Energy-saving intelligent solid-state relay

Abstract

The utility model discloses an energy-saving intelligent solid-state relay. An intelligent solid-state relay body in the energy-saving intelligent solid-state relay comprises an aluminum alloy heat dissipation shell, a function induction PCB, a power semiconductor chip and a control panel. The radiator is arranged on the aluminum alloy heat dissipation shell, and the function induction PCB is fixed on a leading-out terminal of the power semiconductor chip. The function induction PCB comprises a plurality of heat-sensitive sensors, the intelligent solid-state relay body is further filled with heat-conducting resin, and the heat-sensitive sensors are arranged at the positions, tightly attached to the power semiconductor chip, in the heat-conducting resin. And the radiator, the leading-out wire of the function induction PCB and the leading-out terminal are connected with the control panel. Therefore, the junction temperature and the shell temperature of the power semiconductor chip can be determined through the plurality of heat-sensitive sensors, and the current of the power semiconductor chip can be controlled, that is, after the junction temperature exceeds a certain temperature, the output current is automatically reduced and limited within a certain range, and meanwhile, the shell temperature and the radiator are combined, so that the energy-saving effect is achieved.

Description

Technical Field

[0001] This utility model relates to the field of relay technology, and in particular to an energy-saving intelligent solid-state relay. Background Technology

[0002] The main failure and damage forms of conventional solid-state relays are over-temperature, short circuit, and over-voltage. Over-temperature damage is caused by internal thermal fatigue, resulting from improper heat dissipation design, unreasonable drive circuit design, and changes in external load. Short-circuit damage is caused by poor load insulation and bridge short circuits caused by external debris. Over-voltage damage is caused by rising bus voltage, external noise (lightning surges), and peak turn-off voltage from inductive loads. These failure modes cover more than 95% of solid-state relay failures.

[0003] Solid-state relays are commonly used in various industrial heating equipment. In enclosed spaces, temperature controllers are commonly used, where a desired operating temperature is set, and a solid-state relay is driven as a switch (power on / off) to maintain the set temperature. However, in an open or portable simple heating device, the heating area is affected by the ambient temperature; for example, the temperature difference between winter and summer can reach 40-50℃. The required temperature at the operating point (area) is relatively fixed. Setting the heating equipment power according to the winter ambient temperature would result in significant energy waste in summer. Utility Model Content

[0004] This invention provides an energy-saving intelligent solid-state relay. It can determine the junction temperature and case temperature of the power semiconductor chip through multiple thermistors and control the current of the power semiconductor chip. That is, when the junction temperature exceeds a certain temperature, the output current is automatically reduced and limited to a certain range. At the same time, combined with the case temperature and heat sink, energy saving effect is achieved.

[0005] In a first aspect, the present invention provides an energy-saving intelligent solid-state relay, which includes a heat sink and an intelligent solid-state relay body.

[0006] The intelligent solid-state relay body includes an aluminum alloy heat dissipation shell, a functional sensing PCB board, a power semiconductor chip, and a control board, with the heat sink disposed on the aluminum alloy heat dissipation shell;

[0007] The functional sensing PCB board is fixed on the lead-out terminals of the power semiconductor chip;

[0008] The functional sensing PCB board includes multiple thermal sensors, and the intelligent solid-state relay body is also filled with thermally conductive resin. The thermal sensors are disposed in the thermally conductive resin in close contact with the power semiconductor chip.

[0009] The heat sink, the lead wires of the functional sensing PCB board, and the lead terminals are all connected to the control board.

[0010] Optionally, the power semiconductor chip includes a first enhanced thyristor and a second enhanced thyristor, wherein the first enhanced thyristor and the second enhanced thyristor are connected in reverse parallel.

[0011] The functional sensing PCB board includes an over-temperature protection circuit, which includes a first thermistor and a second thermistor.

[0012] The first end of the first thermistor is electrically connected to the first input end of the control board, and the second end of the first thermistor is electrically connected to the trigger electrode of the second enhanced thyristor.

[0013] The first end of the second thermistor is electrically connected to the second input end of the control board, and the second end of the second thermistor is electrically connected to the trigger electrode of the first enhanced thyristor.

[0014] Both the first and second thermistors are PCT temperature sensors.

[0015] Optionally, the intelligent solid-state relay body also includes a first indicator light;

[0016] The first indicator light is connected in parallel to the output terminal of the control board;

[0017] The functional sensing PCB board also includes an overvoltage protection circuit, which includes a varistor, a current-limiting resistor, a bidirectional trigger diode, a second indicator light, and a first small rectifier bridge.

