Relay loss reduction circuit and device

Abstract

The utility model provides a relay loss reduction circuit and device which are used for driving a relay. The relay loss reduction circuit comprises a control module, a switch module and a power supply voltage stabilization module. The control module is used for outputting a first control signal in a first time period when the power supply is powered on; the switch module is used for being switched on when receiving the first control signal, so that the second end of the relay coil is grounded through the switch module; the power supply voltage stabilizing module is used for being fully charged in a second time period when the power supply is powered on, and outputting driving voltage to the first end of the relay coil at the moment when the switch module is switched on so as to drive the attraction of the relay contact; after the switch module is switched on for a period of time, maintaining voltage is output to the first end of the relay coil so as to maintain actuation of the relay contact; wherein the first time period is larger than the second time period, and the driving voltage is larger than the maintaining voltage. According to the invention, the low maintaining voltage is provided after the relay is actuated, so that the energy consumption of the relay in the working process is effectively reduced.

Description

Technical Field

[0001] The present application belongs to the field of power electronics technology, and specifically relates to a relay loss reduction circuit and device. Background Art

[0002] In engineering applications, in order to achieve higher power efficiency, relay loss reduction circuits are highly valued and widely used. This is because when the relay is working, if it is continuously in a high voltage power supply state, it will produce a large energy loss, affecting the efficiency and performance of the entire power system.

[0003] The traditional way to reduce the loss of relays is to build two power supplies. One of them provides the rated voltage of the relay, which is usually high and can generate enough electromagnetic force to ensure the relay is smoothly attracted. The other power supply is set to the relay maintenance voltage, which is about 50% of the rated voltage.

[0004] This method can reduce the loss of the relay, but it requires two voltages of different amplitudes, which greatly increases the circuit cost. At the same time, after the relay is energized, the two power supplies must be switched, which also increases the complexity of control and affects reliability. Utility Model Content

[0005] The embodiments of the present application provide a relay loss reduction circuit and device, which provide a lower maintenance voltage after the relay is energized, effectively reducing the energy consumption of the relay during operation and improving the overall efficiency of the power supply.

[0006] In a first aspect, an embodiment of the present application provides a relay loss reduction circuit for driving a relay, wherein the relay includes a relay coil and a relay contact; the relay loss reduction circuit includes: a control module, a switch module and a power supply voltage stabilization module; the input end of the control module and the first end of the power supply voltage stabilization module are both connected to a power supply, the second end of the power supply voltage stabilization module is connected to the first end of the relay coil, the output end of the control module is connected to the control end of the switch module, the first end of the switch module is connected to the second end of the relay coil, and the second end of the switch module and the third end of the power supply voltage stabilization module are both grounded; the control module is used to output a first control signal in a first time period when the power supply is powered on; the switch module is used to turn on when receiving the first control signal so that the second end of the relay coil is grounded through the switch module; the power supply voltage stabilization module is used to be fully charged in a second time period when the power supply is powered on, and at the moment when the switch module is turned on, a driving voltage is output to the first end of the relay coil to drive the contact to be attracted, and after the switch module is turned on for a period of time, a maintenance voltage is output to the first end of the relay coil to maintain the contact to be attracted; wherein, the first time period is greater than the second time period, and the driving voltage is greater than the maintenance voltage.

[0007] In some embodiments, the control module includes: a first input unit, a second input unit and an operational amplifier unit; the first end of the first input unit and the first end of the second input unit are both connected to the power supply, the second end of the first input unit is connected to the inverting input end of the operational amplifier unit, the second end of the second input unit is connected to the non-inverting input end of the operational amplifier unit, the third end of the first input unit and the third end of the second input unit are both grounded, and the output end of the operational amplifier unit is connected to the control end of the switch module; the first input unit is used for the second end of the first input unit to output a first voltage when the power supply is powered on; the second input unit is used for the second end of the second input unit to output a voltage that slowly rises to a second voltage during the first time period when the power supply is powered on; wherein the first voltage is less than the second voltage; the operational amplifier unit is used for outputting the first control signal when receiving the first voltage and the second voltage.

[0008] In some embodiments, the first input unit includes a resistor R2 and a resistor R6; a first end of the resistor R2 is connected to the power supply, a second end of the resistor R2 is connected to both a first end of the resistor R6 and an inverting input end of the operational amplifier unit, and a second end of the resistor R6 is grounded.

