AC / DC electronic relay

Abstract

An AC / DC universal electronic relay belongs to the technical field of relays. The AC / DC universal electronic relay comprises a power input module, a trigger signal input end of the power input module, and a trigger signal being an AC signal or a DC signal. The AC / DC universal electronic relay is characterized in that: a normally open contact driving module and a normally closed contact driving module are connected to the output end of the power input module, the output end of the normally open contact driving module is connected to the input end of a normally open contact; an internal power supply is arranged, the internal power supply is connected to a normally closed contact, the output end of the normally closed contact driving module is connected to the internal power supply, the normally open contact and the normally closed contact are connected to a DC loop or an AC loop, and the output end of the normally closed contact driving module is connected to a loop between the internal power supply and the normally closed contact. In the AC / DC universal electronic relay, a DC or AC driving signal can be used to drive a DC or AC type load, and the normally open contact and the normally closed contact are arranged at the same time, so that the applicability of the electronic relay is greatly improved.

Description

Technical Field

[0001] An AC / DC universal electronic relay, belonging to the field of relay technology. Background Technology

[0002] Intermediate relays are commonly used electrical components in industrial settings. Their main function is to increase the number and capacity of contacts in relay protection and automatic control systems, and to transmit intermediate signals in control circuits. In existing technology, intermediate relays are generally of a conventional mechanical structure, mainly composed of a fixed iron core, a moving iron core, a spring, moving contacts, stationary contacts, a coil, terminals, and a housing. Their main working principle is as follows: when a voltage equal to or greater than the operating voltage is applied to the relay coil, the armature is attracted to the iron core by electromagnetic force. The contact piece, pushed by the top plate of the armature, connects, disconnects, or switches the controlled circuit. When the relay coil is de-energized or the voltage drops below the operating voltage, the armature returns to its original position under the action of the contact piece. In existing technology, mechanical intermediate relays are directly plugged into a conventional intermediate relay base. Field personnel connect the intermediate relay to the control circuit by wiring from the intermediate relay base according to the pin definitions of the mechanical intermediate relay.

[0003] Because existing intermediate relays primarily rely on mechanical structures for operation, they suffer from power losses during use. Furthermore, the coil generates noise during operation, which intensifies when the armature is contaminated. Under high load currents, the contacts are prone to burning out, preventing timely release. When the main contacts release under load, arcing is likely to occur, and mechanical intermediate relays have a shorter lifespan.

[0004] With the continuous development of electronic technology, especially thyristors, electronic relays have emerged on the market. Their principle is to utilize the switching characteristics of electronic components (such as switching transistors, triacs, and other semiconductor devices) to achieve contactless and spark-free connection and disconnection of circuits, thus functioning similarly to an "electronic switch." However, existing electronic relays generally have the following drawbacks: 1. Currently, most electronic relays on the market have only one (or one set) normally open contact. That is, when the input voltage reaches the trigger condition, the output switch changes from the on state to the closed state, making them unusable in situations requiring normally closed contacts. Furthermore, existing electronic relays are large in size because they need to carry large currents, and even when normally closed contacts are not required, they cannot replace conventional mechanical intermediate relays.

[0005] Among the currently disclosed existing technologies, several technical solutions have been proposed for implementing normally closed contacts in electronic relays. The currently available technical solutions for implementing normally closed contacts in electronic relays and their respective drawbacks are as follows: (1) Scheme 1. In the prior art, one of the schemes for realizing normally closed contacts in electronic relays is to use a thyristor as an electronic switch to realize normally closed contacts. This normally closed contact technical scheme has the following defects: 1) In the current scheme, the power supply (load power supply) at the output end is generally used to drive the thyristor. Since the action of the thyristor requires a certain amount of trigger current, when the voltage of the load power supply is small, it is impossible to control the thyristor to work as expected, resulting in the failure of the normally closed contact. 2) Since the thyristor is a semi-controlled device, when using the normally closed contact formed by the thyristor, the thyristor can only be driven to open when a control signal is input at the output end of the relay. (3) The thyristor itself has a voltage drop, so in situations where the voltage requirement is relatively precise, the normally closed contact realized by the thyristor is difficult to meet the requirements.

