Disclosure of Invention
In view of the above, the present invention provides an anti-jamming circuit, an anti-jamming device, and an electrical apparatus, so as to solve the problem of low reliability and safety of the existing motor control.
In order to achieve the above object, the present invention provides an anti-interference circuit, which includes a signal input terminal, a control switch and a charging module;
the signal input end is connected with the first end of the control switch;
the first end of the control switch is also connected with a motor controller corresponding to the anti-interference circuit;
the second end of the control switch is connected with the driving end of the charging module;
the third end of the control switch and the grounding end of the charging module are respectively grounded;
the power supply end of the charging module is connected with a power supply;
after the power supply supplies power to the charging module, the charging module is charged, and the driving end of the charging module outputs a first level signal, so that after the control switch is switched on, a loop among the signal input end, the third end of the control switch and the ground is in a conducting state, and a control signal received by the signal input end directly flows into the ground;
and after the charging time of the charging module reaches the set time, the driving end of the charging module outputs a second level signal, so that after the control switch is switched off, a loop among the signal input end, the third end of the control switch and the ground is in a switched-off state, and a control signal received by the signal input end flows into the input end of the motor controller.
Further, in the above anti-jamming circuit, the charging module includes a first resistor, a second resistor, and a capacitor;
the first end of the first resistor is a power supply end of the charging module;
the connection end of the second end of the first resistor, the first end of the second resistor and the first end of the capacitor is used as the driving end of the charging module;
and the connecting end of the second resistor and the second end of the capacitor is used as the grounding end of the charging module.
Further, in the above anti-jamming circuit, the set time is determined according to a resistance value of the first resistor, an off-voltage of the control switch, a capacitance value of the capacitor, and a voltage of the power supply.
Further, in the above anti-jamming circuit, the formula for determining the set time is:
T=-Rc*ln(1-u/E);
wherein, T is the set time, R is the resistance value of the first resistor, c is the capacitance value of the capacitor, u is the turn-off voltage value of the control switch, and E is the voltage value of the power supply.
Further, in the above-described anti-tamper circuit, the first resistor is a variable resistor.
Further, in the above anti-jamming circuit, the control switch is a PNP type switch.
Further, in the above anti-jamming circuit, the PNP switch includes a PNP triode or a PNP metal-oxide-semiconductor field effect transistor.
Furthermore, the anti-jamming circuit further comprises a third resistor;
the signal input end is connected with the first end of the control switch through the third resistor.
The invention also provides an anti-interference device which is provided with the anti-interference circuit.
The invention also provides electrical equipment which comprises a main controller, a motor controller and the anti-interference device;
the main controller is connected with the signal input end of the anti-interference device;
and the first end of a control switch of the anti-interference device is connected with the motor controller.
Further, in the electrical equipment, the anti-interference device is integrated in the motor controller.
Further, in the electrical equipment, the electrical equipment is an air conditioner and/or a water heater.
After the charging module is powered on, the first level signal can be sent to the control switch to enable the control switch to be conducted, the loop among the signal input end, the third end of the control switch and the ground is in a conducting state, and the control signal received by the signal input end does not flow through the input end of the motor controller any more, so that the interference of the control signal to the motor controller at the moment of powering on is prevented, and the phenomenon of rotation or shaking caused by the fact that a controlled motor does not have a PWM pulse instruction at the moment of powering on is avoided. After the charging module finishes charging, a second level signal is sent to the control switch to enable the control switch to be disconnected, then the loops among the signal input end, the third end of the control switch and the ground are in a disconnected state, and a control signal received by the signal input end needs to flow through the input end of the motor controller, so that the motor controller can control the controlled motor. By adopting the technical scheme of the invention, the reliability and the safety of motor control can be improved.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the technical solutions of the present invention will be described in detail below. It is to be understood that the described embodiments are merely exemplary of the invention, and not restrictive of the full scope of the invention. All other embodiments, which can be derived by a person skilled in the art from the examples given herein without any inventive step, are within the scope of the present invention.
Fig. 1 is a schematic structural diagram of a first embodiment of an anti-jamming circuit according to the present invention, and as shown in fig. 1, the anti-jamming circuit according to this embodiment includes a signal input terminal 11, a control switch 12, and a charging module 13. Wherein, the signal input end 11 is connected with a first end of a control switch 12; the first end of the control switch 12 is also connected with the motor controller 2 corresponding to the anti-interference circuit; the second end of the control switch 12 is connected with the driving end of the charging module 13; the third end of the control switch 12 and the grounding end of the charging module 13 are grounded to GND respectively; the power supply terminal of the charging module 13 is connected to the power supply VCC.