[0009] In some embodiments, the second input unit includes a resistor R7 and a capacitor C3; a first end of the resistor R7 is connected to the power supply, a second end of the resistor R7 is connected to both a first end of the capacitor C3 and a non-inverting input end of the operational amplifier unit, and a second end of the capacitor C3 is grounded.

[0010] In some embodiments, the operational amplifier unit includes an operational amplifier U1A and a resistor R4; the inverting input terminal of the operational amplifier U1A is connected to the second end of the first input unit, the non-inverting input terminal of the operational amplifier U1A is connected to the first end of the resistor R4 and the second end of the second input unit, and the output terminal of the operational amplifier U1A is connected to the second end of the resistor R4 and the control end of the switch module.

[0011] In some embodiments, the power supply stabilization module includes a resistor R1 and a capacitor C1; the first end of the resistor R1 is connected to the power supply, the second end of the resistor R1 is connected to the first end of the capacitor C1 and the first end of the relay coil, and the second end of the capacitor C1 is grounded.

[0012] In some embodiments, the switch module includes a resistor R3, a resistor R5 and a switch tube Q1; the first end of the resistor R3 is connected to the output end of the control module, the second end of the resistor R3 is connected to the first end of the resistor R5 and the control end of the switch tube Q1, the first end of the switch tube Q1 is connected to the second end of the relay coil, and the second end of the resistor R5 and the second end of the switch tube Q1 are both grounded.

[0013] In some embodiments, the switch module further includes a voltage regulator diode D2; a cathode of the voltage regulator diode D2 is connected to the second end of the resistor R3, and an anode of the voltage regulator diode D2 is connected to the control end of the switch tube Q1.

[0014] In some embodiments, the relay loss reduction circuit further includes a filter capacitor C2; a first end of the filter capacitor C2 is connected to the power supply, and a second end of the filter capacitor C2 is grounded.

[0015] In a second aspect, an embodiment of the present application provides a relay loss reduction device, comprising the relay loss reduction circuit as described above.

[0016] The embodiment of the present application provides a relay loss reduction circuit and device, the relay loss reduction circuit is used to drive a relay, the relay includes a relay coil and a relay contact; the relay loss reduction circuit includes: a control module, a switch module and a power supply voltage stabilization module; the input end of the control module and the first end of the power supply voltage stabilization module are both connected to a power source, the second end of the power supply voltage stabilization module is connected to the first end of the relay coil, the output end of the control module is connected to the control end of the switch module, the first end of the switch module is connected to the second end of the relay coil, the second end of the switch module and the third end of the power supply voltage stabilization module are both grounded; the control module is used The first control signal is outputted in the first time period when the power supply is powered on; the switch module is used to conduct when receiving the first control signal, so that the second end of the relay coil is grounded through the switch module; the power supply voltage stabilizing module is used to be fully charged in the second time period when the power supply is powered on, and output a driving voltage to the first end of the relay coil to drive the pull-in of the relay contact at the moment when the switch module is turned on, and output a maintenance voltage to the first end of the relay coil to maintain the pull-in of the relay contact after the switch module is turned on for a period of time; wherein, the first time period is greater than the second time period, and the driving voltage is greater than the maintenance voltage. The embodiment of the present application effectively reduces the energy consumption of the relay during operation and improves the overall efficiency of the power supply by providing a lower maintenance voltage after the relay is pulled in. At the same time, compared with the traditional solution that requires two voltages of different amplitudes, the circuit structure of this invention is relatively simple, reduces the complex power supply switching control link, and reduces the design difficulty and cost. In addition, due to the simplified circuit structure, the potential fault points are reduced, thereby improving the reliability and stability of the entire system and reducing the fault risk caused by complex control and switching. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] One or more embodiments are exemplarily described by corresponding drawings, which do not constitute limitations on the embodiments. Elements with the same reference numerals in the drawings represent similar elements, and the figures in the drawings do not constitute proportional limitations unless otherwise stated.

[0018] Figure 1 is a structural block diagram of a relay loss reduction circuit provided in an embodiment of the present application;

[0019] Figure 2 is a structural block diagram of a control module provided in an embodiment of the present application;

[0020] Figure 3 Schematic diagram of the circuit structure of a relay loss reduction circuit provided in one embodiment of the present application. DETAILED DESCRIPTION

[0021] In order to make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme in the embodiments of the present application will be described clearly and in detail in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0022] The technical features involved in the various embodiments of the present application described below do not conflict with each other and can be combined with each other.