[0006] (2) Scheme 2: In the prior art, besides using thyristors as electronic switches to realize normally closed contacts, there is also a technical solution of using transistors as electronic switches to realize normally closed contacts. When using transistors to realize normally closed contacts, there are the following drawbacks: 1) Similar to thyristors, transistors themselves have voltage drops, making them difficult to apply to applications requiring precise voltage. 2) Using transistors as electronic switches to realize normally closed contacts can only meet the requirements of DC loads and cannot meet the requirements of AC loads.

[0007] 2. Existing electronic relay products are divided into DC and AC types based on the power supply type of the load. For example, when the load is AC, an AC electronic relay is required. Therefore, both the trigger signal of the electronic relay and the power supply in the load's power supply circuit must be AC. If the trigger signal of the electronic relay and the power supply of the load are DC, it cannot be used properly. The same applies to DC-type "electronic switches." Therefore, existing electronic relays have poor applicability. Once the load type changes, the electronic relay itself and even the driving power supply need to be changed accordingly, greatly increasing the difficulty of system modification and causing extreme inconvenience to industrial applications. This also significantly limits the development of electronic relays.

[0008] Currently, there are also technical solutions on the market that can simultaneously meet AC and DC signal requirements at the input and output ends, such as the technical solution disclosed in the patent application No. 201811575885.2, entitled "A Universal AC / DC Direct-Plug-in Normally Open Electronic Intermediate Relay". The technical solution disclosed in this patent application also includes the following defects: (1) In this technical solution, only normally open contacts are provided, and normally closed contacts cannot be achieved. (2) In this technical solution, a high-frequency transformer is required to generate an oscillation signal in conjunction with the corresponding circuit. Although the final product of the technical solution disclosed in this patent can be the same size as some mechanical relays on the market so that it can be directly installed on the corresponding relay socket, the large size of the high-frequency transformer fundamentally limits the size of the final product of this solution. It cannot be the same size as the smaller conventional relays on the market, and its applicability is limited.

[0009] In summary, the urgent problem to be solved in this field is to develop an electronic relay that can be used with both AC and DC at both the input and output ends, has normally closed and normally open contacts, and is compatible with mechanical relays on the market. Summary of the Invention

[0010] The technical problem to be solved by the present invention is to overcome the shortcomings of the prior art and provide an AC / DC universal electronic relay that can realize arbitrary driving of DC or AC type loads by DC or AC drive signals, and is equipped with normally open contacts and normally closed contacts, which greatly improves the applicability of the electronic relay.

[0011] The technical solution adopted by the present invention to solve its technical problem is: the AC / DC universal electronic relay includes a power input module, a trigger signal is connected to the input terminal of the power input module, and the trigger signal is an AC signal or a DC signal. The feature is that: it is provided with normally open contacts and normally closed contacts, the output terminal of the normally open contacts is connected to a DC circuit or an AC circuit, and the output terminal of the normally closed contacts is connected to a DC circuit or an AC circuit. A normally open contact driver module and a normally closed contact driver module are connected to the output terminal of the power input module. The output terminal of the normally open contact driver module is connected to the input terminal of the normally open contact. An internal power supply is provided to drive the normally closed contact to operate. The internal power supply is connected to the input terminal of the normally closed contact. The output terminal of the normally closed contact driver module is connected to the connection circuit between the internal power supply and the normally closed contact.

[0012] Preferably, the normally open contact driving module uses a photovoltaic optocoupler, and the output terminal of the photovoltaic optocoupler is connected to the input terminal of the normally open contact.

