Fuse state monitoring circuit and method

Abstract

The invention discloses a fuse state monitoring circuit and method, and relates to the technical field of aviation power distribution. According to the invention, the controller monitors the state of the fuse through two methods of collecting voltages at two ends of the fuse, applying discrete magnitude at one end and collecting. When current exists in the power channel, the state of the fuse is judged by adopting a method of collecting voltage at two ends; and when the current does not exist in the power channel, the state of the fuse is judged by adopting a method of applying voltage at one end and collecting the voltage. The fuse is generally used for high-power or high-voltage load protection and important channel protection in a power grid. By monitoring the state of the fuse, the state of the whole power grid can be known more accurately, more reliable power supply conversion is made, and the safety of the system is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of aviation power distribution systems, and in particular relates to a fuse state monitoring circuit and method. Background Art

[0002] In the field of aviation power distribution systems, fuses are mainly used to protect the aircraft's main power grid and loads. With the increase in load power, aircraft power supply voltage, and safety requirements, more and more fuses are being used. Fuses are generally used to protect high-power or high-voltage loads. Monitoring the status of load fuses can enable the controller to make timely adjustments to the entire aircraft load more quickly. Fuses are generally used to protect important lines in the power grid. Monitoring the status of power grid fuses can enable the controller to perform power grid switching and fault isolation more quickly. In the prior art, CN210347903U "A Fuse State Monitoring Circuit" discloses a fuse state monitoring circuit, including a current sensor, a fuse, a current acquisition circuit, a low voltage acquisition circuit, a high voltage acquisition circuit, a small signal conversion and digital-to-analog conversion circuit, a single-chip microcomputer and peripheral circuits and a working power supply circuit. The utility model can monitor abnormal conditions before the fuse fails and disconnects, and issue a warning prompt. If it is replaced or processed in time, the risk of sudden power outages of equipment or machines can be prevented, and it can also realize the monitoring of loop current and the monitoring of system voltage under fault conditions, providing effective data for the entire system.

[0003] There are generally two methods for monitoring the status of fuses in current technology: an off-site monitoring method, which removes the fuse from the product for testing; and a two-terminal voltage monitoring method, which detects the voltage at both ends of the fuse to determine the status of the fuse.

[0004] The off-site inspection and monitoring method is only applicable to the regular power-off maintenance of the power distribution system, which affects the operation and use of the aircraft. The two-terminal voltage detection method is only applicable when there is power in the channel where the fuse is located. If there is no current in the channel, detection cannot be performed.

[0005] Therefore, it is necessary to design a simple fuse status detection circuit for the airborne power distribution system. Summary of the invention

[0006] In order to solve the above-mentioned deficiencies in the prior art, the present invention provides a method for monitoring the fuse status when there is current in the channel or not. By monitoring the fuse status, the power grid status can be more specifically perceived, so that more timely and accurate actions can be taken, thereby improving the safety and reliability of the system.

[0007] In view of this, according to one aspect of an embodiment of the present invention, a fuse state monitoring circuit is provided, comprising: a power supply 1, a fuse 2, a load 3, a switching relay 4, a resistor 5, and a controller 6; wherein the a port of the fuse 2 is respectively connected to the D2 port of the switching relay 4 and the power supply 1, the b port of the fuse 2 is connected to the C2 port of the switching relay 4 and the load 3, the e port of the controller 6 is connected to the C3 port of the switching relay 4, the f port of the controller 6 is connected to the D3 port of the switching relay 4 and the c port of the resistor 5, the g port of the controller 6 is connected to the X1+ port of the switching relay 4 and the d port of the resistor 5, the D1 port of the switching relay 4 is connected to the c port of the resistor 5, and the C1 port and X2- port of the switching relay 4 are both grounded.