[0023] When an element is referred to as being “connected to” another element, it can be directly connected to the other element, or one or more intervening elements may be present therebetween.

[0024] The terms "first", "second", etc. in the specification and claims of this application are used to distinguish similar objects, and are not used to describe a specific order or sequence. It should be understood that the terms used in this way can be interchangeable under appropriate circumstances, so that the embodiments of the present application can be implemented in an order other than those illustrated or described herein, and the objects distinguished by "first", "second", etc. are generally of the same type, and the number of objects is not limited. For example, the first object can be one or more.

[0025] In engineering applications, in order to achieve higher power efficiency, relay loss reduction circuits are highly valued and widely used. This is because when the relay is working, if it is continuously in a high voltage power supply state, it will produce a large energy loss, affecting the efficiency and performance of the entire power system.

[0026] The traditional way to reduce the loss of relays is to build two power supplies. One of them provides the rated voltage of the relay, which is usually high and can generate enough electromagnetic force to ensure the relay is smoothly attracted. The other power supply is set to the relay maintenance voltage, which is about 50% of the rated voltage.

[0027] When the relay starts working, the rated voltage is connected first, and the strong electromagnetic force causes the relay contacts to close quickly, achieving the pull-in action. Once the relay is successfully pulled in, a switch switches the power supply to the maintenance voltage, and this lower voltage continues to power the relay.

[0028] This solution does play a role in reducing the continuous loss of the relay. Because in the working stage after the relay is energized, it does not require as high a voltage as when it is started to maintain its closed state. The lower maintenance voltage is sufficient to maintain the normal operation of the relay, thereby reducing unnecessary energy consumption.

[0029] However, this solution is not perfect. First, to achieve two voltage supplies with different amplitudes, additional components and more complex structures are required in circuit design. For example, different transformer windings and voltage stabilization circuits may be required, which undoubtedly greatly increases the cost of the circuit. Not only does it require more money to purchase hardware components, but it also consumes more manpower and time costs in the design, debugging and production of the circuit.

[0030] Secondly, the operation of switching between two power supplies after the relay is energized requires a carefully designed control circuit and precise switching timing. This not only increases the complexity of control, but also easily leads to problems such as untimely and inaccurate switching or voltage fluctuations during the switching process. Too many control links and complex logic also affect the reliability of the entire system and increase the possibility of failure. Once a problem occurs in the switching, it may cause the relay to work abnormally and even affect the stable operation of the entire system.

[0031] In summary, the traditional relay loss reduction circuit has a certain effect in reducing losses, but there are obvious challenges in terms of cost and reliability, which has also prompted people to continuously explore and research more optimized relay loss reduction solutions.

[0032] See also Figure 1 , Figure 1 1 is a structural block diagram of a relay loss reduction circuit 10 provided in one embodiment of the present application.

[0033] The embodiment of the present application provides a relay loss reduction circuit 10, which is used to drive a relay RLY1. The relay RLY1 includes a relay coil and a relay contact.

[0034] The relay loss reduction circuit 10 includes a control module 12 , a switch module 13 and a power supply voltage stabilization module 11 .

[0035] Among them, the input end of the control module 12 and the first end of the power supply stabilizing module 11 are both connected to the power supply 20, the second end of the power supply stabilizing module 11 is connected to the first end of the relay coil, the output end of the control module 12 is connected to the control end of the switch module 13, the first end of the switch module 13 is connected to the second end of the relay coil, and the second end of the switch module 13 and the third end of the power supply stabilizing module 11 are both grounded.

[0036] like Figure 1 As shown, the end labeled 1 next to the relay RLY1 is the first end of the relay coil, and the end labeled 2 next to the relay RLY1 is the second end of the relay coil.

[0037] Specifically, the control module 12 is used to output a first control signal in the first time period when the power supply 20 is powered on. The switch module 13 is used to be turned on when receiving the first control signal, so that the second end of the relay coil is grounded through the switch module 13. The power supply voltage stabilization module 11 is used to be fully charged in the second time period when the power supply 20 is powered on, and output a driving voltage to the first end of the relay coil to drive the contact of the relay to close at the moment when the switch module 13 is turned on, and output a maintenance voltage to the first end of the relay coil to maintain the contact of the relay after the switch module 13 is turned on for a period of time. Among them, the first time period is greater than the second time period, and the driving voltage is greater than the maintenance voltage.

