection power source 160 to the connection ground 150, the first electrical signal terminal of the motor to be driven is connected to the ground 150, and the first electrical signal terminal of the motor to be driven is switched to the connection power source 160 or the ground 150 by controlling the on/off of the first off-load relay 110.

It should be noted that the power supply 160 can provide a voltage signal of 170V to the first electrical signal terminal of the motor to be driven.

In one embodiment, as in fig. 2, the high voltage dc motor drive circuit further comprises a first freewheeling diode 170; the first off-load relay 110 further includes a first power supply terminal; the cathode of the first freewheeling diode 170 is connected to the first supply terminal, and the anode of the first freewheeling diode 170 is connected to the first control terminal.

The first power supply terminal can be used for receiving a 12V voltage signal.

Specifically, based on the fact that the cathode of the first freewheeling diode 170 is connected to the first power supply terminal and the anode of the first freewheeling diode 170 is connected to the first control terminal, when the first off-load relay 110 is disconnected, the first freewheeling diode 170 may be used to discharge the back electromotive force generated after the first off-load relay 110 is disconnected, thereby protecting the rear-end driving circuit device.

In one embodiment, as in fig. 2, the second off-load relay 120 includes a second control terminal and a second selection switch 122; the second control terminal is coupled to the second output terminal of the processor 140; a first end of the second selection switch 122 is used for connecting the on-load relay 130; the second control terminal is configured to control the second terminal of the second selection switch 122 to be connected to the ground 150 or to the power supply 160 according to the received second control signal transmitted by the processor 140.

Wherein, the second forward rotation control signal may be a high level signal or a low level signal. The first end of the second selection switch 122 is fixedly connected to the on-load relay 130, and the second end of the second selection switch 122 can be switched to connect with the ground 150 or the power 160 according to the internal attraction of the second off-load relay 120. For example, when the processor 140 transmits a low signal to the second control terminal of the second off-load relay 120, the second off-load relay 120 may be kept normally closed, so that the second terminal of the second selection switch 122 is connected to the power supply 160, and the on-load relay 130 is connected to the power supply 160. If the processor 140 transmits a high level signal to the second control terminal of the second off-load relay 120, the internal coil of the second off-load relay 120 is turned on, so that the second terminal of the second selection switch 122 is switched from the connection power source 160 to the connection ground 150, and the second electrical signal terminal of the motor to be driven is connected to the ground 150, and the second electrical signal terminal of the motor to be driven is switched to the connection power source 160 or the ground 150 by controlling the on/off of the second off-load relay 120.

It should be noted that the power supply 160 can provide a voltage signal of 170V to the second electrical signal terminal of the motor to be driven.

In one embodiment, as in fig. 2, the high voltage dc motor drive circuit further comprises a second freewheeling diode 180; the second off-load relay 120 further includes a second power supply terminal; the cathode of the second freewheeling diode 180 is connected to the second supply terminal and the anode of the second freewheeling diode 180 is connected to the second control terminal.

Wherein, the second power supply terminal can be used for accessing a voltage signal of 12V.

Specifically, based on the fact that the cathode of the second freewheeling diode 180 is connected to the second power supply terminal and the anode of the second freewheeling diode 180 is connected to the second control terminal, when the second off-load relay 120 is turned off, the second freewheeling diode 180 can be used to release the back electromotive force generated after the first off-load relay 110 is turned off, thereby protecting the rear-end driving circuit device.

In one embodiment, as in fig. 2, on-load relay 130 includes a third control terminal and a third selection switch 132; the third control terminal is coupled to the third output terminal of the processor 140; a first end of the third selection switch 132 is used for connecting a second electric signal end of the motor to be driven; the third control terminal is configured to control the second terminal of the third selection switch 132 to communicate with the first terminal of the second selection switch 122 according to the received third control signal transmitted by the processor 140, so as to conduct the second electrical signal terminal of the motor to be driven and the second off-load relay 120.

