Electric water heater control circuit and electric water heater

Abstract

The utility model discloses an electric water heater control circuit and an electric water heater, when the control circuit is applied to the electric water heater, the control circuit detects the working current of a second working module and a first working module, detects the temperature of a power bus, and feeds back the detection result to a controller. When the working modules need to be switched and one relay is adhered, the second working module and the first working module have working currents, the controller controls the first relay and the second relay to be disconnected, and only the working module where the adhesion relay is located works. And the overload operation phenomenon can be effectively avoided. When line aging or poor contact occurs, at the moment, the temperature of the power bus is too high, the controller controls the first relay and the second relay to be switched off, the safety problem caused by the fact that the electric water heater continues to work when line aging or poor contact occurs can be effectively avoided, and then the use safety is improved.

Description

Technical Field

[0001] The utility model relates to a water heater control technology, in particular to an electric water heater control circuit and an electric water heater. Background Art

[0002] An electric water heater is a water heater that uses electricity as an energy source for heating. Some electric water heaters are equipped with multiple high-power working modules, such as a water heater equipped with an upper heating tube and a lower heating tube, or a water heater equipped with a heating tube and a warm air device. To avoid overload, high-power working modules usually cannot operate simultaneously. Existing ones are generally controlled by corresponding relays. Before controlling the relay of one working module to close, the relay of another working module must be controlled to disconnect first. However, if one of the relays becomes stuck and cannot be disconnected normally, the two working modules will still operate simultaneously, posing a safety hazard. At the same time, if the circuit is aging or has poor contact, it is also easy to cause safety problems. Utility Model Content

[0003] One of the technical problems solved by the utility model is to provide an electric water heater control circuit, which can detect the working state of the electric water heater and improve the safety of use.

[0004] The second technical problem solved by the present invention is to provide an electric water heater, which can detect the working status of the electric water heater and improve the safety of use.

[0005] The first technical problem mentioned above is solved by the following technical solution:

[0006] An electric water heater control circuit, comprising:

[0007] Controller;

[0008] a first relay, connected to the controller and configured to control power on and off of the first working module;

[0009] a second relay, connected to the controller, for controlling the on and off of the second working module;

[0010] a first current sampling module, connected to the controller, configured to detect a working current of the first working module and feed the current back to the controller;

[0011] a second current sampling module, connected to the controller, for detecting the operating current of the second operating module and feeding back the current to the controller;

[0012] A temperature sampling module is connected to the controller and is used to detect the temperature of the power bus of the electric water heater and feed it back to the controller.

[0013] The electric water heater control circuit provided by the present utility model, when used in the electric water heater, detects the working current of the second working module and the first working module, as well as the temperature of the power bus, and feeds back the detection results to the controller so as to understand the working status of the electric water heater, provide a basis for subsequent control, and avoid the phenomenon of excessive line temperature and overload operation caused by line aging or poor contact, thereby improving the safety of use.

[0014] In some embodiments of the present invention, the first working module is a heating pipe, and the second working module is a warm air device.

[0015] In some embodiments of the present invention, the first working module is a first heating tube, and the second working module is a second heating tube.

[0016] In some embodiments of the present invention, the first current sampling module and the second current sampling module each include a current transformer, a rectifier unit, a first voltage divider unit, a first filter unit, and a clamping unit;

[0017] The current transformer is coupled to the power supply line of the device being collected, the output end of the current transformer is connected to the input end of the rectifier unit, the output end of the rectifier unit is connected to the input end of the first voltage divider unit, the output end of the first voltage divider unit is connected to the input end of the first filtering unit, and the output end of the first filtering unit is respectively connected to the controller and the clamping unit.

[0018] In some embodiments of the present invention, the rectifier unit includes a rectifier diode D10, the first voltage divider unit includes a resistor R14 and a resistor R13, the first filter unit includes a resistor R12 and a filter capacitor C8, and the clamping unit includes a clamping diode D102;

[0019] The first end of the coil of the current transformer is connected to the anode of the rectifier diode D10, the second end of the coil of the current transformer is grounded, the cathode of the rectifier diode D10 is connected to the first end of the resistor R14, the second end of the resistor R14 is respectively connected to the first end of the resistor R13 and the first end of the resistor R12, the second end of the resistor R13 is grounded, the second end of the resistor R12 is respectively connected to the controller, the first end of the filter capacitor C8, and the first end of the clamping diode D102, the second end of the filter capacitor C8 is grounded, the second end of the clamping diode D102 is connected to the reference power supply, and the third end of the clamping diode D102 is grounded.