[0018] The positive terminals of the current-limiting resistor, the bidirectional trigger diode, and the second indicator light are connected in series and then in parallel with the varistor. The varistor is connected in parallel with the first enhanced thyristor and the second enhanced thyristor.

[0019] The second indicator light is electrically connected to the input terminal of the first small rectifier bridge, and outputs a working status signal after rectification to indicate whether there is a working voltage at the working terminal of the power semiconductor chip;

[0020] The first indicator light is used to indicate whether there is a control voltage at the control terminal of the control board.

[0021] Optionally, the power semiconductor chip includes an insulated transistor;

[0022] The functional sensing PCB board includes an over-temperature protection circuit, which includes a first thermistor and a second thermistor.

[0023] The first end of the first thermistor is electrically connected to the first input end of the control board, and the second end of the first thermistor is electrically connected to the base of the insulating transistor.

[0024] The first end of the second thermistor is electrically connected to the ground terminal, and the second end of the second thermistor is electrically connected to the base of the insulating transistor.

[0025] Optionally, the first thermistor is a PCT temperature sensor, and the second thermistor is an NTC temperature sensor.

[0026] Optionally, the intelligent solid-state relay body also includes a first indicator light;

[0027] The first indicator light is connected in parallel to the output terminal of the control board;

[0028] The functional sensing PCB board also includes an overvoltage protection circuit, which includes a varistor, a current-limiting resistor, and a second indicator light.

[0029] The varistor is connected in parallel between the collector and emitter of the insulated transistor;

[0030] The current-limiting resistor and the positive terminal of the second indicator light are connected in series and then connected in parallel with the varistor;

[0031] The second indicator light is used to indicate whether there is a working voltage at the working terminal of the power semiconductor chip, and the first indicator light is used to indicate whether there is a control voltage at the control terminal of the control board.

[0032] Optionally, the intelligent solid-state relay body also includes a mounting base plate;

[0033] The mounting substrate includes a T-shaped mounting substrate, and the power semiconductor chip is fixed on the T-shaped mounting substrate;

[0034] The mounting base plate is welded onto the aluminum alloy heat sink casing.

[0035] Optionally, the functional sensing PCB board may also include an overcurrent protection circuit;

[0036] The overcurrent protection circuit includes an adjustment resistor, an output resistor, a second miniature rectifier bridge, a third enhanced thyristor, a current sensing sensor, and an optocoupler.

[0037] The coil of the current sensing sensor is sleeved on the lead-out terminal, and the regulating resistor is connected in parallel across the two ends of the coil; the input end of the second miniature rectifier bridge is electrically connected to the two ends of the coil, and the output end of the second miniature rectifier bridge is electrically connected to the input end of the optocoupler.

[0038] The positive terminal of the third enhanced thyristor is electrically connected to the first output terminal of the control board and the first output terminal of the optocoupler, the negative terminal of the third enhanced thyristor is electrically connected to the second output terminal of the control board, and the trigger terminal of the third enhanced thyristor is electrically connected to the second output terminal of the optocoupler through the output resistor.

[0039] Optionally, the functional sensing PCB board may also include an overcurrent protection circuit;

[0040] The overcurrent protection circuit includes a shunt measuring resistor, an adjusting resistor, an output resistor, a fourth enhanced thyristor, and an optocoupler;

[0041] The shunt measuring resistor is connected in series between the emitter of the insulated transistor and the ground terminal;

[0042] The regulating resistor is connected in series between the emitter of the insulating transistor and the input terminal of the optocoupler;

[0043] The positive terminal of the fourth enhanced thyristor is electrically connected to the first output terminal of the control board and the first output terminal of the optocoupler, the negative terminal of the fourth enhanced thyristor is electrically connected to the second output terminal of the control board, and the trigger terminal of the fourth enhanced thyristor is electrically connected to the second output terminal of the optocoupler through the output resistor.

[0044] Optionally, the energy-saving intelligent solid-state relay further includes a solder layer;

[0045] The solder layer is disposed between the mounting substrate and the aluminum alloy heat dissipation shell.

