Relay adhesion detection circuit with low cost and high reliability

Abstract

The utility model relates to the technical field of circuit safety, in particular to a low-cost high-reliability relay adhesion detection circuit, which comprises a relay S1 contact and a relay S2 contact which are used for controlling the on-off of an optical coupler OP1, a resistor R2 and a resistor R1 are electrically connected onto a pin 1 of the optical coupler OP1, the resistor R2 is electrically connected with the relay S1 contact, and the resistor R1 is electrically connected with the relay S2 contact; a pin 2 of the optocoupler OP1 is electrically connected with a resistor R3 and a resistor R4, the resistor R3 is electrically connected with a contact of the relay S1, and the resistor R4 is electrically connected with a contact of the relay S2. According to the utility model, the relay S1 contact, the relay S2 contact, the resistor R2, the resistor R1, the resistor R3 and the resistor R4 are used and are electrically connected with the optical coupler OP1 at the same time, the positions and the number of the adhesion contacts can be accurately judged through the change of the optical coupler OP1, the production cost can be effectively reduced, the failure rate can be reduced, the batch application effect of the electric vehicle charging pile is good, and the product quality is improved. And the method has a relatively wide application prospect.

Description

TECHNICAL FIELD

[0001] The utility model relates to a relay sticking detection circuit, especially relates to a low cost high reliability relay sticking detection circuit belongs to circuit safety technical field. BACKGROUND

[0002] Electric vehicles use electric power as power source, do not produce tail gas emission, therefore do not release carbon monoxide, carbon dioxide, nitrogen oxides and other harmful gases, help to improve air quality, reduce the risk of disease caused by breathing polluted air, the operation process of electric vehicles does not produce carbon emission, is the important tool for reducing global greenhouse gas emissions.

[0003] Among them, the battery system is the core component of electric vehicles, and the high-voltage main circuit relay of the electric vehicle controls the charging and discharging of the battery system. The reliable operation of the relay is directly related to the safety of the electric vehicle. The contact sticking caused by the contact spark of the large current relay in use may cause the contact to be unable to be separated, and the control to be lost. In severe cases, it may cause safety accidents. The existing similar technology circuit is complex, and has no advantages in reliability and cost, resulting in a high failure rate.

[0004] Therefore, it is urgent to improve the detection circuit of the relay sticking to solve the above problems. CONTENT OF THE UTILITY MODEL

[0005] The utility model aims at providing a low cost high reliability relay sticking detection circuit, and the circuit uses relay S1 contact, relay S2 contact, resistance R2, resistance R1, resistance R3 and resistance R4 several discrete elements, and is electrically connected with optocoupler OP1 at the same time. The change of the optocoupler OP1 can accurately judge the position and number of the sticking contact, effectively reduce the production cost, reduce the failure rate, and has good application effect in the batch application of electric vehicle charging piles, and has a wide application prospect.

[0006] In order to achieve the above purpose, the main technical scheme of the utility model comprises:

[0007] A low cost high reliability relay sticking detection circuit, comprising relay S1 contact and relay S2 contact for controlling the on-off of optocoupler OP1, resistance R2 and resistance R1 are electrically connected to the pin 1 of the optocoupler OP1, the resistance R2 is electrically connected with the relay S1 contact, and the resistance R1 is electrically connected with the relay S2 contact.

[0008] Resistance R3 and resistance R4 are electrically connected to the pin 2 of the optocoupler OP1, the resistance R3 is electrically connected with the relay S1 contact, and the resistance R4 is electrically connected with the relay S2 contact.

[0009] Preferably, the output end of the resistor R2 is connected with a diode D2, the model of the diode D2 is IN5399, and the output end of the diode D2 is electrically connected with the optocoupler OP1.

[0010] The input end of the resistor R4 is electrically connected with a diode D3, and the diode D3 is electrically connected with the optocoupler OP1.

[0011] After the contact of the relay S2 is closed, the resistor R2, the diode D2, the optocoupler OP1, the diode D3 and the resistor R4 form a detection loop of the contact of the relay S2.

[0012] Preferably, the output end of the resistor R1 is connected with a diode D1, and the output end of the diode D1 is electrically connected with the pin 1 of the optocoupler OP1.