[0013] Preferably, the normally closed contact drive module includes a photovoltaic optocoupler, a normally open optocoupler, and a normally closed optocoupler. The input terminals of the photovoltaic optocoupler, the normally open optocoupler, and the normally closed optocoupler are connected in sequence, and the output terminal of the normally open optocoupler is connected in the circuit between the built-in power supply and the normally closed contact input terminal.

[0014] Preferably, the normally open contact includes two MOSFETs connected in series. The gates of the two MOSFETs are connected to the positive output of the photovoltaic optocoupler, the sources of the two MOSFETs are connected to the negative output of the photovoltaic optocoupler, and the drains of the two MOSFETs are the terminals of the normally open contact.

[0015] The normally closed contact includes two MOSFETs connected in series. The gates of the two MOSFETs are connected to the positive output of the built-in power supply through the output terminal of the normally open optocoupler, and the sources of the two MOSFETs are connected to the negative output of the built-in power supply. The drains of the two MOSFETs are the terminals of the normally closed contact.

[0016] Preferably, the positive output terminal of the photovoltaic optocoupler is connected in series with a diode and then connected to the positive terminal of the built-in power supply, and the negative terminal of the built-in power supply is connected to the negative output terminal of the photovoltaic optocoupler.

[0017] Preferably, a bidirectional transient voltage suppressor diode is connected in parallel across the output terminals of the normally open contact, and a bidirectional transient voltage suppressor diode is connected in parallel across the output terminals of the normally closed contact.

[0018] Preferably, the power input module is a rectifier bridge circuit.

[0019] Compared with the prior art, the beneficial effects of this invention are: This AC / DC universal electronic relay can drive any DC or AC type load with DC or AC drive signals, and is equipped with normally open and normally closed contacts, which greatly improves the applicability of the electronic relay.

[0020] By connecting a bidirectional transient voltage suppressor diode in parallel across the normally open and normally closed contacts, the reverse peak voltage generated by the inductive load at the moment of disconnection can be absorbed, thus preventing the MOSFET from breaking down.

[0021] A fast recovery diode is connected in parallel between the gate and drain of the two normally open contact MOSFETs and the two normally closed contact MOSFETs, which effectively prevents the MOSFETs from being electrostatically damaged.

[0022] Because the manufacturing process dictates the presence of junction capacitance in MOSFETs, a single MOSFET can only operate in unidirectional conduction. To achieve versatility for both AC and DC loads, two MOSFETs are connected in series and parallel, with the load driven by parasitic diodes within the MOSFETs. This allows both normally open and normally closed contacts to drive either DC or AC loads. Attached Figure Description

[0023] Figure 1 This is a block diagram of an AC / DC universal electronic relay.

[0024] Figure 2 The circuit diagram of Example 1 is for an AC / DC universal electronic relay.

[0025] Figures 3-5 The circuit diagram of Example 2 is for an AC / DC universal electronic relay. Detailed Implementation

[0026] Figures 1-2 This is the preferred embodiment of the present invention, which is described below in conjunction with the accompanying drawings. Figures 1-5 The present invention will be further described below.

[0027] Example 1: like Figure 1 As shown, an AC / DC universal electronic relay (hereinafter referred to as the electronic relay) includes a power input module. The power input module is used to input a trigger signal to drive the electronic relay. The trigger signal can be a DC signal or an AC signal. The output terminal of the power input module is connected to the input terminal of the normally open contact drive module and the input terminal of the normally closed contact drive module, respectively. The output terminal of the normally open contact drive module is connected to the input terminal of the normally open contact. The output terminal of the normally open contact is the wiring terminal of the normally open contact in the electronic relay. The normally open contact can be connected to a DC circuit or an AC circuit.