[0046] This utility model discloses an energy-saving intelligent solid-state relay. The relay body includes an aluminum alloy heat sink housing, a functional sensing PCB board, a power semiconductor chip, and a control board. The heat sink is mounted on the aluminum alloy heat sink housing, and the functional sensing PCB board is fixed to the leads of the power semiconductor chip. The functional sensing PCB board includes multiple thermistors, and the relay body is filled with thermally conductive resin. The thermistors are positioned within the resin, closely attached to the power semiconductor chip. The heat sink, the leads of the functional sensing PCB board, and the leads are all connected to the control board. Thus, the junction temperature and case temperature of the power semiconductor chip can be determined by the multiple thermistors, and the current of the power semiconductor chip can be controlled. Specifically, if the junction temperature exceeds a certain level, the output current is automatically reduced and limited within a certain range. Combined with the case temperature and the heat sink, energy-saving effects are achieved. Attached Figure Description

[0047] Figure 1 This is a schematic diagram of the structure of an energy-saving intelligent solid-state relay provided in an embodiment of this utility model;

[0048] Figure 2 This is a schematic diagram illustrating the temperature-current relationship of an energy-saving intelligent solid-state relay provided in this embodiment of the present invention;

[0049] Figure 3 This is a partial circuit diagram of an energy-saving intelligent solid-state relay provided in an embodiment of the present invention;

[0050] Figure 4 This is a partial circuit diagram of another energy-saving intelligent solid-state relay provided in an embodiment of the present invention;

[0051] Figure 5 This is a schematic diagram of the structure of a mounting substrate provided in an embodiment of this utility model. Detailed Implementation

[0052] To make the objectives, technical solutions, and advantages of this utility model clearer, the technical solutions of this utility model will be fully described below with reference to the accompanying drawings of the embodiments of this utility model and through specific implementation methods. Obviously, the described embodiments are only some, not all, of the embodiments of this utility model. All other embodiments obtained by those skilled in the art based on the embodiments of this utility model without creative effort fall within the protection scope of this utility model.

[0053] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this utility model are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the utility model described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0054] Figure 1 This is a schematic diagram of the structure of an energy-saving intelligent solid-state relay provided in an embodiment of the present invention. Figure 2 This is a schematic diagram illustrating the temperature-current relationship of an energy-saving intelligent solid-state relay provided in an embodiment of this utility model. Figure 1 and Figure 2 As shown, the energy-saving intelligent solid-state relay includes a heat sink 02 and an intelligent solid-state relay body 01. The intelligent solid-state relay body 01 includes an aluminum alloy heat sink housing 10, a functional sensing PCB board 20, a power semiconductor chip 30, and a control board 40. The heat sink 02 is mounted on the aluminum alloy heat sink housing 10. The functional sensing PCB board 20 is fixed to the lead-out terminals 310 of the power semiconductor chip 30. The functional sensing PCB board 20 includes multiple thermal sensors (not shown in the figure). The intelligent solid-state relay body 01 is also filled with thermally conductive resin, and the thermal sensors are disposed in the thermally conductive resin in close contact with the power semiconductor chip 30. The heat sink, the lead-out wires of the functional sensing PCB board 20, and the lead-out terminals 310 are all connected to the control board 40.

[0055] Specifically, the power semiconductor chip 30 can be a high-power bidirectional thyristor or an enhanced power control device formed by two high-power unidirectional thyristors connected in reverse parallel, both of which can be applied to AC control circuits. Furthermore, the power semiconductor chip 30 can also be a high-power, high-performance insulated transistor or a high-power field-effect transistor for DC control circuits. The power semiconductor chip 30 can be configured into single-core groups (AC unidirectional or DC applications), dual-core groups (AC unidirectional enhancement type), three-core groups (three-phase AC), and six-core groups (three-phase AC enhancement type) according to different functions. Because the power semiconductor chip 30 has a voltage drop, it will inevitably generate heat during operation. For example, when a 20A current flows through it, approximately 10-20W of power consumption will be generated. This power consumption is converted into temperature, which is the operating temperature (junction temperature) of the power semiconductor chip 30. In addition, the power semiconductor chip 30 is mounted on an aluminum alloy heat sink 10, and the ambient temperature and the heat generated by the power semiconductor chip 30 together form the temperature of the aluminum alloy heat sink 10 (case temperature). In this embodiment of the invention, the operating temperature of the power semiconductor chip 30 is detected by multiple thermistors disposed in thermally conductive resin and closely attached to the chip. Specifically, a thermistor is a sensor capable of converting temperature changes into electrical signals, utilizing the characteristic that the resistance of a semiconductor material changes with temperature. For example,... Figure 2 As shown, the blue and green lines represent the temperature and current relationship of the energy-saving intelligent solid-state relay. When the operating temperature of the power semiconductor chip 30 rises to 110°C, the resistance of the thermistor increases with the operating temperature, thereby reducing the current of the power semiconductor chip 30 and enabling the power semiconductor chip 30 to operate intelligently at an appropriate operating current. When the operating temperature of the power semiconductor chip 30 rises to 120°C, the power semiconductor chip 30 shuts off the main operating circuit, thus ensuring that the power semiconductor chip 30 will not overheat and be damaged, and automatically balancing to find an optimal operating current.