Wherein the third control signal may be a high level signal. The first end of the third selection switch 132 is fixedly connected to the second electrical signal end of the motor to be driven, and the second end of the third selection switch 132 can be pulled in by the on-load relay 130 to connect the second electrical signal end of the motor to be driven and the second off-load relay 120. For example, when the motor to be driven is driven to rotate forward, the processor 140 may turn on and pull the on-load relay 130 when the high level signal is transmitted to the third control terminal of the on-load relay 130 after the second off-load relay 120 is switched to connect with the ground line 150, so that the second terminal of the third selection switch 132 is connected to the first terminal of the second connection switch, and then the second electrical signal terminal of the motor to be driven is turned on with the second off-load relay 120, so that the motor to be driven forms a complete forward rotation driving loop, and forward rotation driving of the motor to be driven is achieved. If the to-be-driven motor is driven in a reverse rotation manner, the processor 140 may switch and pull the on-load relay 130 when the high level signal is transmitted to the third control end of the on-load relay 130 after the first non-on-load relay 110 is switched and connected to the ground line 150, so that the second end of the third selection switch 132 is connected to the first end of the second connection switch, and further, the second electrical signal end of the to-be-driven motor is connected to the second non-on-load relay 120, so that the to-be-driven motor forms a complete reverse rotation driving loop, and the reverse rotation driving of the to-be-driven motor is realized.

In the above embodiments, the existing brushless high-voltage dc motor driving circuit is optimized, the number of driving control circuit devices is reduced, the number of I/O ports driven by the processor 140 is reduced, and the product design cost is reduced. The method provides convenience for later hardware design, reduces synchronous devices and reduces the circuit failure rate.

In one embodiment, as in fig. 2, the high voltage dc motor drive circuit further comprises a third freewheeling diode 190; the on-load relay 130 further includes a third power supply terminal; the cathode of the third freewheeling diode 190 is connected to the third power supply terminal, and the anode of the third freewheeling diode 190 is connected to the third control terminal.

Wherein, the third power supply terminal can be used for accessing a voltage signal of 12V.

Specifically, based on the fact that the cathode of the third freewheeling diode 190 is connected to the third power supply terminal, the anode of the third freewheeling diode 190 is connected to the third control terminal, and further after the on-load relay 130 is disconnected, the reverse electromotive force generated after the on-load relay 130 is disconnected can be discharged through the third freewheeling diode 190, so that the rear-end driving circuit device is protected.

In one embodiment, as in fig. 2, the high voltage dc motor drive circuit further includes a darlington transistor assembly 210; the input terminal of the darlington transistor assembly 210 is connected to the processor 140, and the output terminal of the darlington transistor assembly 210 is connected to the first off-load relay 110, the second off-load relay 120 and the on-load relay 130, respectively.

The darlington transistor component 210 may be, but is not limited to, a darlington transistor component 210 of the ULN2003 model, for example, the darlington transistor component 210 may include 7 darlington transistors, specifically, the darlington transistor component 210 may include 7 input terminals and 7 output terminals, where the 7 input terminals and the 7 output terminals are in one-to-one correspondence.

Specifically, based on that the first input end (such as the input end IN7, the input end IN4 and the input end IN2) of the darlington transistor component 210 is connected to the processor 140, and the output end (such as the output end OUT7, the output end OUT4 and the output end OUT2) of the darlington transistor component 210 is respectively connected to the first no-load relay 110, the second no-load relay 120 and the on-load relay 130, so that when the motor to be driven is driven IN the forward direction, a high level can be transmitted to the input end IN4 of the darlington transistor component 210 through the processor 140, the input end IN7 of the darlington transistor component 210 is maintained at a low level, and the first no-load relay 110 is maintained to be turned off, so that the first electrical signal end of the motor to be driven is connected to the power supply 160; the second off-load relay 120 is turned on so that the on-load relay 130 is connected to the ground 150. Then, after a preset time (for example, 0.5S), the processor 140 may transmit a high level to the input terminal IN2 of the darlington transistor assembly 210, so as to turn on the on-load relay 130, further turn on the second electrical signal terminal of the motor to be driven and the second off-load relay 120, and turn on the forward rotation loop of the motor to be driven, thereby implementing forward rotation driving of the motor to be driven.

In the above embodiment, the darlington transistor assembly 210 is disposed between the processor 140 and each relay (i.e., the first off-load relay 110, the second off-load relay 120, and the on-load relay 130), so as to amplify the control signal transmitted by the processor 140, and provide the amplified signal to the corresponding relay, thereby driving each relay.

In a specific embodiment, the high-voltage direct-current motor driving circuit further comprises a decoupling capacitor; the decoupling capacitor is connected between a power supply terminal of the darlington transistor assembly and a ground terminal of the darlington transistor assembly.

The decoupling capacitor can be used for providing a stable power supply, and simultaneously can reduce the noise of the element coupled to a power supply end, and indirectly can reduce the influence of the noise of the element on other elements. The decoupling capacitor is connected between a power supply end of the Darlington transistor component and a grounding end of the Darlington transistor component, and an anti-interference effect is achieved.