[0028] This electronic relay is equipped with a built-in power supply. The output terminal of the built-in power supply is connected to the input terminal of the normally closed contact. The output terminal of the normally closed contact drive module is also connected to the input terminal of the built-in power supply to charge it. The output terminal of the normally closed contact drive module is also connected to the connection circuit between the built-in power supply and the normally closed contact, which is used to connect or disconnect the power supply circuit between the built-in power supply and the normally closed contact to realize the operation of the normally closed contact. The output terminal of the normally closed contact is the wiring terminal of the normally closed contact in this electronic relay. The normally closed contact can be connected to a DC circuit or an AC circuit.

[0029] like Figure 2As shown, the electronic relay of this application includes integrated modules U1 to U5, wherein integrated module U1 is a commercially available rectifier bridge module. One end of the input signal is connected in series with a resistor R1, which serves as a current limiter, and is connected to one of the input terminals of integrated module U1. The other end of the input signal is connected to the other input terminal of integrated module U1. When the input signal (trigger signal) is an AC signal, the AC power is rectified into DC power by the rectifier bridge module, and the rectified DC power signal is output through the positive and negative terminals of the integrated module U1, respectively. When the input signal (trigger signal) is a DC signal, regardless of whether the positive and negative terminals of the DC trigger signal are connected to the input terminals of integrated module U1, the DC signal output by the rectifier bridge is output through the positive and negative terminals of the integrated module U1, respectively, under the action of the rectifier bridge.

[0030] Integrated modules U2 to U4 are all optocoupler modules. Among them, integrated modules U2 to U3 are implemented using commercially available photovoltaic optocouplers, such as optocoupler chips with models TLP3905 and AQY1121. The characteristic of photovoltaic optocouplers is that when an input signal is applied to their input terminal, their output terminal can output a corresponding DC signal. Integrated chip U4 is implemented using commercially available normally closed optocouplers, such as chips with models AQY414 and AQY412. When there is no input signal at its input terminal, its output terminals are in a closed state. Integrated module U5 is implemented using commercially available normally open optocouplers, such as chips with models AQY211 and AQY212GS. When there is no input signal at its input terminal, its output terminals are in a disconnected state.

[0031] The positive output of integrated module U1 is connected to the positive input of integrated module U2. The negative input of integrated module U2 is connected to the positive input of U3. The negative input of integrated module U3 is connected to the positive input of U4. The negative input of integrated module U4 is connected to the positive input of U5. The LED1 is connected in series with the positive input of integrated module U5 and then connected to the negative output of integrated module U1.

[0032] The positive output of integrated module U2 is connected to the anode of diode D1 and the base of PNP transistor T1. The emitter of transistor T1, the cathode of diode D1, and the cathode of diode D2 are all connected to the gates of MOSFETs W1-W2. The collector of transistor T1 and the anode of diode D2 are connected to the sources of MOSFETs W1-W2. A bidirectional transient voltage suppressor diode TVS1 is connected in parallel between the drains of MOSFETs W1-W2. MOSFETs W1-W2 are connected in series to form the normally open contacts of this electronic relay. Terminals A1-A2, respectively, from the drains of MOSFETs W1-W2, are the two terminals of the normally open contacts. Integrated module U2 is the driver module for the aforementioned normally open contacts.

[0033] The positive output terminal of integrated module U3 is simultaneously connected to the anode of diode D3, the cathode of diode D3 is connected to the positive terminal of battery B1, and the negative terminal of battery B1 is connected to the negative output terminal of integrated module U3. A resistor R3 is connected in parallel between the positive and negative output terminals of integrated module U3. Battery B1 is the aforementioned built-in power source, implemented using a rechargeable battery (such as a lithium battery).

[0034] The positive output of integrated module U4 is connected to the positive terminal of battery B1. The negative output of integrated module U4 is simultaneously connected to the cathode of diode D4, one end of resistor R4, and the gate of MOSFETs W3-W4. The other end of resistor R4 is connected to the negative output of integrated module U5. The sources of MOSFETs W3-W4, the positive output of integrated module U5, and the anode of diode D4 are simultaneously connected to the negative terminal of battery B1. A bidirectional transient voltage suppressor diode (TVS2) is connected in parallel between the drains of MOSFETs W3-W4. MOSFETs W3-W4 are connected in series to form the normally closed contacts of this electronic relay. Terminals B1-B2, respectively, from the drains of MOSFETs W3-W4, are the two terminals of the normally closed contacts. Integrated modules U3-U5 are connected in series to form the above-mentioned normally closed contact drive module. Diodes D4 and D2 are fast recovery diodes, effectively preventing the MOSFETs from being electrostatically damaged.