[0038] It should be noted that the first control signal is a high level signal or a low level signal.

[0039] The specific value of the first time period is related to the voltage of the power source 20 and the parameters of the components in the control module 12, and is not specifically limited here.

[0040] The specific value of the second time period is related to the voltage of the power source 20 and the parameters of the components in the power supply stabilizing module 11, and is not specifically limited here.

[0041] The driving voltage refers to the higher voltage output by the power supply stabilizing module 11 to the first end of the relay coil when the switch module 13 is turned on. Its function is to provide sufficient energy to drive the relay contacts to close. Since the closing of the relay contacts needs to overcome a certain resistance and inertia, a relatively high voltage is required to achieve a fast and reliable closing action.

[0042] The maintenance voltage is the voltage output by the power supply voltage stabilizing module 11 to the first end of the relay coil after the switch module 13 is turned on for a period of time. It is used to maintain the closed state of the relay contact after it is closed. Because once the contact is closed, only a small current is needed to keep it closed, so a maintenance voltage lower than the driving voltage can be used, which can reduce energy consumption and play a role in saving energy and reducing losses.

[0043] The specific values ​​of the driving voltage and holding voltage will vary according to the specifications, models and actual application scenarios of the relay. Generally speaking, the driving voltage should be higher than the rated working voltage of the relay to ensure reliable contact, while the holding voltage will be lower than the driving voltage, but still able to keep the contacts stably closed.

[0044] In this embodiment, when the power supply 20 is powered on, the power supply voltage stabilizing module 11 also starts charging, and after a period of time (i.e., the second time period), the power supply voltage stabilizing module 11 is fully charged. At the same time, when the power supply 20 is powered on, the control module 12 starts working, and within the first time period, the control module 12 outputs a first control signal. When the switch module 13 receives the first control signal output by the control module 12, the switch module 13 is turned on, so that the second end of the relay coil is grounded through the switch module 13. At the moment when the switch module 13 is turned on, since the power supply voltage stabilizing module 11 is already fully charged, it will output a higher driving voltage for the first end of the relay coil. This driving voltage is greater than the maintenance voltage and is sufficient to drive the relay contacts to close. After the switch module 13 is turned on for a period of time, the power supply voltage stabilizing module 11 outputs a maintenance voltage for the first end of the relay coil to maintain the closed state of the relay contacts.

[0045] The setting of the first time period being greater than the second time period here is to ensure that after the power supply and voltage stabilization module 11 can output sufficient driving voltage to make the relay contacts reliably attracted, the control module 12 outputs the first control signal to turn on the switch module 13. Specifically, at the initial stage of power-on of the power supply 20, the power supply and voltage stabilization module 11 needs a certain amount of time to charge to achieve a stable output voltage. If the control module 12 outputs the first control signal when the power supply and voltage stabilization module 11 is not ready, the relay may not be attracted normally. By making the first time period greater than the second time period, it can be ensured that the switch module 13 is turned on only when the power supply and voltage stabilization module 11 can provide the driving voltage, thereby ensuring that the relay works reliably.

[0046] The design of driving voltage greater than the holding voltage can not only meet the larger energy required when the relay contacts are closed, but also reduce energy consumption while maintaining the closed state, thus playing a role in reducing losses. In this way, unnecessary power loss can be reduced and the overall efficiency of the circuit can be improved while ensuring the normal operation of the relay. The working process of the entire circuit realizes effective driving and loss reduction control of the relay, and through reasonable timing and voltage control, it ensures the stable operation of the relay and reduces energy consumption.

[0047] See also Figure 2 , Figure 2 It is a structural block diagram of the control module 12 provided in one embodiment of the present application.

[0048] In some embodiments, the control module 12 includes: a first input unit 121 , a second input unit 122 , and an operational amplifier unit 123 .

[0049] Among them, the first end of the first input unit 121 and the first end of the second input unit 122 are both connected to the power supply 20, the second end of the first input unit 121 is connected to the inverting input end of the operational amplifier unit 123, the second end of the second input unit 122 is connected to the non-inverting input end of the operational amplifier unit 123, the third end of the first input unit 121 and the third end of the second input unit 122 are both grounded, and the output end of the operational amplifier unit 123 is connected to the control end of the switch module 13.