[0056] Furthermore, the heat sink 02 is mounted on the aluminum alloy heat sink housing 10. The heat generated by the junction temperature of the power semiconductor chip 30 is conducted through the aluminum alloy heat sink housing 10 and the heat sink 02, thereby reducing the junction temperature. This is a reciprocal relationship. Without the heat sink 02, the operating temperature (junction temperature) of the power semiconductor chip 30 would continuously rise, eventually damaging the chip. However, if the rate of heat conduction by the heat sink 02 exceeds the heat generated by the junction temperature, the junction temperature will decrease, reaching equilibrium under certain conditions. The housing temperature also affects the temperature rise range of the power semiconductor chip 30's junction temperature. For example, in summer, the junction temperature rises from 40°C to 110°C, while in winter, it rises from 0°C to 110°C. Therefore, the operating environment of the energy-saving intelligent solid-state relay is determined based on the housing temperature. A certain margin is set according to the operating environment, and a suitable heat sink area is selected to ensure heat dissipation conditions, thereby achieving energy-saving effects.

[0057] It should be noted that two different sizes of heat sinks were used to test the energy-saving effect when testing the above content. The test results are shown in the table below:

[0058]

[0059]

[0060] As can be seen from the above, based on the intelligent solid-state relay body (including the thermal sensor) provided in this embodiment of the present invention, energy-saving effects can be achieved by using heat sinks with different heat dissipation areas.

[0061] It should also be noted that there is a certain relationship between shell temperature and junction temperature, and thus, after determining the junction temperature, the shell temperature can be determined based on this relationship.

[0062] In summary, the intelligent solid-state relay body in this embodiment includes an aluminum alloy heat sink housing, a functional sensing PCB board, a power semiconductor chip, and a control board. The heat sink is mounted on the aluminum alloy heat sink housing, and the functional sensing PCB board is fixed to the leads of the power semiconductor chip. The functional sensing PCB board includes multiple thermistors, and the intelligent solid-state relay body is also filled with thermally conductive resin. The thermistors are positioned within the thermally conductive resin, closely attached to the power semiconductor chip. The heat sink, the leads of the functional sensing PCB board, and the leads are all connected to the control board. Thus, the junction temperature and case temperature of the power semiconductor chip can be determined by multiple thermistors, and the current of the power semiconductor chip can be controlled. Specifically, when the junction temperature exceeds a certain level, the output current is automatically reduced and limited to a certain range. Combined with the case temperature and the heat sink, energy-saving effects are achieved.

[0063] Optionally, based on the above embodiments, Figure 3 This is a partial circuit diagram of an energy-saving intelligent solid-state relay provided in an embodiment of this utility model. (See diagram below.) Figure 1 and Figure 3 The diagram shown illustrates the structure and circuit of an AC single-phase intelligent solid-state relay. (See also...) Figure 3The power semiconductor chip 30 includes a first enhanced silicon controlled rectifier (SCR1) and a second enhanced silicon controlled rectifier (SCR2). The first enhanced SCR1 and the second enhanced SCR2 are connected in reverse parallel. The functional sensing PCB board 20 includes an over-temperature protection circuit 210, which includes a first thermistor R1 and a second thermistor R2. The first terminal of the first thermistor R1 is electrically connected to the first input terminal Vin1 of the control board 40, and the second terminal of the first thermistor R1 is electrically connected to the trigger electrode of the second enhanced SCR2. The first terminal of the second thermistor R2 is electrically connected to the second input terminal Vin2 of the control board 40, and the second terminal of the second thermistor R2 is electrically connected to the trigger electrode of the first enhanced SCR1. Both the first thermistor R1 and the second thermistor R2 are PCT temperature sensors.