[0035] The specific working process and working principle are as follows: When there is no trigger signal input at the input terminal of integrated module U1, there is no input signal at the input terminals of integrated modules U2~U5, there is no output voltage at the output terminal of integrated module U2, and MOSFETs W1~W2 are cut off. At this time, the circuit connected between terminals A1 and A2 is in an open state.

[0036] Since integrated module U4 is a normally closed optocoupler, its output is in a low-impedance state, and integrated module U5 is a normally open optocoupler, its output is in a high-impedance state. The voltage signal output from the positive terminal of battery B1 is applied to the gate of MOSFETs W3~W4 through the output of integrated module U4, driving MOSFETs W3~W4 to conduct and become normally closed. At this time, the signal applied between terminals B1 and B2 can be bidirectionally conducted using the parasitic diodes in MOSFETs W3~W4. Specifically: when the load is a DC load, a DC signal flows between the drains of MOSFETs W3~W4, and the DC signal conducts through the parasitic diodes in MOSFETs W3 and W4, or through the parasitic diodes in MOSFETs W4 and W3; when the load is an AC load, the AC signal conducts through the parasitic diodes in MOSFETs W3 and W4 and the parasitic diodes in MOSFETs W4 and W3 respectively during the positive and negative half-cycles of the AC signal.

[0037] When a trigger signal is input to the input terminal of integrated module U1, the positive DC voltage signal output from the positive terminal of integrated module U1 passes through the input terminals of integrated modules U2~U5 in sequence and returns to the negative terminal of integrated module U1 to form a circuit. At the same time, it drives the light-emitting diode LED1 to light up for power supply indication.

[0038] When a power supply signal is applied to the input terminal of integrated module U2, the voltage signal output from its output terminal is simultaneously applied to the gate of MOSFETs W1~W2, driving MOSFETs W1~W2 to conduct. As can be seen from the above, regardless of whether the load applied to terminals A1 and A2 is AC or DC, the load current can form a path through the parasitic diodes in MOSFETs W1 and W2, or / and the parasitic diodes in MOSFETs W2 and W1, thus achieving bidirectional conduction.

[0039] At this time, after the power supply signal is applied to the input terminal of the integrated module U3, the voltage signal output by the output terminal of the integrated module U3 charges the battery B1 through the diode D3. By setting the diode D3, it is possible to prevent the battery B1 from supplying power to the output terminal of the integrated module U3 in reverse.

[0040] After a power supply signal is applied to the input terminal of integrated module U4, its output terminal is disconnected, changing from a low-resistance state to a high-resistance state. After a power supply signal is applied to the input terminal of integrated module U5, its output terminal is closed, changing from a high-resistance state to a low-resistance state. Therefore, battery B1 cannot apply a voltage signal to the gate of MOSFETs W3~W4 through the output terminal of integrated module U4. MOSFETs W3~W4 are turned off, thus disconnecting the circuit between terminals B1 and B2.

[0041] Example 2: like Figure 3 As shown, in this embodiment, the integrated chip U1' is a commercially available rectifier chip. Its input terminal is the input terminal of the drive signal, used to connect the drive signal that drives the electronic relay. As mentioned above, the drive signal can be a DC signal or an AC signal. A step-down circuit consisting of a capacitor C6' and a resistor R11' connected in parallel is connected in series at one of the input terminals of the integrated chip U1'. The positive terminal of the output terminal of the integrated chip U1' is simultaneously connected to the positive terminal of capacitor C1', one end of capacitor C2', the cathode of Zener diode D5', and one end of resistor R5'. The other end of resistor R5' is connected to the anode of LED D1'. The negative terminal of the output terminal of the integrated chip U1' is simultaneously connected to the negative terminal of capacitor C1', the other end of capacitor C2', the anode of Zener diode D5', and the cathode of LED D1'. LED D1' is an indicator light used to indicate the operating status of the electronic relay, and resistor R5' is a current-limiting resistor for LED D1'.