In one embodiment, as shown in fig. 3, a processor (e.g., a single chip microcomputer) controls three relays (i.e., a first off-load relay RL1, a second off-load relay RL2 and an on-load relay RL3) through I/O ports to realize direction control of current, wherein the I/O ports (i.e., I/O1, I/O2 and I/O3) of the three single chip microcomputers are all low level in an initial state.

Specifically, when the motor M to be driven needs to rotate forward, that is, the current direction is from pin 1 to pin 2 of the motor M to be driven, the single chip Microcomputer (MCU) I/O2 outputs a high level, pin 13 of the darlington transistor assembly U1 is pulled low, the coil of the second non-load relay RL2 is turned on, the contact of the second non-load relay RL2 is switched from the original pin 1 and pin 3 conduction to pin 1 and pin 2 conduction, at this time, since the load relay RL3 is not conducted, the circuit has no path when the second non-load relay RL2 switches, no current flows, and the requirement of the relay for non-load switching is satisfied. When the second non-load relay RL2 is conducted, the processor controls the I/O3 to output a high level, the pin 15 of the Darlington transistor component U1 is pulled down, the load relay RL3 is conducted, and the pin 1 and the pin 2 of the load relay RL3 are attracted and conducted. In this way, the power supply DC170V passes through the pin 3 of the first non-load relay RL1 and the pin 1 to reach the pin 1 of the motor M to be driven, passes through the pin 2 to reach the pin 2 of the load relay RL3 and finally reaches the pin 2 of the second non-load relay RL2 to connect with the ground wire PGND, so as to form a complete forward rotation loop of the motor.

When the motor of the motor M to be driven needs to be reversed, namely the current direction is from 2 feet to 1 foot of the motor M to be driven, the single chip Microcomputer (MCU) I/O1 outputs high level, the 10 feet of the Darlington transistor component U1 are pulled down, the coil of the first no-load relay RL1 is conducted, the contact point of the first no-load relay RL1 is changed from the original conduction of the 1 and 3 feet to the conduction of the 1 and 2 feet, at the moment, because the load relay RL3 is not conducted, the circuit has no path when the first no-load relay RL1 is switched, no current flows, and the no-load switching requirement of the relay is met. When the first no-load relay RL1 is conducted, the processor controls the I/O3 to output a high level, the pin 15 of the Darlington transistor component U1 is pulled down, the load relay RL3 is conducted, and the pin 1 and the pin 2 of the load relay RL3 are attracted and conducted. In this way, the power supply DC170V passes through the pin 3 of the second non-load relay RL2, reaches the pin 1 of the load relay RL3 through the pin 1, reaches the pin 2 of the direct current motor after the pin 2, flows to the pin 1 of the first non-load relay RL1 through the pin 1 of the motor, and finally reaches the pin 2 of the first non-load relay RL1 to be connected with the ground wire PGNG, so that a complete motor reverse loop is formed.

In the above embodiment, on the basis of only using 1 small-size high-power direct current relay (on-load relay), realize the working direction of switching motor current through the collocation use 2 direct current relays (being first on-load relay and second off-load relay) that have a set of conversion function, reduce the quantity of small-size high-power direct current relay, and with low costs, and it does not have the magnetism nature, there is not special requirement to the distance between design position and the device, optimize circuit design, reduce the software control degree of difficulty, design cloth board and device cost in the later stage provide advantages, optimize the PCB cloth board and walk the line, reduce the fault rate of circuit, reduce developer's work load.

In one embodiment, a driving circuit board of a high-voltage direct-current motor driving circuit is further provided, and the high-voltage direct-current motor driving circuit is arranged on the circuit substrate.

Wherein, the circuit substrate can be a double-layer PCB board.