[0064] Specifically, the control board 40 receives an electrical signal for a control switch. An on / off control signal is input from the first input terminal Vin1 and the second input terminal Vin2. This signal, transmitted through the first thermistor R1 and the second thermistor R2, triggers the first enhanced thyristor SCR1 and the second enhanced thyristor SCR2, thereby driving the main circuit to turn on or off. The first thermistor R1 and the second thermistor R2 are respectively mounted on the first enhanced thyristor SCR1 and the second enhanced thyristor SCR2. They are encapsulated in a high thermal conductivity insulating material formed by mixing silicon dioxide particles and IC-specific adhesive, enabling real-time heat conduction to maintain the chip's operating temperature. This causes the resistance values ​​of the first thermistor R1 and the second thermistor R2 to change accordingly with the chip's operating temperature. The maximum set temperature is typically 120℃. If this set temperature is exceeded, the first enhanced thyristor SCR1 and the second enhanced thyristor SCR2 will turn off the main circuit. This is also a process of automatically finding the thermal equilibrium operating current. This ensures that the power semiconductor chip 30 will not overheat and be damaged, and can automatically balance to find an optimal operating point.

[0065] Optional, see below Figure 1 and Figure 3The intelligent solid-state relay body also includes a first indicator light (not shown in the figure). The first indicator light is connected in parallel to the output terminal of the control board 40. The functional sensing PCB board 20 also includes an overvoltage protection circuit 220, which includes a varistor R3, a current-limiting resistor R4, a bidirectional trigger diode D1, a second indicator light D2, and a first miniature rectifier bridge D3. The positive terminals of the current-limiting resistor R4, the bidirectional trigger diode D1, and the second indicator light D2 are connected in series and then in parallel with the varistor R3. The varistor R3 is connected in parallel with the first enhanced silicon controlled rectifier SCR1 and the second enhanced silicon controlled rectifier SCR2. The second indicator light D2 is electrically connected to the input terminal of the first miniature rectifier bridge D3, and outputs a working status signal after rectification to indicate whether there is a working voltage at the working terminal of the power semiconductor chip 30. The first indicator light is used to indicate whether there is a control voltage at the control terminal of the control board 40.

[0066] Specifically, the overvoltage protection circuit 220 is a special display and absorption circuit composed of a varistor R3, a current-limiting resistor R4, a trigger diode D1, and a second indicator light D2. It can absorb excessively high voltages and noise generated by the external environment (lightning surges), as well as peak shutdown voltages caused by inductive loads. It can also display the real-time operating status of the power semiconductor chip. Furthermore, the intelligent solid-state relay body also includes a first indicator light. The first indicator light is connected in parallel at the output terminal of the control board 40 to indicate whether there is a control voltage at the control terminal of the control board 40. The first indicator light and the second indicator light D2 are used to visually represent the operating and fault states of the energy-saving intelligent solid-state relay. For example, since the first indicator light and the second indicator light D2 are both connected in parallel on both sides of the corresponding device, when both the first indicator light and the second indicator light D2 are off, it indicates that the intelligent solid-state relay body has neither a control voltage input nor an operating voltage output, and is in the initial state. When the first indicator light is off and the second indicator light D2 is off, it indicates that there is an operating voltage at the operating terminal of the power semiconductor chip 30. When the first indicator light is on and the second indicator light D2 is off, it indicates that the intelligent solid-state relay body is in the start-up state. When the first indicator light is off and the second indicator light D2 is on, it indicates that the intelligent solid-state relay is in a normal off state. If both the first and second indicator lights D2 are on, or if either the first or second indicator light D2 is off in any state, it indicates that the intelligent solid-state relay is in a fault state. Thus, the operating and fault states of the intelligent solid-state relay can be directly determined by observing the first and second indicator lights D2. Furthermore, the cause of the fault can be identified by which indicator light is off, greatly facilitating the troubleshooting and maintenance of energy-saving intelligent solid-state relays.

[0067] Optionally, based on the above embodiments, see also... Figure 3The functional sensing PCB board 20 also includes an overcurrent protection circuit 230. The overcurrent protection circuit 230 includes an adjusting resistor R5, an output resistor R6, a second miniature rectifier bridge D4, a third enhanced SCR3, a current sensing sensor L, and an optocoupler U1. The coil of the current sensing sensor L is sleeved on the lead terminal 310. The adjusting resistor R5 is connected in parallel across the coil. The input terminal of the second miniature rectifier bridge D4 is electrically connected to both ends of the coil, and the output terminal of the second miniature rectifier bridge D4 is electrically connected to the input terminal of the optocoupler U1. The positive terminal of the third enhanced SCR3 is electrically connected to the first output terminal Vout1 of the control board 40 and the first output terminal of the optocoupler U1, the negative terminal of the third enhanced SCR3 is electrically connected to the second output terminal Vout2 of the control board 40, and the trigger terminal of the third enhanced SCR3 is electrically connected to the second output terminal of the optocoupler U1 through the output resistor R6.