[0042] Figure 4The circuit shown is a high-frequency oscillation circuit. The positive output terminal of the power input unit is connected in series with diode D4', and then simultaneously connected to resistors R6'~R7' and one end of resistor R3'. The other end of resistor R3' leads to output terminal B. The other end of resistor R6' is connected to one end of capacitor C4' and the base of transistor T2'. The other end of capacitor C4' leads to output terminal A, and the collector of transistor T2' leads to output terminal C.

[0043] The other end of resistor R7' is connected to the base of transistor T1', one end of resistor R2', and the anode of diode D3'. The cathode of transistor T3' is connected to the anode of diode D2', and the cathode of transistor T2' is connected to the negative output terminal of the power input unit. The other end of resistor R2' and the emitter of transistor T1' are connected to one end of resistor R1' and one end of capacitor C5'. The other end of resistor R1' is connected to the negative output terminal of the power input unit and one end of resistor R4'. The other end of resistor R4' is also connected to the other end of capacitor C5', the collector of transistor T1', the emitter of transistor T2', and one end of resistor R9'. The other end of resistor R9' is connected to the collector of transistor T2'.

[0044] Resistors R3', R6'~R7', capacitors C5' and C6', and transistors T1'~T2' form a rectangular wave oscillation circuit, used to output a rectangular oscillation wave signal with a frequency of 200kHz. Diodes D2'~D3', resistors R2', R4', and R9' provide a stable voltage for the operation of transistors T1'~T2'. By using diode D4', the rectangular oscillation wave signal can be effectively prevented from interfering with the power input unit.

[0045] like Figure 5 As shown, pins 1 to 3 on the primary side of high-frequency transformer B1' are connected to the aforementioned output terminals A to C, respectively. On the secondary side of high-frequency transformer B1', pin 4 of high-frequency transformer B1' is connected in series with diode D6' and resistor R10', and then simultaneously connected to the cathode of diode D1', one end of capacitor C3', one end of resistor R8', the positive input terminal of integrated chip U2', and the gates of MOSFETs W1' to W2'.

[0046] Pin 5 of the high-frequency transformer B1' is simultaneously connected to the anode of diode D1', the other end of capacitor C3', the other end of resistor R8', the source of MOSFETs W1'~W2', and the negative input terminal of integrated chip U4'. A bidirectional transient voltage suppressor diode TVS1' is connected in parallel between the drains of MOSFETs W1'~W2'. MOSFETs W1'~W2' are connected in series to form the normally open contact of this electronic relay, and terminals A1~A2, respectively, are the two terminals of the normally open contact. Figure 3 The circuit shown Figure 4The circuit shown, along with the high-frequency transformer B1', forms a normally open contact drive module.

[0047] Integrated modules U2' to U4' are all optocoupler modules. Integrated module U2' uses commercially available photovoltaic optocouplers, such as the TLP3905 and AQY1121 optocoupler chips. The characteristic of photovoltaic optocouplers is that when an input signal is applied to its input terminal, its output terminal can output a corresponding DC signal. Integrated chip U3' uses commercially available normally closed optocouplers, such as the AQY414 and AQY412 chips. When there is no input signal at its input terminal, its output terminals are in a closed state. Integrated module U4' uses commercially available normally open optocouplers, such as the AQY211 and AQY212GS chips. When there is no input signal at its input terminal, its output terminals are in an open state.