[0013] The input end of the resistor R3 is electrically connected with a diode D4, and the diode D4 is electrically connected with the pin 2 of the optocoupler OP1.

[0014] After the contact of the relay S1 is closed, the resistor R1, the diode D1, the optocoupler OP1, the diode D4 and the resistor R3 form a detection loop of the contact of the relay S1.

[0015] Preferably, the two ends of the contact of the relay S1 are input with an alternating current live wire L, and the detection current of the alternating current live wire L is 1.8mA.

[0016] Preferably, the two ends of the contact of the relay S2 are input with an alternating current neutral wire N, and the detection current of the alternating current neutral wire N is 1.4mA.

[0017] Preferably, the pin 4 of the optocoupler OP1 is connected with a +3.3V voltage, and the pin 3 of the optocoupler OP1 is electrically connected with a state feedback circuit.

[0018] The utility model at least has following beneficial effects:

[0019] 1, this circuit uses relay S1 contact, relay S2 contact, resistor R2, resistor R1, resistor R3 and resistor R4 several discrete components, simultaneously with optocoupler OP1 electric connection, through the change of optocoupler OP1 can accurately judge out that the position of sticking contact and sticking contact quantity, can effectively reduce production cost, reduce failure rate, in electric vehicle charging pile batch application effect is good, has the relatively broad application prospect.

[0020] 2, in relay S2 contact closed, the current through resistance R2, diode D2, optocoupler OP1, diode D3, resistance R4 and relay S2 contact in turn, through the brightness of optocoupler OP1 change can detect whether the contact relay S2 place whether occurs stickiness, the flexibility of use and the range of use further promotion, in relay S1 contact closed, the current through resistance R1, diode D1, optocoupler OP1, diode D4, resistance R3 and relay S1 contact in turn, through the brightness of optocoupler OP1 change can detect whether the contact relay S1 place whether occurs stickiness, if the relay S1 contact and relay S2 contact closed at the same time, then will form two loop at the same time, simultaneously to multiple detection, judge the stickiness contact position, greatly improve the range of use and flexibility. BRIEF DESCRIPTION OF DRAWINGS

[0021] The accompanying drawings, which are included to provide a further understanding of the application and are incorporated in and constitute a part of this application, will be

[0022] Figure 1 Structure diagram of the utility model Figure 1 ;

[0023] Figure 2 Structure diagram of the utility model Figure 2 ;

[0024] Figure 3 Structure diagram of the utility model Figure 3 . DETAILED DESCRIPTION

[0025] The embodiments of the present application will be described in detail below with reference to the drawings and embodiments, so that the realization process of how to apply technical means to solve technical problems and achieve technical effects of the present application can be fully understood and implemented.

[0026] As Figures 1-3As shown, the low-cost and high-reliability relay sticking detection circuit provided by the embodiment includes a relay S1 contact and a relay S2 contact for controlling the on-off of the optocoupler OP1, the pin 1 of the optocoupler OP1 is electrically connected with a resistor R2 and a resistor R1, the resistor R2 is electrically connected with the relay S1 contact, the resistor R1 is electrically connected with the relay S2 contact, the pin 2 of the optocoupler OP1 is electrically connected with a resistor R3 and a resistor R4, the resistor R3 is electrically connected with the relay S1 contact, and the resistor R4 is electrically connected with the relay S2 contact. The circuit uses the relay S1 contact, the relay S2 contact, the resistor R2, the resistor R1, the resistor R3 and the resistor R4, which are electrically connected with the optocoupler OP1, and the change of the optocoupler OP1 can accurately determine the sticking contact position and the number of sticking contacts, which can effectively reduce the production cost and the failure rate, and has a good application effect in the batch application of the electric vehicle charging pile and a wide application prospect.