[0020] In some embodiments of the present invention, a bias resistor R6 is further provided between the first and second ends of the coil of the current transformer, the second end of the resistor R14 is further connected to the first end of the capacitor E6, and the second end of the capacitor E6 is grounded.

[0021] In some embodiments of the present invention, a thermostat is connected in series to the power supply circuit of the heating device.

[0022] In some embodiments of the present utility model, the temperature sampling module includes a temperature sensor, a voltage smoothing unit, a second voltage dividing unit and a second filtering unit;

[0023] The first end of the temperature sensor is connected to the input end of the voltage smoothing unit, the second end of the temperature sensor is connected to the power supply, the output end of the voltage smoothing unit is connected to the input end of the second voltage divider unit, the output end of the second voltage divider unit is connected to the input end of the second filtering unit, and the output end of the second filtering unit is connected to the controller.

[0024] In some embodiments of the present invention, the voltage smoothing unit includes a capacitor E1, the second voltage dividing unit includes a resistor R1, and the second filtering unit includes a resistor R2 and a filtering capacitor C1;

[0025] The first end of the capacitor E1 is connected to the first end of the temperature sensor, the second end of the capacitor E1 is grounded, the first end of the resistor R1 is connected to the first end of the capacitor E1, the second end of the resistor R1 is grounded, the first end of the resistor R2 is connected to the first end of the resistor R1, the second end of the resistor R2 is connected to the controller, the first end of the filter capacitor C1 is connected to the second end of the resistor R2, and the second end of the filter capacitor C1 is grounded.

[0026] The second technical problem mentioned above is solved by the following technical solution:

[0027] An electric water heater comprises the electric water heater control circuit provided by any of the aforementioned embodiments of the present utility model. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The present invention will be described in further detail below with reference to the accompanying drawings and embodiments.

[0029] Figure 1 This is a structural block diagram of an electric water heater control circuit provided by the utility model;

[0030] Figure 2 A circuit diagram of a current sampling module provided by the utility model;

[0031] Figure 3 A circuit diagram of a temperature sampling module provided by the utility model;

[0032] Figure 4 This is a flow chart of an electric water heater control method provided by the utility model;

[0033] Figure 5 A schematic structural diagram of an electric water heater provided by the utility model;

[0034] Figure 6 This is a structural schematic diagram of another electric water heater provided by the utility model. DETAILED DESCRIPTION

[0035] To make the technical problems solved by the present invention, the technical solutions adopted, and the technical effects achieved more clearly, the technical solutions of the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings. Obviously, the embodiments described are only some of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work shall fall within the scope of protection of the present invention.

[0036] In the description of this utility model, unless otherwise specified or limited, the terms "connected," "connect," and "fixed" should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection or electrical connection; direct connection or indirect connection through an intermediate medium; internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in this utility model based on the specific circumstances.

[0037] In the present invention, unless otherwise expressly specified and limited, the first feature being "above" or "below" the second feature may include the first and second features being in direct contact, or may include the first and second features being in contact not directly but through another feature between them. Moreover, the first feature being "above", "above" and "above" the second feature includes the first feature being directly above and obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. The first feature being "below", "below" and "below" the second feature includes the first feature being directly below and obliquely below the second feature, or simply means that the first feature is lower in level than the second feature. In addition, the terms "first" and "second" are only used to distinguish in description and have no special meaning.

[0038] Figure 1 This is a structural block diagram of an electric water heater control circuit provided by the utility model, such as Figure 1 As shown, the electric water heater control circuit includes:

[0039] Controller 110;

[0040] The first relay 121 is connected to the controller 110 and is used to control the power on and off of the first working module 210. Exemplarily, the first relay 121 is connected in series in the power supply circuit of the first working module 210. The controller 110 is connected to a control switch in the power supply circuit for the control coil of the first relay 121 to control the power on and off of the power supply circuit for the control coil of the first relay 121. When the control switch is turned on under the control of the controller 110, the control coil of the first relay 121 is energized, the first relay 121 is energized, and the first working module 210 is powered on.

[0041] The second relay 122 is connected to the controller 110 and is used to control the power on and off of the second working module 220. Exemplarily, the second relay 122 is connected in series in the power supply circuit of the second working module 220. The controller 110 is connected to a control switch in the power supply circuit for the control coil of the second relay 122 to control the power on and off of the power supply circuit for the control coil of the second relay 122. When the control switch is turned on under the control of the controller 110, the control coil of the second relay 122 is energized, the second relay 122 is energized, and the second working module 220 is powered on.

[0042] The first current sampling module 131 is connected to the controller 110 and is used to detect the operating current of the first working module 210 and provide feedback to the controller. In the embodiment of the present invention, the first current sampling module 131 can be directly electrically connected to the power supply circuit of the first working module 210 for current sampling, or can be coupled to the power supply circuit of the first working module 210 for current sampling. For example, current sampling can be performed using a current transformer, which is not limited in the embodiment of the present invention.