[0048] The negative input terminal of integrated module U2' is connected to the positive input terminal of U3', and the negative input terminal of integrated module U3' is connected to the positive input terminal of U4'. The positive output terminal of integrated module U2' is also connected to the anode of diode D7', the cathode of diode D7' is connected to the positive terminal of battery B1, and the negative terminal of battery B1 is connected to the negative output terminal of integrated module U2'. A resistor R12' is connected in parallel between the positive and negative output terminals of integrated module U2'.

[0049] The positive output of integrated module U3' is connected to the positive terminal of battery B1. The negative output of integrated module U3' is simultaneously connected to the cathode of diode D8', one end of resistor R13', and the gate of MOSFETs W3'~W4'. The other end of resistor R13' is connected to the negative output of integrated module U4'. The source of MOSFETs W3'~W4', the positive output of integrated module U4', and the anode of diode D8' are simultaneously connected to the negative terminal of battery B1. A bidirectional transient voltage suppressor diode TVS2' is connected in parallel between the drains of MOSFETs W3'~W4'. MOSFETs W3'~W4' are connected in series to form the normally closed contacts of this electronic relay. Terminals B1~B2, respectively, from the drains of MOSFETs W3'~W4', are the two terminals of the normally closed contacts. Integrated modules U2'~U4' are connected in series to form the above-mentioned normally closed contact drive module. Diode D8' is a fast recovery diode, effectively preventing the MOSFETs from being electrostatically damaged.

[0050] The specific working process and working principle are as follows: When there is no trigger signal input at the input terminal of integrated module U1', there is no input signal at the input terminals of integrated modules U2'~U4', and MOS transistors W1'~W2' are cut off. At this time, the circuit connected between terminals A1 and A2 is in an open state.

[0051] Since integrated module U3' is a normally closed optocoupler, its output terminal is in a low-resistance state, and integrated module U4' is a normally open optocoupler, its output terminal is in a high-resistance state, the voltage signal output from the positive terminal of battery B1 is loaded onto the gate of MOSFETs W3'~W4' through the output terminal of integrated module U3', driving MOSFETs W3'~W4' to conduct and become normally closed. At this time, the signal applied between terminals B1 and B2 can be bidirectionally conducted using the parasitic diodes within MOSFETs W3' to W4'. Specifically: when the load is a DC load, a DC signal flows between the drains of MOSFETs W3' and W4', and the DC signal is turned on through the parasitic diodes within MOSFETs W3' and W4', or through the parasitic diodes within MOSFETs W4' and W3'; when the load is an AC load, during the positive and negative half-cycles of the AC signal, the AC signal is turned on through the parasitic diodes within MOSFETs W3' and W4', and the parasitic diodes within MOSFETs W4' and W3', respectively.

[0052] When a trigger signal is input to the input terminal of integrated module U1', regardless of whether the drive signal is DC or AC, integrated module U1' outputs a DC signal. This DC signal enters the aforementioned high-frequency oscillation circuit. A rectangular wave oscillation circuit, composed of resistors R3', resistors R6'~R7', capacitors C5' and C4', and transistors T1'~T2', generates a rectangular oscillation wave signal. This rectangular oscillation wave signal is then connected to the primary side of high-frequency transformer B1', isolated and coupled to the secondary side via diode D6', resistor R8', and resistor... R10', capacitor C3', and diode D1' effectively ensure the reliable operation of MOSFETs W1'~W2', while reducing the output resistance of the drive circuit and increasing the charging and discharging speed of the gates of MOSFETs W1'~W2'. Diode D6' also serves as an isolation element, effectively preventing the adverse effects of back induced electromotive force in the DC circuit when the load is a DC load. When the drive signal is applied to the gate of MOSFETs W1'~W2', MOSFETs W1'~W2' conduct, which is equivalent to the contacts of this electronic relay closing. The parasitic diodes inside MOSFETs W1'~W2' are used for auxiliary conduction.