[0068] The overcurrent protection circuit 230 consists of a current sensing sensor L coil wound around the lead terminal 310 of the power semiconductor chip 30. Adjusting resistor R5 adjusts the output voltage of the current sensing sensor L's coil, obtaining a DC voltage through the second small rectifier bridge D4. This DC voltage drives the optocoupler U1 output, which in turn generates switching signals Vout1 and Vout2 through output resistor R6 and the third enhanced thyristor SCR3. This is a forced shutdown signal controlled by the third enhanced thyristor SCR3. Based on the device's operating characteristics, once an overcurrent condition occurs, the overcurrent protection circuit 230 must be shut down for maintenance and the input control signal must be disconnected before it can operate again. A restart process is required to ensure safety. The overcurrent start-up current can be set to 150%, 200%, 300%, etc., depending on the rated capacity of different power semiconductor chips to avoid excessive malfunctions.

[0069] Optional, Figure 4 This is a partial circuit diagram of another energy-saving intelligent solid-state relay provided in an embodiment of this utility model. (See diagram below.) Figure 4 The implementation shown uses an AC three-phase intelligent solid-state relay as an example for illustration.

[0070] For details, see Figure 4The power semiconductor chip 30 includes an insulated transistor T. The functional sensing PCB board 20 includes an over-temperature protection circuit 210, which includes a first thermistor R1 and a second thermistor R2. The first terminal of the first thermistor R1 is electrically connected to the first input terminal Vin1 of the control board 40, and the second terminal of the first thermistor R1 is electrically connected to the base of the insulated transistor T. The first terminal of the second thermistor R2 is electrically connected to the ground terminal GND, and the second terminal of the second thermistor R2 is electrically connected to the base of the insulated transistor T. The first thermistor R1 is a PCT temperature sensor, and the second thermistor R2 is an NTC temperature sensor.

[0071] Specifically, a PWM modulation switch or PLC industrial control signal is input to the first input terminal Vin1 of the control board 40. This signal drives the insulated transistor T through a temperature control circuit composed of the first thermistor R1 and the second thermistor R2. When overheating occurs, the temperature is typically set to 120°C. The resistance values ​​of the first thermistor R1 and the second thermistor R2 change accordingly with the sensed temperature. The first thermistor R1 is a PCT temperature sensor, and its resistance increases with increasing temperature, while the second thermistor R2 is an NTC temperature sensor, and its resistance decreases with increasing temperature. This provides more sensitive protection for the gate of the insulated transistor T and automatically generates a thermal balance function. It intelligently operates at an appropriate operating current. The inclusion of the NTC temperature sensor also significantly helps prevent electrostatic discharge (ESD) damage to the gate of the insulated transistor T, thus providing more comprehensive protection for the power semiconductor chip.

[0072] Optional, see below Figure 4 The intelligent solid-state relay body also includes a first indicator light. The first indicator light is connected in parallel to the output terminal of the control board 40. The functional sensing PCB board 20 also includes an overvoltage protection circuit 220, which includes a varistor R3, a current-limiting resistor R4, and a second indicator light D2. The varistor R3 is connected in parallel to the collector and emitter of the insulated transistor T. The current-limiting resistor R4 and the positive terminal of the second indicator light D2 are connected in series and then in parallel with the varistor R3. The second indicator light D2 is used to indicate whether there is a working voltage at the working terminal of the power semiconductor chip 30, and the first indicator light is used to indicate whether there is a control voltage at the control terminal of the control board 40. It can be understood that the working principle of the overvoltage protection circuit 220 and the working principle of the two indicator lights in the AC three-phase intelligent solid-state relay are the same as those in the AC single-phase intelligent solid-state relay, and will not be repeated here.