[0043] The second current sampling module 132 is connected to the controller 110 and is used to detect the operating current of the second working module 220 and feed it back to the controller 110. In the embodiment of the present invention, the second current sampling module 132 can be directly electrically connected to the power supply circuit of the second working module 220 for current sampling, or can be coupled to the power supply circuit of the second working module 220 for current sampling. For example, a current transformer can be used for current sampling, which is not limited in the embodiment of the present invention.

[0044] The temperature sampling module 140 is connected to the controller 110 and is used to detect the temperature of the power bus PL of the electric water heater and feed back the temperature to the controller 110 .

[0045] In one application scenario, the controller 110 is configured to control the first relay 121 and the second relay 122 to be disconnected when the temperature of the power bus PL is greater than a temperature threshold, or when it is detected that both the first working module 210 and the second working module 220 have an operating current. For example, when the controller 110 receives feedback from the temperature sampling module 140 that the temperature is greater than the temperature threshold, the controller 110 controls the first relay 121 and the second relay 122 to be disconnected, thereby avoiding the risk of fire caused by excessive line temperature due to line aging or poor contact, thereby improving safety. When the controller 110 receives a feedback signal from the first current sampling module 131 indicating that the first working module 210 has an operating current, and receives a feedback signal from the second current sampling module 132 indicating that the second working module 220 has an operating current, the controller controls the first relay 121 and the second relay 122 to be disconnected, thereby avoiding the phenomenon of the electric water heater being overloaded due to the simultaneous operation of the two working modules, thereby improving safety.

[0046] In some embodiments, after the controller 110 controls the first relay 121 and the second relay 122 to be disconnected, it may also send a warning message to the user.

[0047] In some embodiments of the present invention, the first working module 210 is a heating tube, and the second working module 220 is a heating device. For example, the electric water heater includes a heating tube and a heating device. The heating tube is arranged in the water tank of the electric water heater and is used to heat the water in the water tank. The heating device can be arranged on the outer wall of the water tank. The heating device can include a fan and a heating wire. When the heating wire is energized, it can heat the surrounding air, and the fan sends the hot air out, thereby increasing the indoor temperature. The heating tube and the heating device are both high-power heating devices and therefore cannot operate at the same time. When the controller 110 receives a feedback signal from the first current sampling module 131 indicating that the heating tube has an operating current, and receives a feedback signal from the second current sampling module 132 indicating that the heating device has an operating current, it controls the first relay 121 and the second relay 122 to be disconnected, thereby avoiding the phenomenon of the electric water heater being overloaded due to the heating tube and the heating device operating at the same time, thereby improving safety.

[0048] In some embodiments of the present invention, the first working module 210 is a first heating tube, and the second working module 220 is a second heating tube. Exemplarily, the electric water heater includes two heating tubes, namely a first heating tube and a second heating tube, and both heating tubes are arranged in the water tank of the electric water heater for heating the water in the water tank. Both heating tubes are high-power heating devices and therefore cannot work at the same time. When the controller 110 receives a feedback signal from the first current sampling module 131 indicating that there is a working current in the first heating tube, and receives a feedback signal from the second current sampling module 132 indicating that there is a working current in the second heating tube, the first relay 121 and the second relay 122 are controlled to be disconnected, so as to avoid the phenomenon that the two heating tubes work at the same time and cause the electric water heater to be overloaded, thereby improving safety.

[0049] In other embodiments of the present invention, the electric water heater includes a heating tube and a warm air device, and the warm air device includes a first heating wire and a second heating wire. The first operating module 210 is the heating tube, and the second operating module 220 is the first heating wire or the second heating wire, that is, the heating tube and the warm air device cannot operate at the same time. The first operating module 210 is the first heating wire, and the second operating module 220 is the second heating wire, that is, the first heating wire and the second heating wire cannot operate at the same time.

[0050] In some embodiments of the present invention, a thermostat is connected in series to the power supply circuit of the heating device. When the line temperature there reaches a preset value, the thermostat automatically disconnects and cuts off the power supply circuit of the heating device. After the temperature there returns to normal, the thermostat closes again and supplies power to the heating device again.

[0051] In some embodiments of the present invention, the first current sampling module and the second current sampling module have the same circuit structure, and are hereinafter collectively referred to as current sampling modules. Figure 2 This is a circuit diagram of a current sampling module provided by the utility model, such as Figure 2 As shown, the current sampling module includes a current transformer CT1 , a rectifier unit 1311 , a first voltage divider unit 1312 , a first filter unit 1313 and a clamping unit 1314 .