In a specific implementation process, after the power supply VCC supplies power to the charging module 13, that is, after the power supply terminal of the charging module 13 is powered on, the charging module 13 starts to charge, at this time, the power supply VCC mainly charges the charging module 13, the voltage ratio flowing through the driving terminal of the charging module 13 is small and close to 0, so that the driving terminal of the charging module 13 outputs a first level signal corresponding to the small voltage, and the voltage of the signal input terminal 11 is high, so that the voltage difference between the first terminal of the control switch 12 and the second terminal of the control switch 12 reaches the conduction condition of the control switch 12, so that the control switch 12 can be turned on, so that a loop between the signal input terminal 11, the third terminal of the control switch 12 and the ground is in a conduction state, the control signal received by the signal input terminal 11 directly flows into the ground, so that at the instant of powering on of the charging module, the control signal received by the signal input end 11 can be filtered, so that the PWM port of the main controller is prevented from transmitting an interference signal to the motor controller 2, and the phenomenon that the controlled motor rotates or shakes when no PWM pulse instruction exists at the moment of switching on the power supply is avoided.
As the charging time of the charging module 13 increases, when the charging time of the charging module 13 reaches the set time, because the voltage of the charging module 13 reaches a certain value, the power supply VCC continues to supply power, and at this time, the driving end of the charging module 13 can output a higher voltage, and outputs the second level signal of higher voltage to the second terminal of the control switch 12, so that the voltage difference between the first terminal of the control switch 12 and the second terminal of the control switch 12 cannot reach the conduction condition of the control switch 12, thus, after the control switch 12 is turned off, the loop between the signal input terminal 11, the third terminal of the control switch 12 and the ground is in an off state, and at this time, the control signal received by the signal input terminal 11 flows into the input terminal of the motor controller 2, so that the motor controller 2 controls the controlled motor to ensure that the controlled motor can operate safely and reliably.
The anti-jamming circuit of this embodiment, after charging module 13 and power on, can send out first level signal to control switch 12 and make control switch 12 switch on the back, signal input end 11, the return circuit between the third end of control switch 12 and the ground is in the conducting state, the control signal that signal input end 11 received no longer flows through the input of motor controller 2, thereby prevented to go up the interference of electric instantaneous control signal to motor controller 2, avoided being controlled the motor in the moment of switching on the power, because the phenomenon of taking place rotation or shake when there is no PWM pulse instruction. After the charging time of the charging module 13 reaches the set time, a second level signal is sent to the control switch 12 to turn off the control switch 12, and then the loops between the signal input end 11, the third end of the control switch 12 and the ground are in a disconnected state, and the control signal received by the signal input end 11 needs to flow through the input end of the motor controller 2, so that the motor controller 2 controls the controlled motor. By adopting the technical scheme of the invention, the reliability and the safety of motor control can be improved.
Fig. 2 is a schematic structural diagram of a second embodiment of the anti-jamming circuit according to the present invention, and as shown in fig. 2, this embodiment further describes the technical solution of the present invention in more detail on the basis of the above embodiments.
As shown in fig. 2, in the anti-jamming circuit of this embodiment, the charging module 13 may include a first resistor R1, a second resistor R2, and a capacitor C. A first end of the first resistor R1 is a power supply end of the charging module 13, so that a first end of the first resistor R1 is connected to the power supply VCC; the connection end of the second end of the first resistor R1, the first end of the second resistor R2 and the first end of the capacitor C is used as the driving end of the charging module 13, so that the second end of the first resistor R1, the first end of the second resistor R2 and the first end of the capacitor C are all connected with the second end of the control switch 12; the connection end of the second resistor R2 and the second end of the capacitor C serves as the ground end of the charging module 13, so that the second end of the second resistor R2 and the second end of the capacitor C are both grounded.
In practical applications, the charging time (i.e., the setting time) of the charging module 13 in the present embodiment may be determined according to the resistance value of the first resistor R1, the capacitance value of the capacitor C, the turn-off voltage of the control switch 12, and the voltage of the power supply VCC. Specifically, the set time may be obtained according to equation (1).
T=-Rc*ln(1-u/E) (1)
Where T is the set time, R is the resistance of the first resistor R1, C is the capacitance of the capacitor C, u is the turn-off voltage of the control switch 12, and E is the voltage of the power supply VCC.