Specifically, based on the high-voltage direct-current motor driving circuit arranged on the circuit substrate, the processor can transmit a first control signal to the first off-load relay, and the first off-load relay controls the first electric signal end of the motor to be driven to switch the connection ground wire or the power supply according to the received first control signal. For example, in an initial state of the first non-load relay, the first electrical signal end of the to-be-driven motor is connected to the power supply, and when the first non-load relay receives the first control signal, the first electrical signal end of the to-be-driven motor can be controlled to be switched from the power supply to the ground. The processor can also transmit a second control signal to a second non-loaded relay, and the second non-loaded relay controls a second electric signal end of the motor to be driven to switch and connect the ground wire or the power supply according to the received second control signal. For example, in the initial state of the second non-load relay, the second electrical signal end of the to-be-driven motor is connected to the power supply, and when the second non-load relay receives the second control signal, the second electrical signal end of the to-be-driven motor can be controlled to be switched from the power supply to the ground. The processor can also transmit a third control signal to the on-load relay after the first off-load relay is switched to be connected with the ground wire or after the second off-load relay is switched to be connected with the ground wire, and the on-load relay controls the connection or disconnection between the second electric signal end of the motor to be driven and the second off-load relay according to the received third control signal transmitted by the processor; for example, in the initial state of the on-load relay, the second electrical signal end of the motor to be driven and the second off-load relay are disconnected, and when the on-load relay receives the third control signal, the on-load relay can control the second electrical signal end of the motor to be driven and the second off-load relay to be connected.

Furthermore, when the motor to be driven needs to rotate forwards, the processor maintains the first non-loaded relay to be connected with the power supply, so that the first electric signal end of the motor to be driven is communicated with the power supply, the processor transmits a second control signal to the second non-load relay, the second off-load relay controls the second off-load relay to switch the ground wire according to the second control signal, the processor transmits a third control signal to the on-load relay after the second off-load relay switches the ground wire, further controlling the loaded relay to conduct the second electric signal end of the motor to be driven and the second non-loaded relay, thereby enabling the motor to be driven to form a complete working loop, realizing the input of a current signal from the first electric signal end of the motor to be driven, and the second electric signal end of the motor to be driven is output, so that the forward rotation of the motor to be driven is realized. When the motor to be driven needs to be reversely rotated, the processor maintains the second non-loaded relay to be connected with the power supply, the processor transmits a first control signal to the first non-loaded relay, the first non-loaded relay controls the first non-loaded relay to be switched and connected with the ground wire according to the first control signal, the processor transmits a third control signal to the loaded relay after the first non-loaded relay is switched and connected with the ground wire, and then the loaded relay is controlled, so that the second electric signal end of the motor to be driven is conducted with the second non-loaded relay, the motor to be driven forms a complete working loop, current signals are input from the second electric signal end of the motor to be driven and output from the first electric signal end of the motor to be driven, and the reverse rotation work of the motor to be driven is realized.

In the above embodiment, after the first non-loaded relay or the second non-loaded relay is switched to be connected, the loaded relay is controlled to operate, so that when the first non-loaded relay or the second non-loaded relay is switched to be connected, the working circuit of the motor to be driven is in a disconnected state, no current flows, and the requirement for non-loaded switching of the first non-loaded relay or the second non-loaded relay is met. The number of small-sized high-power direct-current relays is reduced by optimizing the existing brushless high-voltage direct-current motor driving circuit, and on the basis of only using one small-sized high-power direct-current relay, the working direction of motor current is switched by matching and using 2 direct-current relays (without direct-current on-load switching capability) with a group of switching functions. The control circuit relays are synchronously reduced, the direct-current group of conversion on-load relays are low in cost and non-magnetic, no special requirements are required for the distance between a design position and a device, advantages are provided for the cost of a design layout and the device, the workload of developers is reduced, the product design cost is reduced, the circuit failure rate is reduced, and the size of a circuit board is reduced.

In one example, as shown in fig. 3, the specific process of forward rotation of the motor to be driven is as follows: the circuit is initially electrified, if a motor forward rotation program is executed, a high level is output through the processor I/O2, the second non-loaded relay RL2 is conducted, the second non-loaded relay RL2 is controlled to be connected with the ground wire in a switching mode, the processor delays the preset time (such as 0.5S) after the second non-loaded relay RL2 is conducted, the high level is output through the I/O3, the loaded relay RL3 is conducted, the second electric signal end of the motor to be driven is conducted with the second non-loaded relay, a forward rotation loop of the motor to be driven is communicated, and forward rotation of the motor to be driven is achieved. When the motor to be driven needs to be stopped, low levels are respectively output through the processors I/O1, I/O2 and I/O2, and therefore the motor to be driven stops working.

The reverse rotation process of the motor to be driven comprises the following steps: the circuit is initially electrified, if a motor reversing program is executed, a high level is output through the processor I/O1, the first non-loaded relay RL1 is conducted, the first non-loaded relay RL1 is controlled to be connected with the ground wire in a switching mode, the processor delays preset time (such as 0.5S) after the first non-loaded relay RL1 is conducted, the high level is output through the I/O3, the loaded relay RL3 is conducted, further the second electric signal end of the motor to be driven is conducted with the second non-loaded relay, a reversing loop of the motor to be driven is communicated, and therefore the motor to be driven is reversed. When the motor to be driven needs to be stopped, low levels are respectively output through the processors I/O1, I/O2 and I/O2, and therefore the motor to be driven stops working.