[0052] The current transformer CT1 is coupled to the power supply line of the device being collected (the first and second working modules), and its output is connected to the input of the rectifier unit 1311. The current transformer CT1 consists of a closed core and windings. Its primary winding L1 has a few turns and is connected in series with the power supply circuit of the device being collected. Its secondary winding L2 has more turns and is connected to the input of the rectifier unit 1311. The current transformer CT1 converts the high primary current into a low secondary current. The output of the rectifier unit 1311 is connected to the input of the first voltage divider unit, which converts the AC voltage output from the secondary side of the current transformer CT1 into a DC voltage. The output of the first voltage divider unit 1312 is connected to the input of the first filter unit 1313, which divides the voltage output from the rectifier unit 1311 to determine the voltage value sent to the controller 110. The output end VO1 of the first filtering unit 1313 is connected to the controller 110 and the clamping unit 1314 respectively. The first filtering unit 1313 filters the voltage output by the first voltage divider unit 1312, filters out the sharp pulses in the electrical signal output by the first voltage divider unit 1312, and improves the current sampling accuracy. The clamping unit 1314 is connected to a stable reference power supply Vf, and is used to limit the voltage value input to the controller 110 so that it does not exceed the voltage value of the reference power supply, thereby preventing the internal components of the controller from being damaged by high voltage breakdown.

[0053] In some embodiments of the present invention, Figure 2 As shown, the rectifying unit 1311 includes a rectifying diode D10, the first voltage dividing unit 1312 includes a resistor R14 and a resistor R13, the first filtering unit 1313 includes a resistor R12 and a filtering capacitor C8, and the clamping unit 1314 includes a clamping diode D102.

[0054] The first end of the secondary winding L2 of the current transformer CT1 is connected to the anode of a rectifier diode D10. The second end of the secondary winding L2 of the current transformer CT1 is grounded. The cathode of the rectifier diode D10 is connected to the first end of a resistor R14. The rectifier diode D10 performs half-wave rectification on the alternating voltage output by the secondary winding L2. The second end of the resistor R14 is connected to the first end of a resistor R13 and the first end of a resistor R12, respectively. The second end of the resistor R13 is grounded. The voltage input to the controller 110 is the voltage of the resistor R13, that is, the voltage input to the controller 110 is determined by the resistance value of the resistor R13. The second end of the resistor R12 (i.e., VO1) is connected to the controller 110, the first end of the filter capacitor C8, and the first end of the clamping diode D102, respectively. The second end of the filter capacitor C8 is grounded. The resistor R12 and the filter capacitor C8 form an RC filter circuit to filter the voltage output by the first voltage divider unit 1312. The second end of the clamping diode D102 is connected to the reference power supply Vf, and the third end of the clamping diode D102 is grounded. When the voltage output by the first filtering unit 1313 is less than or equal to the reference power supply Vf, the clamping diode D102 is in the cut-off state, and the voltage value input to the controller 110 is the voltage output by the first filtering unit 1313; when the voltage output by the first filtering unit 1313 is greater than the reference power supply Vf, the clamping diode D102 is reversely broken down, the clamping diode D102 is turned on, and the voltage value input to the controller 110 is the voltage value of the reference power supply Vf.

[0055] In some embodiments of the present invention, Figure 2 As shown, a bias resistor R6 is further provided between the first and second ends of the secondary winding L2 of the current transformer CT1 to ensure that the conversion magnetic field within the current transformer CT1 is in a non-saturated state. The second end of the resistor R14 is also connected to the first end of the capacitor E6, and the second end of the capacitor E6 is grounded. The capacitor E6 is used to smooth the voltage waveform output by the rectifier unit 1311.

[0056] Figure 3 A circuit diagram of a temperature sampling module provided by the present invention is shown in FIG. Figure 3 As shown, the temperature sampling module includes a temperature sensor, a voltage smoothing unit 141 , a second voltage dividing unit 142 and a second filtering unit 143 .

[0057] The temperature sensor is connected to the input of the voltage smoothing unit 141 via the first end of the connector CN1, and the second end of the connector CN1 is connected to the power supply VCC. The temperature sensor is used to convert the temperature signal of the power bus into an electrical signal. The output of the voltage smoothing unit 141 is connected to the input of the second voltage divider unit 142, which is used to smooth the waveform of the electrical signal output by the temperature sensor. The output of the second voltage divider unit 142 is connected to the input of the second filtering unit 143, which divides the smoothed electrical signal to determine the voltage value sent to the controller 110. The output VO2 of the second filtering unit 143 is connected to the controller 110, and the second filtering unit 143 filters the voltage output by the second voltage divider unit 142 to remove sharp pulses in the electrical signal output by the second voltage divider unit 142, thereby improving the temperature detection accuracy.