[0008] Optionally, when the X1+ port of the conversion relay 4 is unloaded, the C2 port and the C3 port of the conversion relay 4 are connected, and the D2 port and the D3 port are connected; when the X1+ port of the conversion relay 4 is connected, the conversion relay 4 is actuated, the C2 port and the C1 port of the conversion relay 4 are connected, and the D2 port and the D1 port are connected, the e port and the f port of the controller 6 are voltage acquisition ports, and the g port is an excitation output port.

[0009] Optionally, when the X1+ port of the switching relay 4 is unloaded, a fuse power-on status acquisition circuit is formed, and the e port of the controller 6 collects the b-end voltage of the fuse 2 through the C3 port and C2 port of the switching relay 4, and the f port of the controller 6 collects the a-end voltage of the fuse 2 through the D3 port and D2 port of the switching relay 4.

[0010] Optionally, when the X1+ port of the switching relay 4 is turned on, the switching relay 4 operates to form a fuse power-off state acquisition circuit, the e port of the controller 6 is suspended, the f port of the controller 6 acquires the c port voltage of the resistor 5, and the g port of the controller 6 applies excitation to the X1+ port of the switching relay 4 and to the a port of the fuse 2 through the resistor 5.

[0011] Optionally, the g port of the controller 6 outputs a high-level signal or an open-circuit signal. The high-level signal should be lower than 10 VDC. This port can be used to stimulate the fuse 2 and stimulate the switching relay 4 to operate.

[0012] Optionally, the resistance of the resistor 5 is greater than 1 KΩ.

[0013] Optionally, the rated excitation voltage value of the X1+ port of the conversion relay 4 is consistent with the voltage value of the g port excitation output port of the controller 5 .

[0014] According to another aspect of the embodiment of the present invention, a fuse status monitoring method is also provided, characterized in that, using any of the above-mentioned circuits, the e port and the f port of the controller 6 collect the voltage of the a port and the b port of the fuse 2 through the conversion relay 4, and when there is voltage at both ports, it is judged that the fuse 2 is turned on; when there is voltage at only one of the ports, it is judged that the fuse 2 is turned off; when there is no voltage at both ports of the fuse 2, the g port of the controller 6 outputs excitation to control the action of the conversion relay 4, the conversion relay 4 applies excitation to the a end of the fuse 2, and the f port of the controller 6 collects voltage, and when the f port of the controller 6 collects a low-level voltage, it is judged that the fuse 2 is turned on; when a high-level voltage is collected, it is judged that the fuse 2 is turned off.

[0015] Optionally, the output signal of the excitation output port of the controller 6 changes from an open-circuit signal to a high-level signal. After a preset time, the controller 6 determines the state of the fuse 2 based on the collected voltage at the c-port of the resistor 5 .

[0016] The present invention is applied in the field of aviation power distribution, and the fuse status monitoring can be completed by adding a switching relay and three ports of the controller. The circuit does not need to add components on a large scale, but can effectively enhance the safety of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a simplified diagram of the fuse status monitoring circuit;

[0018] Description of reference numerals:

[0019] 1-power supply, 2-fuse, 3-load, 4-changeover relay, 5-resistance, 6-controller. DETAILED DESCRIPTION

[0020] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0021] According to one aspect of an embodiment of the present invention, a fuse status monitoring circuit is provided, such as Figure 1As shown, it includes: a power supply 1, a fuse 2, a load 3, a conversion relay 4, a resistor 5, and a controller 6; wherein the a port of the fuse 2 is connected to the D2 port of the conversion relay 4 and the power supply 1 respectively, the b port of the fuse 2 is connected to the C2 port of the conversion relay 4 and the load 3, the e port of the controller 6 is connected to the C3 port of the conversion relay 4, the f port of the controller 6 is connected to the D3 port of the conversion relay 4 and the c port of the resistor 5, the g port of the controller 6 is connected to the X1+ port of the conversion relay 4 and the d port of the resistor 5, the D1 port of the conversion relay 4 is connected to the c port of the resistor 5, and the C1 port and X2- port of the conversion relay 4 are both grounded.