[0053] Meanwhile, the signal at the output terminal of the isolation secondary side of the high-frequency transformer B1' is applied to the positive input terminal of the integrated module U2'. After the power supply signal is applied to the input terminal of the integrated module U2', the voltage signal output by the output terminal of the integrated module U2' charges the battery B1 through the diode D7'. By setting the diode D7', the reverse power supply from the battery B1 to the output terminal of the integrated module U3 can be prevented.

[0054] When a power supply signal is applied to the input terminal of integrated module U3', its output terminal is disconnected, changing from a low-resistance state to a high-resistance state. When a power supply signal is applied to the input terminal of integrated module U4', its output terminal is closed, changing from a high-resistance state to a low-resistance state. Therefore, battery B1 cannot apply a voltage signal to the gate of MOSFETs W3'~W4' through the output terminal of integrated module U4, and MOSFETs W3'~W4' are cut off, thus disconnecting the circuit between terminals B1 and B2.

[0055] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention in any other way. Any person skilled in the art may make changes or modifications to the above-disclosed technical content to create equivalent embodiments. However, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the protection scope of the present invention.

Claims

1. An AC / DC universal electronic relay, comprising a power input module, wherein a trigger signal is connected to the input terminal of the power input module, and the trigger signal is an AC signal or a DC signal, characterized in that: It is equipped with normally open contacts and normally closed contacts. The output terminal of the normally open contact is connected to a DC circuit or an AC circuit, and the output terminal of the normally closed contact is connected to a DC circuit or an AC circuit. A normally open contact driver module and a normally closed contact driver module are connected to the output terminal of the power input module. The input terminals of the normally open contact driver module and the normally closed contact driver module are connected in series to the output terminal of the power input module. The output of the normally open contact driver module is connected to the input of the normally open contact; The normally closed contact drive module includes a photovoltaic optocoupler, a normally open optocoupler, and a normally closed optocoupler, with the input terminals of the photovoltaic optocoupler, normally open optocoupler, and normally closed optocoupler connected in series. An internal power supply is provided to drive the normally closed contact. The output of the normally closed contact drive module is connected to the connection circuit between the internal power supply and the normally closed contact. The voltage signal output from the positive terminal of the internal power supply is connected to the normally closed contact through the output of the normally closed optocoupler.

2. The AC / DC universal electronic relay according to claim 1, characterized in that: The normally open contact drive module uses a photovoltaic optocoupler, and the output of the photovoltaic optocoupler is connected to the input of the normally open contact.

3. The AC / DC universal electronic relay according to claim 2, characterized in that: The normally open contact includes two MOSFETs connected in series. The gates of the two MOSFETs are connected to the positive output of the photovoltaic optocoupler, the sources of the two MOSFETs are connected to the negative output of the photovoltaic optocoupler, and the drains of the two MOSFETs are the terminals of the normally open contact.

4. The AC / DC universal electronic relay according to claim 1, characterized in that: The normally closed contact includes two MOS transistors connected in series. The gates of the two MOS transistors are connected to the positive output of the built-in power supply through the output terminal of the normally open optocoupler, the sources of the two MOS transistors are connected to the negative output of the built-in power supply, and the drains of the two MOS transistors are the terminals of the normally closed contact.

5. The AC / DC universal electronic relay according to claim 1, characterized in that: The positive output terminal of the photovoltaic optocoupler is connected in series with a diode and then connected to the positive terminal of the built-in power supply. The negative terminal of the built-in power supply is connected to the negative output terminal of the photovoltaic optocoupler.

6. The AC / DC universal electronic relay according to claim 1, characterized in that: A bidirectional transient voltage suppressor diode is connected in parallel across the output terminals of the normally open contact, and a bidirectional transient voltage suppressor diode is connected in parallel across the output terminals of the normally closed contact.

7. The AC / DC universal electronic relay according to claim 1, characterized in that: The power input module is a rectifier bridge circuit.

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