[0058] In some embodiments of the present invention, Figure 3 As shown, the voltage smoothing unit 141 includes a capacitor E1 , the second voltage dividing unit 142 includes a resistor R1 , and the second filtering unit 143 includes a resistor R2 and a filtering capacitor C1 .

[0059] The first end of capacitor E1 is connected to the first end of connector CN1, and the second end of capacitor E1 is grounded. Capacitor E1 is used to smooth the waveform of the electrical signal output by the temperature sensor. The first end of resistor R1 is connected to the first end of capacitor E1, and the second end of resistor R1 is grounded. Resistor R1 and the internal resistance of the temperature sensor form a voltage divider circuit. The voltage input to controller 110 is the voltage of resistor R1, that is, the voltage input to controller 110 is determined by the resistance value of resistor R1. The first end of resistor R2 is connected to the first end of resistor R1, and the second end of resistor R2 (i.e., VO2) is connected to controller 110. The first end of filter capacitor C1 is connected to the second end of resistor R2, and the second end of filter capacitor C1 is grounded. Resistor R2 and filter capacitor C1 form an RC filter circuit to filter out sharp pulses in the electrical signal output by the second voltage divider unit 142.

[0060] The present invention further provides an electric water heater control method, which is applied to the electric water heater control circuit provided by any of the aforementioned embodiments of the present invention and is executed by a controller in the electric water heater control circuit. Figure 4 This is a flow chart of an electric water heater control method provided by the utility model, such as Figure 4 As shown, the electric water heater control method includes:

[0061] S101: Detect the temperature of the power bus of the electric water heater, the operating current of the first working module, and the operating current of the second working module.

[0062] Referring to the electric water heater control circuit provided in the aforementioned embodiment, the temperature sampling module is used to detect the temperature of the power bus of the electric water heater and feed it back to the controller, the first current sampling module is used to detect the working current of the first working module and feed it back to the controller, and the second current sampling module is used to detect the working current of the second working module and feed it back to the controller.

[0063] S102: When the temperature of the power bus is greater than a temperature threshold, or when both the first working module and the second working module have working currents, control the first relay and the second relay to be disconnected.

[0064] For example, when the controller receives feedback from the temperature sampling module that the temperature is greater than a temperature threshold, it controls both the first and second relays to disconnect, thereby avoiding the risk of fire caused by excessive circuit temperature due to circuit aging or poor contact, thereby improving safety. When the controller receives feedback from the first current sampling module indicating that the first working module has an operating current, and receives feedback from the second current sampling module indicating that the second working module has an operating current, it controls both the first and second relays to disconnect, thereby avoiding the phenomenon of the electric water heater being overloaded due to the two working modules operating simultaneously, thereby improving safety.

[0065] The specific structure and working principle of the electric water heater control circuit have been described in detail in the aforementioned embodiments, and will not be repeated here in the embodiments of the present utility model.

[0066] In some embodiments of the present invention, after each power-on reset of the electric water heater, the working current of the first working module and the working current of the second working module are detected. If the first working module or the second working module has a working current, it is determined that the first relay or the second relay is stuck. Specifically, the first relay and the second relay are normally open relays. Each time the electric water heater is powered off, the first relay and the second relay should be disconnected. When the electric water heater is powered on and reset again, in the absence of other actions, the first relay and the second relay should maintain a disconnected state, that is, the first working module and the second working module should have no working current. If the first working module has a working current, it means that the first relay is stuck and was not disconnected during the previous power-off. If the second working module has a working current, it means that the second relay is stuck and was not disconnected during the previous power-off.

[0067] In some embodiments of the present invention, after controlling the first relay and the second relay to be disconnected, the method further includes:

[0068] If the first working module or the second working module still has an operating current, it is determined that the first relay or the second relay is stuck. For example, if the first working module has an operating current, it means that the first relay is stuck and cannot be disconnected normally. If the second working module has an operating current, it means that the second relay is stuck and cannot be disconnected normally.

[0069] If neither the first working module nor the second working module has an operating current, it is determined that the power supply circuit of the electric water heater is aging or the connection terminals are in poor contact. For example, if neither the first working module nor the second working module has an operating current, but the temperature of the power bus of the electric water heater is greater than the temperature threshold, it indicates that the power supply circuit of the electric water heater is aging or the connection terminals are in poor contact, resulting in excessive current in the circuit and causing the power bus temperature to be too high.