[0050] Specifically, the first input unit 121 is used to output a first voltage at the second end of the first input unit 121 when the power supply 20 is powered on. The second input unit 122 is used to output a voltage at the second end of the second input unit 122 that slowly rises to a second voltage during a first time period when the power supply 20 is powered on; wherein the first voltage is less than the second voltage. The operational amplifier unit 123 is used to output a first control signal when receiving the first voltage and the second voltage.

[0051] In this embodiment, when the power source 20 is powered on, the first input unit 121 and the second input unit 122 start working at the same time.

[0052] When the power source 20 is powered on, the second end of the first input unit 121 directly outputs a fixed first voltage.

[0053] The second input unit 122 is different. In the first time period after the power source 20 is powered on, the voltage outputted from the second end thereof gradually increases until it reaches the second voltage. Furthermore, the first voltage is lower than the second voltage.

[0054] The operational amplifier unit 123 receives the first voltage from the first input unit 121 and the second voltage from the second input unit 122. In the initial stage, since the first voltage is less than the second voltage, the operational amplifier unit 123 outputs a low level signal. As time goes by, when the output voltage of the second input unit 122 gradually rises to the second voltage, the voltage received by the operational amplifier unit 123 reaches a certain condition, thereby outputting the first control signal, that is, a high level signal.

[0055] It should be noted that the specific value of the first voltage is related to the voltage of the power supply 20 and the parameters of the components in the first output unit 121, and is not specifically limited here. The specific value of the second voltage is related to the voltage of the power supply 20 and the parameters of the components in the second output unit 122, and is not specifically limited here.

[0056] The delayed output of the control signal is achieved through the cooperation of the first input unit 121 and the second input unit 122. The first time period is set so that after the power supply 20 is powered on, the power supply voltage stabilization module 11 is given enough time to charge to ensure that it can output a stable driving voltage. When the output voltage of the second input unit 122 rises to the second voltage, it indicates that the power supply voltage stabilization module 11 is ready to provide the driving voltage. At this time, the operational amplifier unit 123 outputs the first control signal to turn on the switch module 12, so that the driving voltage output by the power supply voltage stabilization module 11 can drive the relay contacts to close.

[0057] This design can ensure that the relay is reliably closed at the right time, and after closing, the power supply voltage regulator module provides a maintenance voltage to maintain the closed state, while achieving the purpose of reducing energy loss.

[0058] See also Figure 3 , Figure 3 1 is a schematic diagram of the circuit structure of a relay loss reduction circuit 10 provided in an embodiment of the present application.

[0059] In some embodiments, the first input unit 121 includes a resistor R2 and a resistor R6, wherein a first end of the resistor R2 is connected to the power supply 20, a second end of the resistor R2 is connected to a first end of the resistor R6 and an inverting input end of the operational amplifier unit 123, and a second end of the resistor R6 is grounded.

[0060] Please also read Figure 2 and Figure 2 , wherein the first end of the first input unit 121 is Figure 3 The first end of the resistor R2, the second end of the first input unit 121 is the second end of the resistor R2, and the third end of the first input unit 121 is the second end of the resistor R6.

[0061] It should be noted that Figure 3 The voltage of the power source 20 is taken as +12 V. In some other embodiments, the voltage of the power source 20 can be set according to actual needs.

[0062] In some embodiments, the second input unit 122 includes a resistor R7 and a capacitor C3, wherein a first end of the resistor R7 is connected to the power supply 20, a second end of the resistor R7 is connected to a first end of the capacitor C3 and a non-inverting input end of the operational amplifier unit 123, and a second end of the capacitor C3 is grounded.

[0063] Please also read Figure 2 and Figure 3 , wherein the first end of the second input unit 122 is the first end of the resistor R7, the second end of the second input unit 122 is the second end of the resistor R7, and the third end of the second input unit 122 is the second end of the capacitor C3.

[0064] In some embodiments, the operational amplifier unit 123 includes an operational amplifier U1A and a resistor R4. The inverting input terminal of the operational amplifier U1A is connected to the second terminal of the first input unit 121, the non-inverting input terminal of the operational amplifier U1A is connected to the first terminal of the resistor R4 and the second terminal of the second input unit 122, and the output terminal of the operational amplifier U1A is connected to the second terminal of the resistor R4 and the control terminal of the switch module 13.

[0065] Please also read Figure 2 and Figure 3 , wherein the non-inverting input terminal of the operational amplifier unit 123 is the non-inverting input terminal of the operational amplifier U1A, the inverting input terminal of the operational amplifier unit 123 is the inverting input terminal of the operational amplifier U1A, and the output terminal of the operational amplifier unit 123 is the output terminal of the operational amplifier U1A.