[0073] See also Figure 4The functional sensing PCB board 20 also includes an overcurrent protection circuit 230. The overcurrent protection circuit 230 includes a shunt measuring resistor R5, an adjusting resistor R6, an output resistor R7, a fourth enhanced type thyristor (SCR4), and an optocoupler. The shunt measuring resistor R5 is connected in series between the emitter of the insulated transistor T and the ground terminal GND. The adjusting resistor R6 is connected in series between the emitter of the insulated transistor T and the input terminal of the optocoupler U1. The positive terminal of the fourth enhanced type thyristor SCR4 is electrically connected to the first output terminal of the control board 40 and the first output terminal of the optocoupler U1; the negative terminal of the fourth enhanced type thyristor SCR4 is electrically connected to the second output terminal of the control board 40; and the trigger terminal of the fourth enhanced type thyristor SCR4 is electrically connected to the second output terminal of the optocoupler U1 through the output resistor R7. Specifically, the overcurrent and short-circuit protection circuit obtains an operating voltage from the shunt measuring resistor R5 connected in series with the emitter of the high-performance insulated transistor T and the ground terminal GND. The operating voltage of the shunt measuring resistor R5 can be adjusted by adjusting the resistor R6, driving the output of the optocoupler U1. The working principle of the other circuits is the same as that of the AC single-phase intelligent solid-state relay, and will not be explained again.

[0074] Optionally, based on the above embodiments, Figure 5 This is a schematic diagram of a mounting substrate provided in an embodiment of this utility model. See also: Figure 1 and Figure 5 The intelligent solid-state relay body 01 also includes a mounting substrate 50. The mounting substrate 50 includes a T-shaped mounting substrate on which the power semiconductor chip 30 is fixed. Specifically, because the intelligent solid-state relay body 01 is small in size but requires many electrical components, this embodiment of the invention provides a T-shaped mounting substrate for the mounting substrate 50. For example, the T-shaped mounting substrate includes a parallel main board 510 and an additional sub-board 520. The parallel main board 510 and the additional sub-board 520 are cross-welded to form a T-shaped structure, and a welding point 530 is formed at the junction of the parallel main board 510 and the additional sub-board 520. Furthermore, electrical components 540 can be installed on both the parallel main board 510 and the additional sub-board 520. This fully utilizes the internal space of the intelligent solid-state relay body 01, which is beneficial for improving the performance of the intelligent solid-state relay body 01. The mounting substrate 50 is welded to the aluminum alloy heat sink housing 10. In addition, the mounting substrate 50 with the chipset installed can be directly soldered to the aluminum alloy heat sink 10 by forming a solder layer 60 with medium-temperature solder paste, which can increase the heat dissipation area and improve the power density.

[0075] Note that the above description is merely a preferred embodiment of the present invention and the technical principles employed. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and various obvious changes, readjustments, combinations, and substitutions can be made without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments. Many other equivalent embodiments may be included without departing from the concept of the present invention, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. An energy-saving intelligent solid-state relay, characterized in that, the energy-saving intelligent solid-state relay comprises a radiator and an intelligent solid-state relay body; the intelligent solid-state relay body comprises an aluminum alloy heat dissipation shell, a functional sensing PCB board, a power semiconductor chip and a control board, and the radiator is arranged on the aluminum alloy heat dissipation shell; the functional sensing PCB board is fixed on the lead-out terminal of the power semiconductor chip; the functional sensing PCB board comprises a plurality of thermal sensors, and the intelligent solid-state relay body is further filled with a heat-conducting resin, and the thermal sensors are arranged in the heat-conducting resin and tightly contact the power semiconductor chip; the radiator, the lead-out wire of the functional sensing PCB board and the lead-out terminal are connected with the control board.

2. The energy-saving intelligent solid-state relay according to claim 1, characterized in that, the power semiconductor chip comprises a first enhanced thyristor and a second enhanced thyristor, and the first enhanced thyristor is connected in anti-parallel with the second enhanced thyristor; the functional sensing PCB board comprises an over-temperature protection circuit, and the over-temperature protection circuit comprises a first thermal sensor and a second thermal sensor; a first end of the first thermal sensor is electrically connected with a first input end of the control board, and a second end of the first thermal sensor is electrically connected with a trigger electrode of the second enhanced thyristor; a first end of the second thermal sensor is electrically connected with a second input end of the control board, and a second end of the second thermal sensor is electrically connected with a trigger electrode of the first enhanced thyristor; the first thermal sensor and the second thermal sensor are both PCT temperature sensors.