[0070] The utility model also provides an electric water heater. Figure 5 This is a schematic diagram of the structure of an electric water heater provided by the utility model, as shown in FIG. Figure 5 As shown, the electric water heater includes a control panel 100, a heating pipe 210 and a warm air device 220. The control panel 100 integrates the electric water heater control circuit provided by any of the above embodiments of the present invention. Figure 5 As shown, the control panel 100 is provided with a controller ( Figure 5 Not shown), the first relay 121, the second relay 122, the first current sampling module ( Figure 5 Not shown), the second current sampling module ( Figure 5 Not shown) and temperature sampling module ( Figure 5 (not shown in the figure), the power bus PL includes a live wire L, a neutral wire N, and a ground wire E. A power plug is provided at the end of the power bus for connecting to an external power source. The live wire L is connected to the first end of the first relay 121 and the second relay 122, respectively. The second end of the first relay 121 is connected to the first end of the heating tube 210 via a wire, and the second end of the heating tube 210 is connected to the neutral wire N. Specifically, the control board 100 is provided with a neutral wire interface, to which the neutral wire N is connected, and the second end of the heating tube 210 is also connected. The second end of the second relay 122 is connected to the first end of the heater 220 via a wire, and the second end of the heater 220 is connected to the neutral wire interface.

[0071] The wire connecting the first relay 121 and the heating tube 210 is connected in series with the primary winding L1 of a current transformer. The secondary winding L2 of this current transformer is connected to the input port of the first current sampling module on the control board 100. The wire connecting the second relay 122 and the heating device 220 is connected in series with the primary winding L1 of a current transformer. The secondary winding L2 of this current transformer is connected to the input port of the second current sampling module on the control board 100.

[0072] The temperature sensor can be arranged inside the package of the power bus to detect the temperature of the power bus of the electric water heater and feed back to the controller.

[0073] For example, Figure 5 As shown, a thermostat 301 is also connected in series to the power bus. When the temperature there reaches a first preset value, the thermostat 301 automatically disconnects and cuts off the power supply of the power bus. After the temperature there returns to normal, the thermostat 301 closes again and the power bus resumes power supply.

[0074] For example, Figure 5 As shown, a thermostat 302 is connected in series in the power supply circuit of the heating device 220. When the temperature there reaches a second preset value, the thermostat 302 is automatically disconnected, cutting off the power supply circuit of the heating device 220. After the temperature there returns to normal, the thermostat 302 is reclosed and power is supplied to the heating device 220 again.

[0075] For example, Figure 5 As shown, the heating device 220 also includes a fan 221, and a relay 123 is also provided on the control board 100. The fan 221 is connected to the control board 100 through a power supply interface, the live wire L is connected to the first end of the relay 123, and the second end of the relay 123 is connected to the power supply interface of the fan 221 through the wiring on the control board 100. When the controller starts the heating device 220, it also starts the fan 221 to send out hot air.

[0076] For example, Figure 5 As shown, the electric water heater also includes a control panel 410, which may include a display and interactive buttons. The control panel 410 may be connected to the control panel 100 via a cable. The user sends instructions to the controller via the interactive buttons to control the operation of the heating tube 210 or the heating device 220.

[0077] For example, Figure 5 As shown, the electric water heater also includes a negative ion module 510, which is connected to the control panel 410 via a cable. The user sends instructions to the controller through interactive buttons to control the operation of the negative ion module 510. The negative ion module 510 is used to ionize the air, generate negative ions, and release them into the indoor space.

[0078] For example, Figure 5 As shown, the heater 220 further includes a swing motor 222, which is connected to the control panel 410 via a cable. The user sends instructions to the controller through interactive buttons to control the swing motor 222, thereby driving the swing mechanism to swing and control the air outlet direction of the heater 220.

[0079] Figure 6 This is a schematic diagram of the structure of another electric water heater provided by the present invention, as shown in FIG. Figure 6 As shown, the electric water heater includes a control panel 100, a first heating tube 211, a second heating tube 212 and a heating device 220, the heating device 220 includes a first heating wire 224 and a second heating wire 225, and the control panel 100 is integrated with the electric water heater control circuit provided by any of the aforementioned embodiments of the present invention. For example, the first heating tube 211, the second heating tube 212, the first heating wire 224 and the second heating wire 225 are respectively provided with corresponding current sampling modules. The control panel 100 is provided with a controller ( Figure 6 Not shown), relay 1211, relay 1212, relay 1221, relay 1222, first current sampling module ( Figure 6 Not shown), the second current sampling module ( Figure 6 Not shown), the third current sampling module ( Figure 6 Not shown), the fourth current sampling module ( Figure 6 Not shown) and temperature sampling module ( Figure 6 The first current sampling module is used to collect the working current of the first heating tube 211, the second current sampling module is used to collect the working current of the second heating tube 212, the third current sampling module is used to collect the working current of the first heating wire 224, and the fourth current sampling module is used to collect the working current of the second heating wire 224.