[0066] In some embodiments, the power supply stabilizing module 11 includes a resistor R1 and a capacitor C1, wherein a first end of the resistor R1 is connected to the power source 20, a second end of the resistor R1 is connected to a first end of the capacitor C1 and a first end of the relay coil, and a second end of the capacitor C1 is grounded.

[0067] Please also read Figure 1 and Figure 3 , wherein the first end of the power supply stabilizing module 11 is the first end of the resistor R1, the second end of the power supply stabilizing module 11 is the second end of the resistor R1, and the third end of the power supply stabilizing module 11 is the second end of the capacitor C1.

[0068] In some embodiments, the switch module 13 includes a resistor R3, a resistor R5, and a switch tube Q1. The first end of the resistor R3 is connected to the output end of the control module 12, the second end of the resistor R3 is connected to the first end of the resistor R5 and the control end of the switch tube Q1, the first end of the switch tube Q1 is connected to the second end of the relay coil, and the second end of the resistor R5 and the second end of the switch tube Q1 are both grounded.

[0069] Please also read Figure 1 and Figure 3 , wherein the control end of the switch module 13 is the first end of the resistor R3 , the first end of the switch module 13 is the first end of the switch tube Q1 , and the second end of the switch module 13 is the second end of the switch tube Q1 .

[0070] In this embodiment, the switch tube Q1 is an NPN transistor. Specifically, the control end of the switch tube Q1 is the base of the NPN transistor, the first end of the switch tube Q1 is the collector of the NPN transistor, and the second end of the switch tube Q1 is the emitter of the NPN transistor.

[0071] In addition, the switch tube Q1 can be any controllable switch, such as an insulated gate bipolar transistor (IGBT) device, an integrated gate-commutated thyristor (IGCT) device, a gate turn-off thyristor (GTO) device, a silicon-controlled rectifier (SCR) device, a junction-gate field-effect transistor (JFET) device, a MOS-controlled thyristor (MCT) device, etc.

[0072] In some embodiments, the switch module 13 further includes a voltage regulator diode D2, wherein a cathode of the voltage regulator diode D2 is connected to the second end of the resistor R3, and an anode of the voltage regulator diode D2 is connected to the control end of the switch tube Q1.

[0073] In some embodiments, the relay loss reduction circuit 10 further includes a filter capacitor C2, wherein a first end of the filter capacitor C2 is connected to the power supply 20, and a second end of the filter capacitor C2 is grounded. Specifically, the filter capacitor C2 is used to filter the voltage of the power supply 20.

[0074] In some embodiments, the relay loss reduction circuit 10 further includes a diode D1, wherein the anode of the diode D1 is connected to the second end of the relay coil, and the cathode of the diode D1 is connected to the first end of the relay coil. Specifically, the diode D1 is a clamping diode of the relay RLY1 coil.

[0075] The following combination Figure 3 The working principle of the relay loss reduction circuit 10 provided in the embodiment of the present application is explained.

[0076] When the power is turned on, the 12V voltage begins to build up, and the operational amplifier U1A is powered and works stably. Capacitor C1 is charged through resistor R1 until it is charged to 12V. In this process, pin 2 (inverting input) of the operational amplifier U1A is instantly high-level after being divided by resistors R2 and R7. Since capacitor C3 is connected to pin 3 (non-inverting input) of the operational amplifier U1A, the voltage at the non-inverting input of the operational amplifier U1A is lower than the voltage at the inverting input. At this time, pin 1 (output) of the operational amplifier U1A outputs a low-level signal, and the switch tube Q1 is in the cut-off state.

[0077] When the 3rd pin of the operational amplifier U1A is slowly charged through the resistor R7 to a voltage higher than the inverting input terminal, the 1st pin of the operational amplifier U1A outputs a high-level signal, thereby driving the switch tube Q1 to turn on. After the switch tube Q1 is turned on, the voltages of the 1st pin (first end) and the 2nd pin (second end) of the relay RLY1 coil are 12V, and the relay RLY1 is energized. After the relay RLY1 is energized, the voltage of the relay coil is the voltage-divided value of the relay coil resistance and the resistor R1, so that during the stable operation of the relay RLY1, the actual voltage drop is the voltage-divided value of the relay coil resistance and the resistor R1.