The technical features of the above embodiments can be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the above embodiments are not described, but should be considered as the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only express several embodiments of the present application, and the description thereof is more specific and detailed, but not construed as limiting the claims. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the concept of the present application, which falls within the scope of protection of the present application. Therefore, the protection scope of the present patent shall be subject to the appended claims.

Claims

1. A high voltage dc motor drive circuit, comprising:

the first off-load relay is coupled with the processor and is configured to control a first electric signal end of the motor to be driven to switch and connect the ground wire or the power supply according to a received first control signal transmitted by the processor;

the second off-load relay is coupled with the processor and is configured to control a second electric signal end of the motor to be driven to switch between a ground wire or a power supply according to a received second control signal transmitted by the processor;

the processor is configured to maintain the first non-loaded relay connected with the power supply and control the second non-loaded relay to be switched to be connected with the ground wire if the motor to be driven needs to rotate forwards, and control the loaded relay to enable the second electrical signal end of the motor to be driven to be conducted with the second non-loaded relay after the second non-loaded relay is switched to be connected with the ground wire; the processor is further configured to maintain the second off-load relay connected to the power supply if the to-be-driven motor needs to be reversely rotated, control the first off-load relay to be switched to be connected to the ground wire, and control the on-load relay to enable the second electrical signal end of the to-be-driven motor to be conducted with the second off-load relay after the first off-load relay is switched to be connected to the ground wire.

2. The high voltage direct current motor drive circuit according to claim 1, wherein the first off-load relay comprises a first control terminal and a first selection switch; the first control end is coupled and connected with a first output end of the processor; the first end of the first selection switch is connected with the first electric signal end of the motor to be driven; the first control end is configured to control the second end of the first selection switch to be connected with a power supply or a ground wire according to the received first control signal transmitted by the processor.

3. The high voltage direct current motor drive circuit according to claim 2, further comprising a first freewheeling diode; the first off-load relay further comprises a first power supply end; the negative electrode of the first freewheeling diode is connected with the first power supply end, and the positive electrode of the first freewheeling diode is connected with the first control end.

4. The high voltage direct current motor drive circuit according to claim 2, wherein the second off-load relay comprises a second control terminal and a second selection switch; the second control end is coupled and connected with a second output end of the processor; the first end of the second selector switch is used for connecting the on-load relay; the second control terminal is configured to control the second terminal of the second selection switch to be connected with a ground line or a power supply according to the received second control signal transmitted by the processor.

5. The HVDC motor drive circuit of claim 4, further comprising a second freewheeling diode; the second off-load relay further comprises a second power supply end; and the cathode of the second freewheeling diode is connected with the second power supply end, and the anode of the second freewheeling diode is connected with the second control end.

6. The high-voltage direct current motor drive circuit according to claim 4, wherein the on-load relay comprises a third control terminal and a third selection switch; the third control end is coupled and connected with a third output end of the processor; the first end of the third selector switch is used for being connected with a second electric signal end of the motor to be driven; the third control end is configured to control the second end of the third selection switch to be communicated with the first end of the second selection switch according to the received third control signal transmitted by the processor, so that the second electric signal end of the motor to be driven is conducted with the second off-load relay.

7. The high voltage direct current motor drive circuit of claim 6 further comprising a third freewheeling diode; the on-load relay further comprises a third power supply end; and the cathode of the third freewheeling diode is connected with the third power supply end, and the anode of the third freewheeling diode is connected with the third control end.

8. The HVDC motor drive circuit of any one of claims 1 to 7, further comprising a Darlington transistor assembly; the input end of the Darlington transistor assembly is connected with the processor, and the output end of the Darlington transistor assembly is respectively connected with the first non-on-load relay, the second non-on-load relay and the on-load relay.

9. The HVDC motor drive circuit of claim 8, further comprising a decoupling capacitor; the decoupling capacitor is connected between a power supply terminal of the Darlington transistor component and a grounding terminal of the Darlington transistor component.

10. A driving circuit board of a high-voltage direct current motor driving circuit, which is characterized by comprising a circuit substrate and the high-voltage direct current motor driving circuit as claimed in any one of claims 1-9 arranged on the circuit substrate.