In one implementation, a variable resistor may be used as the first resistor R1, so that more scenarios may be used without requiring replacement of electrical components.
In this embodiment, the control switch 12 is preferably a PNP-type switch. The PNP type switch comprises a PNP type triode or a PNP type metal-oxide-semiconductor field effect transistor. Fig. 2 illustrates a PNP transistor as an example to describe the technical solution of the present invention. The first end of the control switch 12 is an emitter of the PNP triode, the second end of the control switch 12 is a base of the PNP triode, and the third end of the control switch 12 is a collector of the PNP triode. When the power supply VCC is input, the capacitor C can be charged, at the moment, the capacitor C is approximately equivalent to one section of conducting wire, so that the base electrode of the PNP type triode is connected with the ground GND, the voltage is equivalent to 0, the emitting electrode of the PNP type triode is connected with the signal input end 11, the voltage is greater than 0, the base electrode voltage is smaller than the emitter electrode voltage, the PNP type triode is conducted, at the moment, the emitting electrode of the PNP type triode and the collecting electrode are equivalent to one conducting wire, the PWM waveform is connected with the ground through the triode, and the filtering effect is. After the charging time of the capacitor C reaches the set time t, the capacitor C reaches a certain numerical value, a circuit where the capacitor C is located is equivalent to an open circuit, at the moment, the power supply VCC continues to supply power, the first resistor R1 and the second resistor R2 divide the voltage, at the moment, the driving end of the charging module 13 is equivalent to the voltage of the second resistor R2 to provide voltage for the base electrode of the PNP type triode, at the moment, the base electrode voltage of the PNP type triode is higher than the emitter electrode voltage of the PNP type triode, the PNP type triode is cut off, at the moment, the PWM waveform can only flow into the input end of the motor controller 2, so that the interference waveform is filtered within the set time t after the main controller is electrified, and the PWM waveform flows into the motor controller 2 after the set time t, and the rotation.
In practical applications, as shown in fig. 2, the anti-jamming circuit of the present embodiment further includes a third resistor R3; the signal input terminal 11 is connected to the first terminal of the control switch 12 through a third resistor R3 for current limiting using a third resistor R3.
The invention also provides an anti-interference device which is provided with the anti-interference circuit of the embodiment.
Fig. 3 is a schematic structural diagram of an electrical apparatus according to an embodiment of the present invention, and as shown in fig. 3, the electrical apparatus according to the embodiment includes a main controller 3, a motor controller 2, and the anti-jamming device 1 according to the embodiment. The main controller 3 is connected with a signal input end of the anti-interference device 1; the first end of the control switch of the anti-jamming device 1 is connected with the motor controller 2. Wherein, the electrical equipment is an air conditioner and/or a water heater.
The electrical equipment of this embodiment, through setting up anti jamming unit 1, make charging module 13 go up the electricity back, can send first level signal to control switch 12 and make control switch 12 switch on the back, signal input end 11, the return circuit between the third end of control switch 12 and the ground is in the conducting state, the control signal that signal input end 11 received no longer flows through motor controller 2's input, thereby the interference of power-on instantaneous control signal to motor controller 2 has been prevented, the controlled motor has been avoided in the moment of switch-on power, because the phenomenon of taking place rotation or shake when there is not PWM pulse instruction. After the charging time of the charging module 13 reaches the set time, a second level signal is sent to the control switch 12 to turn off the control switch 12, and then the loops between the signal input end 11, the third end of the control switch 12 and the ground are in a disconnected state, and the control signal received by the signal input end 11 needs to flow through the input end of the motor controller 2, so that the motor controller 2 controls the controlled motor. By adopting the technical scheme of the invention, the reliability and the safety of motor control can be improved.
Further, the interference rejection device 1 may be integrated in the motor controller 2.
It is understood that the same or similar parts in the above embodiments may be mutually referred to, and the same or similar parts in other embodiments may be referred to for the content which is not described in detail in some embodiments.
It should be noted that the terms "first," "second," and the like in the description of the present invention are used for descriptive purposes only and are not to be construed as indicating or implying relative importance. Further, in the description of the present invention, the meaning of "a plurality" means at least two unless otherwise specified.
Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention, and that variations, modifications, substitutions and alterations can be made to the above embodiments by those of ordinary skill in the art within the scope of the present invention.