[0078] The key to this circuit design is that the charging speed of capacitor C1 is faster than that of capacitor C3. In practical applications, this can be achieved by reducing the resistance of the charging resistor of capacitor C1 (i.e. resistor R1) and increasing the resistance of the charging resistor of capacitor C3 (i.e. resistor R7) to ensure that after capacitor C1 is fully charged with 12V, the output level of operational amplifier U1A flips from low to high, thereby driving switch tube Q1 to turn on, so that the voltage when relay RLY1 is energized is the rated voltage (maintaining voltage), and the maintaining voltage after energization is the voltage divided by the relay coil resistance and R1.

[0079] It should be noted that the charging time constant of the capacitor is τ=R*C. Where R is the resistance of the charging circuit (in ohms), C is the capacitance of the capacitor (in farads), and * represents multiplication. Therefore, the charging time constant of capacitor C1 is τ1=R1*C1. Where R1 is the resistance of resistor R1, and C1 is the capacitance of capacitor C1. The charging time constant of capacitor C3 is τ3=R7*C3. Where R7 is the resistance of resistor R7, and C3 is the capacitance of capacitor C3.

[0080] In some embodiments, τ1 needs to be set smaller than τ3, that is, the value of R1*C1 is smaller than the value of R7*C3, so that the first time period is greater than the second time period.

[0081] In some embodiments, the resistance of the resistor R2 is set to R2, and the resistance of the resistor R6 is set to R6. R2 can be set to be smaller than R6. Alternatively, twice R2 is smaller than R6. Alternatively, three times R2 is smaller than R6. Alternatively, four times R2 is smaller than R6, etc., thereby reserving sufficient time for charging the capacitor C1.

[0082] For example, when the voltage of the power supply 20 is a DC voltage of +12V, the resistance value of the resistor R1 can be set to 400 ohms, the capacitance value of the capacitor C1 can be set to 100 microfarads, the resistance value of the resistor R7 can be set to 10 kiloohms, the capacitance value of the capacitor C3 can be set to 22 microfarads, the resistance value of the resistor R2 can be set to 2 kiloohms, and the resistance value of the resistor R6 can be set to 10 kiloohms.

[0083] The embodiment of the present application provides a relay loss reduction circuit and device, the relay loss reduction circuit is used to drive a relay, the relay includes a relay coil and a relay contact; the relay loss reduction circuit includes: a control module, a switch module and a power supply voltage stabilization module; the input end of the control module and the first end of the power supply voltage stabilization module are both connected to the power supply, the second end of the power supply voltage stabilization module is connected to the first end of the relay coil, the output end of the control module is connected to the control end of the switch module, the first end of the switch module is connected to the second end of the relay coil, and the second end of the switch module and the third end of the power supply voltage stabilization module are both grounded; the control module is used to output a first control signal in a first time period when the power supply is powered on; the switch module is used to turn on when receiving the first control signal so that the second end of the relay coil is grounded through the switch module; the power supply voltage stabilization module is used to be fully charged in a second time period when the power supply is powered on, and output a driving voltage to the first end of the relay coil to drive the contact to be closed at the moment the switch module is turned on, and output a maintenance voltage to the first end of the relay coil to maintain the contact to be closed after the switch module is turned on for a period of time; wherein the first time period is greater than the second time period, and the driving voltage is greater than the maintenance voltage. The embodiment of the present application effectively reduces the energy consumption of the relay during operation and improves the overall efficiency of the power supply by providing a lower holding voltage after the relay is energized. At the same time, compared with the traditional solution that requires two voltages of different amplitudes, the circuit structure of this invention is relatively simple, which reduces the complex power switching control link and reduces the design difficulty and cost. In addition, due to the simplified circuit structure, the potential failure points are reduced, thereby improving the reliability and stability of the entire system and reducing the failure risk caused by complex control and switching.

[0084] The embodiment of the present application further provides a relay loss reduction device, comprising the relay loss reduction circuit 10 as described above.

[0085] Specifically, the relay loss reduction device is also connected to a power source and a relay to drive the relay to work.