[0027] The output end of the resistor R2 is connected with a diode D2, the model of the diode D2 is IN5399, the output end of the diode D2 is electrically connected with the optocoupler OP1, the input end of the resistor R4 is electrically connected with a diode D3, the diode D3 is electrically connected with the optocoupler OP1, and the diode can convert alternating current AC into direct current DC. Specifically, when the positive half cycle of the alternating current passes through the diode, the diode is turned on, and the current can pass through; when the negative half cycle of the alternating current comes, the diode is cut off, and the current is blocked. In this way, the current after passing through the diode only has a positive direct current component, has a unidirectional conductivity, improves the safety of the circuit, and is connected in series with the resistor to stabilize the voltage in the circuit, prevent the voltage fluctuation from being too large, and improve the safety and stability of the circuit.

[0028] After the relay S2 contact is closed, the resistor R2, the diode D2, the optocoupler OP1, the diode D3 and the resistor R4 form a detection circuit of the relay S2 contact. After the relay S2 contact is closed, the current passes through the resistor R2, the diode D2, the optocoupler OP1, the diode D3, the resistor R4 and the relay S2 contact in sequence, and the change of the brightness of the optocoupler OP1 can detect whether the sticking occurs at the relay S2 contact, and the flexibility and the range of use are further improved.

[0029] Meanwhile, the output end of the resistor R1 is connected with the diode D1, the output end of the diode D1 is electrically connected with the pin 1 of the optocoupler OPl, the input end of the resistor R3 is electrically connected with the diode D4, the diode D4 is electrically connected with the pin 2 of the optocoupler OPl, after the relay S1 contact is closed, the resistor R1, the diode D1, the optocoupler OPl, the diode D4 and the resistor R3 form a detection loop of the relay S1 contact, after the relay S1 contact is closed, the current passes through the resistor R1, the diode D1, the optocoupler OPl, the diode D4, the resistor R3 and the relay S1 contact in turn, and the change of the brightness of the optocoupler OPl can detect whether the sticking occurs at the relay S1 contact;

[0030] Of course, if the relay S1 contact and the relay S2 contact are closed at the same time, two loops are formed at the same time, and multiple places are detected at the same time, so that the position of the sticking contact can be judged, and the range and flexibility of use are greatly improved.

[0031] Further, as shown in Figure 3 , the two ends of the relay S1 contact input the alternating current fire line L, and the detection current of the alternating current fire line L is 1.8 mA, the two ends of the relay S2 contact input the alternating current zero line N, and the detection current of the alternating current zero line N is 1.4 mA, the detection current of the optocoupler OPl is 1.8 mA, and the detection current of the alternating current zero line N is 1.4 mA, which ensures the safety of the circuit and improves the service life of the optocoupler OPl.

[0032] Further, as shown in Figure 3 , the pin 4 of the optocoupler OPl is connected with +3.3V voltage for supplying power to the optocoupler OPl, and the pin 3 of the optocoupler OPl is electrically connected with a state feedback circuit, the state feedback circuit can reduce oscillation and improve the stability and response speed of the system by combining positive feedback and negative feedback.

[0033] As shown in Figures 1-3 , the principle of the low-cost and high-reliability relay sticking detection circuit provided by the embodiment is as follows:

[0034] The circuit uses the relay S1 contact, the relay S2 contact, the resistor R2, the resistor R1, the resistor R3 and the resistor R4, which are connected with the optocoupler OPl, and the change of the optocoupler OPl can accurately judge the position and the number of the sticking contacts, effectively reduce the production cost and the failure rate, and has a good effect in the batch application of the electric vehicle charging pile and a wide application prospect.

[0035] The diode can convert alternating current (AC) into direct current (DC). Specifically, when the positive half cycle of the alternating current passes through the diode, the diode is turned on, and the current can pass through; when the negative half cycle of the alternating current comes, the diode is turned off, and the current is blocked. In this way, the current after passing through the diode only has a positive direct current component, has a unidirectional conductivity, improves the safety of the circuit, and can stabilize the voltage in the circuit when connected in series with the resistor, prevents the voltage from fluctuating too much, and improves the safety and stability of the circuit.

[0036] After the relay S2 contact is closed, the resistance R2, the diode D2, the optocoupler OP1, the diode D3, and the resistance R4 form a detection loop of the relay S2 contact. After the relay S2 contact is closed, the current passes through the resistance R2, the diode D2, the optocoupler OP1, the diode D3, the resistance R4, and the relay S2 contact in turn. The brightness change of the optocoupler OP1 can detect whether the relay S2 contact is stuck, and the flexibility and range of use are further improved.