3. The energy-saving intelligent solid-state relay according to claim 2, characterized in that, the intelligent solid-state relay body further comprises a first indicator lamp; the first indicator lamp is connected in parallel with an output end of the control board; the functional sensing PCB board further comprises an over-voltage protection circuit, and the over-voltage protection circuit comprises a pressure-sensitive resistor, a current-limiting resistor, a bidirectional trigger diode, a second indicator lamp and a first small rectifier bridge stack; the current-limiting resistor, the bidirectional trigger diode and the positive electrode of the second indicator lamp are connected in series and connected in parallel with the pressure-sensitive resistor, and the pressure-sensitive resistor is connected in parallel with the first enhanced thyristor and the second enhanced thyristor; the second indicator lamp is electrically connected with the input end of the first small rectifier bridge stack, rectifies and outputs a working state signal, and is used for indicating whether there is a working voltage at the working end of the power semiconductor chip; the first indicator lamp is used for indicating whether there is a control voltage at the control end of the control board.

4. The energy-saving intelligent solid-state relay according to claim 1, characterized in that, the power semiconductor chip comprises an insulated transistor; the functional sensing PCB board comprises an over-temperature protection circuit, and the over-temperature protection circuit comprises a first thermal sensor and a second thermal sensor; a first end of the first thermal sensor is electrically connected with a first input end of the control board, and a second end of the first thermal sensor is electrically connected with a base electrode of the insulated transistor; The first end of the second thermal sensor is electrically connected with the ground terminal, and the second end of the second thermal sensor is electrically connected with the base of the insulated transistor.

5. The energy-saving intelligent solid state relay according to claim 4, characterized in that, The first thermal sensor is a PCT temperature sensor, and the second thermal sensor is an NTC temperature sensor.

6. The energy-saving intelligent solid-state relay according to claim 5, wherein the body of the intelligent solid-state relay further comprises a first indicator light. The first indicator light is arranged in parallel with the output end of the control board. The function sensing PCB further comprises an overvoltage protection circuit, and the overvoltage protection circuit comprises a voltage-dependent resistor, a current-limiting resistor and a second indicator light. The voltage-dependent resistor is arranged in parallel with the collector and the emitter of the insulated transistor. The current-limiting resistor and the anode of the second indicator light are connected in series and are arranged in parallel with the voltage-dependent resistor. The second indicator light is used to indicate whether there is working voltage at the working end of the power semiconductor chip, and the first indicator light is used to indicate whether there is control voltage at the control end of the control board.

7. The energy-saving intelligent solid-state relay according to claim 1, wherein the body of the intelligent solid-state relay further comprises a mounting substrate. The mounting substrate comprises a T-shaped mounting substrate, and the power semiconductor chip is fixed on the T-shaped mounting substrate. The mounting substrate is welded on the aluminum alloy heat dissipation shell.

8. The energy-saving intelligent solid-state relay according to claim 3, wherein the function sensing PCB further comprises an overcurrent protection circuit. The overcurrent protection circuit comprises an adjusting resistor, an output resistor, a second small rectifier bridge stack, a third enhanced thyristor, a current sensing sensor and an optocoupler. The coil of the current sensing sensor is sleeved on the lead-out terminal, the adjusting resistor is arranged in parallel at both ends of the coil, the input end of the second small rectifier bridge stack is electrically connected with both ends of the coil, and the output end of the second small rectifier bridge stack is electrically connected with the input end of the optocoupler. The anode of the third enhanced thyristor is electrically connected with the first output end of the control board and the first output end of the optocoupler, the cathode of the third enhanced thyristor is electrically connected with the second output end of the control board, and the trigger electrode of the third enhanced thyristor is electrically connected with the second output end of the optocoupler through the output resistor.

9. The energy-saving intelligent solid-state relay according to claim 5, wherein the function sensing PCB further comprises an overcurrent protection circuit. The overcurrent protection circuit comprises a shunt measurement resistor, an adjusting resistor, an output resistor, a fourth enhanced thyristor and an optocoupler. The shunt measurement resistor is arranged in series between the emitter of the insulated transistor and the ground terminal. The adjusting resistor is arranged in series between the emitter of the insulated transistor and the input end of the optocoupler. The anode of the fourth enhanced thyristor is electrically connected with the first output end of the control board and the first output end of the optocoupler, the cathode of the fourth enhanced thyristor is electrically connected with the second output end of the control board, and the trigger electrode of the fourth enhanced thyristor is electrically connected with the second output end of the optocoupler through the output resistor. ​ ​ ​ ​ 10. The energy-saving intelligent solid state relay according to claim 7, wherein the energy-saving intelligent solid state relay further comprises a solder layer. The energy-saving intelligent solid state relay further comprises a solder layer. The solder layer is arranged between the mounting substrate and the aluminum alloy heat dissipation shell.

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