[0080] The power bus PL includes a live wire L, a neutral wire N, and a ground wire E. A power plug is provided at the end of the power bus for connecting to an external power source. The live wire L is connected to the first ends of relays 1211, 1212, 1221, and 1222, respectively. The second end of relay 1211 is connected to the first end of the first heating tube 211 via a wire, and the second end of the first heating tube 211 is connected to the neutral wire N. Specifically, the control board 100 is provided with a neutral wire interface, to which the neutral wire N is connected, and the second end of the first heating tube 211 is also connected. The second end of relay 1212 is connected to the first end of the second heating tube 212 via a wire, and the second end of the second heating tube 211 is connected to the neutral wire interface. The second end of relay 1221 is connected to the first end of the first heating wire 224 via a wire, and the second end of the first heating wire 224 is connected to the neutral wire interface. The second end of relay 1222 is connected to the first end of the second heating wire 225 via a wire, and the second end of the second heating wire 225 is connected to the neutral wire interface.

[0081] The wire connecting relay 1211 to the first heating tube 211 is connected in series with the primary winding L1 of a current transformer. The secondary winding L2 of this current transformer is connected to the input port of the first current sampling module on the control board 100. The wire connecting relay 1212 to the second heating tube 212 is connected in series with the primary winding L1 of a current transformer. The secondary winding L2 of this current transformer is connected to the input port of the second current sampling module on the control board 100. The wire connecting relay 1221 to the first heating wire 224 is connected in series with the primary winding L1 of a current transformer. The secondary winding L2 of this current transformer is connected to the input port of the third current sampling module on the control board 100. The wire connecting relay 1222 to the second heating wire 225 is connected in series with the primary winding L1 of a current transformer. The secondary winding L2 of this current transformer is connected to the input port of the fourth current sampling module on the control board 100.

[0082] The temperature sensor can be arranged inside the package of the power bus to detect the temperature of the power bus of the electric water heater and feed back to the controller.

[0083] Exemplarily, when the temperature of the power bus is greater than the temperature threshold, or when any two of the first heating tube 211 , the second heating tube 212 , the first heating wire 224 , and the second heating wire 225 have operating currents, all relays are controlled to be disconnected.

[0084] For example, Figure 6 As shown, a thermostat 301 is also connected in series to the power bus. When the temperature there reaches a first preset value, the thermostat 301 automatically disconnects and cuts off the power supply of the power bus. After the temperature there returns to normal, the thermostat 301 closes again and the power bus resumes power supply.

[0085] For example, Figure 6 As shown, the power supply circuits of the first heating wire 224 and the second heating wire 225 are both connected in series with a thermostat 302. When the temperature there reaches a second preset value, the thermostat 302 automatically disconnects, cutting off the power supply circuit of the corresponding heating wire. After the temperature there returns to normal, the thermostat 302 closes again and supplies power to the heating wire again.

[0086] For example, Figure 6 As shown, the heating device 220 also includes a fan 221, and a relay 123 is also provided on the control board 100. The fan 221 is connected to the control board 100 through a power supply interface, the live wire L is connected to the first end of the relay 123, and the second end of the relay 123 is connected to the power supply interface of the fan 221 through the wiring on the control board 100. When the controller starts the heating device 220, it also starts the fan 221 to send out hot air.

[0087] For example, Figure 6 As shown, the electric water heater also includes a control panel 410, which may include a display and interactive buttons. The control panel 410 can be connected to the control board 100 through a cable. The user can send instructions to the controller through the interactive buttons to control the operation of one of the first heating tube 211, the second heating tube 212, the first heating wire 224 and the second heating wire 225.

[0088] For example, Figure 6 As shown, the electric water heater also includes a negative ion module 510, which is connected to the control panel 410 via a cable. The user sends instructions to the controller through interactive buttons to control the operation of the negative ion module 510. The negative ion module 510 is used to ionize the air, generate negative ions, and release them into the indoor space.

[0089] For example, Figure 6 As shown, the heater 220 further includes a swing motor 222, which is connected to the control panel 410 via a cable. The user sends instructions to the controller through interactive buttons to control the swing motor 222, thereby driving the swing mechanism to swing and control the air outlet direction of the heater 220.

[0090] In the description of this article, it should be understood that the terms "up", "down", "left", "right", and other orientations or positional relationships are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of description and simplification of operation, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0091] Throughout this specification, references to terms such as "one embodiment" and "example" indicate that a specific feature, structure, material, or characteristic described in conjunction with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, schematic representations of these terms do not necessarily refer to the same embodiment or example.