[0086] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Under the idea of ​​the present invention, the technical features in the above embodiments or different embodiments can also be combined, and there are many other changes in different aspects of the present invention as described above, which are not provided in detail for the sake of simplicity. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments can still be modified, or some of the technical features can be replaced by equivalents. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A relay loss reduction circuit, characterized in that: Used to drive a relay, wherein the relay includes a relay coil and a relay contact; The relay loss reduction circuit comprises: a control module, a switch module and a power supply voltage stabilization module; The input end of the control module and the first end of the power supply and voltage stabilization module are both connected to a power source, the second end of the power supply and voltage stabilization module is connected to the first end of the relay coil, the output end of the control module is connected to the control end of the switch module, the first end of the switch module is connected to the second end of the relay coil, and the second end of the switch module and the third end of the power supply and voltage stabilization module are both grounded; The control module is used to output a first control signal during a first time period when the power supply is powered on; The switch module is used to be turned on when receiving the first control signal, so that the second end of the relay coil is grounded through the switch module; The power supply voltage stabilization module is used to fully charge the power supply in the second time period, and output a driving voltage to the first end of the relay coil to drive the pull-in of the relay contact at the moment when the switch module is turned on, and output a maintenance voltage to the first end of the relay coil to maintain the pull-in of the relay contact after the switch module is turned on for a period of time; Wherein, the first time period is greater than the second time period, and the driving voltage is greater than the sustaining voltage.

2. The relay loss reduction circuit according to claim 1, characterized in that: The control module includes: a first input unit, a second input unit and an operational amplifier unit; The first end of the first input unit and the first end of the second input unit are both connected to the power supply, the second end of the first input unit is connected to the inverting input end of the operational amplifier unit, the second end of the second input unit is connected to the non-inverting input end of the operational amplifier unit, the third end of the first input unit and the third end of the second input unit are both grounded, and the output end of the operational amplifier unit is connected to the control end of the switch module; The first input unit is used for outputting a first voltage at a second end of the first input unit when the power supply is powered on; The second input unit is used for slowly increasing the voltage outputted by the second end of the second input unit to a second voltage in the first time period when the power supply is powered on; wherein the first voltage is less than the second voltage; The operational amplifier unit is configured to output the first control signal when receiving the first voltage and the second voltage.

3. The relay loss reduction circuit according to claim 2, characterized in that: The first input unit includes a resistor R2 and a resistor R6; The first end of the resistor R2 is connected to the power supply, the second end of the resistor R2 is connected to both the first end of the resistor R6 and the inverting input end of the operational amplifier unit, and the second end of the resistor R6 is grounded.

4. The relay loss reduction circuit according to claim 2, characterized in that: The second input unit includes a resistor R7 and a capacitor C3; The first end of the resistor R7 is connected to the power supply, the second end of the resistor R7 is connected to both the first end of the capacitor C3 and the non-inverting input end of the operational amplifier unit, and the second end of the capacitor C3 is grounded.

5. The relay loss reduction circuit according to claim 2, characterized in that: The operational amplifier unit includes an operational amplifier U1A and a resistor R4; The inverting input terminal of the operational amplifier U1A is connected to the second end of the first input unit, the non-inverting input terminal of the operational amplifier U1A is connected to both the first end of the resistor R4 and the second end of the second input unit, and the output terminal of the operational amplifier U1A is connected to both the second end of the resistor R4 and the control terminal of the switch module.

6. The relay loss reduction circuit according to claim 1, characterized in that: The power supply voltage stabilization module includes a resistor R1 and a capacitor C1; The first end of the resistor R1 is connected to the power supply, the second end of the resistor R1 is connected to both the first end of the capacitor C1 and the first end of the relay coil, and the second end of the capacitor C1 is grounded.

7. The relay loss reduction circuit according to claim 1, characterized in that: The switch module includes a resistor R3, a resistor R5 and a switch tube Q1; The first end of the resistor R3 is connected to the output end of the control module, the second end of the resistor R3 is connected to the first end of the resistor R5 and the control end of the switch tube Q1, the first end of the switch tube Q1 is connected to the second end of the relay coil, and the second end of the resistor R5 and the second end of the switch tube Q1 are both grounded.

8. The relay loss reduction circuit according to claim 7, characterized in that: The switch module also includes a voltage stabilizing diode D2; The cathode of the voltage stabilizing diode D2 is connected to the second end of the resistor R3 , and the anode of the voltage stabilizing diode D2 is connected to the control end of the switch tube Q1 .

9. The relay loss reduction circuit according to any one of claims 1 to 8, characterized in that: The relay loss reduction circuit also includes a filter capacitor C2; A first end of the filter capacitor C2 is connected to the power supply, and a second end of the filter capacitor C2 is grounded.

10. A relay loss reduction device, characterized in that: It comprises the relay loss reduction circuit as described in any one of claims 1 to 9.

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