[0037] After the relay S1 contact is closed, the current passes through the resistance R1, the diode D1, the optocoupler OP1, the diode D4, the resistance R3, and the relay S1 contact in turn. The brightness change of the optocoupler OP1 can detect whether the relay S1 contact is stuck.

[0038] Of course, if the relay S1 contact and the relay S2 contact are closed at the same time, two loops will be formed at the same time, and multiple places will be detected at the same time to determine the position of the stuck contact, greatly improving the range and flexibility of use.

[0039] As some terms are used in the description and claims, those skilled in the art should understand that the same components can be referred to by different names by hardware manufacturers. The description and claims of the present application do not distinguish components by name, but by the difference in function. As mentioned throughout the description and claims, "comprising" is an open term, which should be interpreted as "comprising but not limited to". "Approximately" means within an acceptable error range, and those skilled in the art can solve technical problems within a certain error range and basically achieve the technical effect.

[0040] It should be noted that the terms "include", "contain" or any other variant thereof are intended to cover non-exclusive inclusion, so that the goods or systems including a series of elements not only include those elements, but also include other elements not explicitly listed, or include elements inherent to such goods or systems. Without more limitations, the element defined by the statement "including a" does not exclude the presence of another identical element in the goods or system including the element.

[0041] The above description shows and describes several preferred embodiments of the present application, but as previously described, it should be understood that the present application is not limited to the forms disclosed herein, and should not be considered as excluding other embodiments, but can be used in various other combinations, modifications and environments, and can be modified within the scope of the application conceived herein, by the above teachings or related art or knowledge. Any modification and change made by those skilled in the art without departing from the spirit and scope of the present application shall be within the protection scope of the claims of the present application.

Claims

1. A low cost high reliable relay stick detection circuit comprising a relay S1 contact and a relay S2 contact for controlling the on-off of an optocoupler OP1, characterized in that, The pin 1 of the photo-coupler OP1 is electrically connected with a resistor R2 and a resistor R1, the resistor R2 is electrically connected with the relay S1 contact, and the resistor R1 is electrically connected with the relay S2 contact; The pin 2 of the photo-coupler OP1 is electrically connected with a resistor R3 and a resistor R4, the resistor R3 is electrically connected with the relay S1 contact, and the resistor R4 is electrically connected with the relay S2 contact.

2. The low cost and high reliable sticking detection circuit for a relay according to claim 1, characterized in that: The output end of the resistor R2 is connected with a diode D2, the model of the diode D2 is IN5399, and the output end of the diode D2 is electrically connected with the photo-coupler OP1; The input end of the resistor R4 is electrically connected with a diode D3, and the diode D3 is electrically connected with the photo-coupler OP1; After the relay S2 contact is closed, the resistor R2, the diode D2, the photo-coupler OP1, the diode D3 and the resistor R4 form a detection loop of the relay S2 contact.

3. The low cost high reliable relay sticking detection circuit according to claim 1, characterized in that: The output end of the resistor R1 is connected with a diode D1, and the output end of the diode D1 is electrically connected with the pin 1 of the photo-coupler OP1; The input end of the resistor R3 is electrically connected with a diode D4, and the diode D4 is electrically connected with the pin 2 of the photo-coupler OP1; After the relay S1 contact is closed, the resistor R1, the diode D1, the photo-coupler OP1, the diode D4 and the resistor R3 form a detection loop of the relay S1 contact.

4. The low cost and high reliable sticking detection circuit for a relay according to claim 1, characterized in that: The both ends of the relay S1 contact input an AC live wire L, and the detection current of the AC live wire L is 1.8 mA.

5. The low cost high reliable relay sticking detection circuit according to claim 1, characterized in that: The both ends of the relay S2 contact input an AC neutral wire N, and the detection current of the AC neutral wire N is 1.4 mA.

6. The low cost high reliable relay sticking detection circuit according to claim 1, characterized in that: The pin 4 of the photo-coupler OP1 is connected with +3.3V voltage, and the pin 3 of the photo-coupler OP1 is electrically connected with a state feedback circuit.

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