[0092] In addition, it should be understood that although this specification is described in terms of implementation methods, not every implementation method contains only one independent technical solution. This narrative method of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

[0093] The technical principles of the present invention have been described above with reference to specific embodiments. These descriptions are intended solely to illustrate the principles of the present invention and should not be construed in any way as limiting the scope of protection of the present invention. Based on the explanations herein, those skilled in the art will be able to devise other specific implementations of the present invention without inventive effort, and such implementations will fall within the scope of protection of the present invention.

Claims

1. An electric water heater control circuit, characterized in that: include: Controller; a first relay, connected to the controller and configured to control power on and off of the first working module; a second relay, connected to the controller, for controlling the on and off of the second working module; a first current sampling module, connected to the controller, configured to detect a working current of the first working module and feed the current back to the controller; a second current sampling module, connected to the controller, for detecting the operating current of the second operating module and feeding back the current to the controller; A temperature sampling module is connected to the controller and is used to detect the temperature of the power bus of the electric water heater and feed it back to the controller.

2. The electric water heater control circuit according to claim 1, characterized in that: The first working module is a heating pipe, and the second working module is a warm air device.

3. The electric water heater control circuit according to claim 1, characterized in that: The first working module is a first heating tube, and the second working module is a second heating tube.

4. The electric water heater control circuit according to claim 1, characterized in that: The first current sampling module and the second current sampling module both include a current transformer, a rectifier unit, a first voltage divider unit, a first filter unit and a clamping unit; The current transformer is coupled to the power supply line of the device being collected, the output end of the current transformer is connected to the input end of the rectifier unit, the output end of the rectifier unit is connected to the input end of the first voltage divider unit, the output end of the first voltage divider unit is connected to the input end of the first filtering unit, and the output end of the first filtering unit is respectively connected to the controller and the clamping unit.

5. The electric water heater control circuit according to claim 4, characterized in that: The rectifier unit includes a rectifier diode D10, the first voltage divider unit includes a resistor R14 and a resistor R13, the first filter unit includes a resistor R12 and a filter capacitor C8, and the clamping unit includes a clamping diode D102; The first end of the coil of the current transformer is connected to the anode of the rectifier diode D10, the second end of the coil of the current transformer is grounded, the cathode of the rectifier diode D10 is connected to the first end of the resistor R14, the second end of the resistor R14 is respectively connected to the first end of the resistor R13 and the first end of the resistor R12, the second end of the resistor R13 is grounded, the second end of the resistor R12 is respectively connected to the controller, the first end of the filter capacitor C8, and the first end of the clamping diode D102, the second end of the filter capacitor C8 is grounded, the second end of the clamping diode D102 is connected to the reference power supply, and the third end of the clamping diode D102 is grounded.

6. The electric water heater control circuit according to claim 5, characterized in that: A bias resistor R6 is further provided between the first end and the second end of the coil of the current transformer. The second end of the resistor R14 is further connected to the first end of the capacitor E6. The second end of the capacitor E6 is grounded.

7. The electric water heater control circuit according to claim 2, characterized in that: A temperature controller is connected in series on the power supply circuit of the heating device.

8. The electric water heater control circuit according to any one of claims 1 to 7, characterized in that: The temperature sampling module includes a temperature sensor, a voltage smoothing unit, a second voltage dividing unit and a second filtering unit; The first end of the temperature sensor is connected to the input end of the voltage smoothing unit, the second end of the temperature sensor is connected to the power supply, the output end of the voltage smoothing unit is connected to the input end of the second voltage divider unit, the output end of the second voltage divider unit is connected to the input end of the second filtering unit, and the output end of the second filtering unit is connected to the controller.

9. The electric water heater control circuit according to claim 8, characterized in that: The voltage smoothing unit includes a capacitor E1, the second voltage dividing unit includes a resistor R1, and the second filtering unit includes a resistor R2 and a filtering capacitor C1; The first end of the capacitor E1 is connected to the first end of the temperature sensor, the second end of the capacitor E1 is grounded, the first end of the resistor R1 is connected to the first end of the capacitor E1, the second end of the resistor R1 is grounded, the first end of the resistor R2 is connected to the first end of the resistor R1, the second end of the resistor R2 is connected to the controller, the first end of the filter capacitor C1 is connected to the second end of the resistor R2, and the second end of the filter capacitor C1 is grounded.

10. An electric water heater, characterized in that: The electric water heater control circuit comprises the electric water heater control circuit as claimed in any one of claims 1 to 9.

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