[0022] Further, when the X1+ port of the conversion relay 4 is unloaded, the C2 port and the C3 port of the conversion relay 4 are connected, and the D2 port and the D3 port are connected; when the X1+ port of the conversion relay 4 is connected, the conversion relay 4 is actuated, the C2 port and the C1 port of the conversion relay 4 are connected, and the D2 port and the D1 port are connected, the e port and the f port of the controller 6 are voltage acquisition ports, and the g port is an excitation output port.

[0023] Furthermore, when the X1+ port of the switching relay 4 is unloaded, a fuse power-on status acquisition circuit is formed, and the e port of the controller 6 collects the b-end voltage of the fuse 2 through the C3 port and C2 port of the switching relay 4, and the f port of the controller 6 collects the a-end voltage of the fuse 2 through the D3 port and D2 port of the switching relay 4.

[0024] Furthermore, when the X1+ port of the switching relay 4 is turned on, the switching relay 4 operates to form a fuse power-off state acquisition circuit, the e port of the controller 6 is suspended, the f port of the controller 6 acquires the c port voltage of the resistor 5, and the g port of the controller 6 applies excitation to the X1+ port of the switching relay 4 and to the a port of the fuse 2 through the resistor 5.

[0025] Furthermore, the g port of the controller 6 outputs a high level signal or an open circuit signal, and the high level signal should be lower than 10VDC. This port can be used to excite the fuse 2 and the switching relay 4. An excitation voltage higher than 10VDC has a greater impact on the load.

[0026] Furthermore, the resistance of the resistor 5 is greater than 1KΩ. A larger resistance of the resistor 5 can make the excitation voltage distributed on the resistor 5 larger and the excitation voltage distributed on the load smaller, which has less impact on the load.

[0027] Furthermore, the rated excitation voltage value of the X1+ port of the switching relay 4 is consistent with the excitation output port voltage value of the g port of the controller 5. This can reduce the number of ports, simplify the circuit, and simplify the control logic.

[0028] According to another aspect of the embodiment of the present invention, a fuse status monitoring method is also provided, characterized in that, using any of the above-mentioned circuits, the e port and the f port of the controller 6 collect the voltage of the a port and the b port of the fuse 2 through the conversion relay 4, and when there is voltage at both ports, it is judged that the fuse 2 is turned on; when there is voltage at only one of the ports, it is judged that the fuse 2 is turned off; when there is no voltage at both ports of the fuse 2, the g port of the controller 6 outputs excitation to control the action of the conversion relay 4, the conversion relay 4 applies excitation to the a end of the fuse 2, and the f port of the controller 6 collects voltage, and when the f port of the controller 6 collects a low-level voltage, it is judged that the fuse 2 is turned on; when a high-level voltage is collected, it is judged that the fuse 2 is turned off.

[0029] Furthermore, the output signal of the excitation output port of the controller 6 changes from an open-circuit signal to a high-level signal. After a preset time, the controller 6 determines the state of the fuse 2 based on the collected voltage at the c-port of the resistor 5 .

[0030] Example

[0031] First, the g port of the controller (6) is open. The e port and the f port of the controller (6) first collect the voltage of the a port and the b port of the fuse (2) through the conversion relay (4).

[0032] When voltage exists at both ends, it is judged that the fuse (2) is intact; when voltage exists at one end and no voltage exists at the other end, it is judged that the fuse (2) is blown.

[0033] When there is no voltage at both ends of the fuse (2), the fuse state cannot be determined. The controller operates further. The g port of the controller (6) outputs +5VDC excitation, controls the operation of the switching relay (4), and then applies +5VDC excitation to the a end of the fuse (2) through the switching relay (4). The f port of the controller (6) collects the voltage of the c port of the resistor (5). When the f port of the controller (6) collects the ground level voltage, it is determined that the fuse is intact; when the high level voltage is collected, it is determined that the fuse is blown.

[0034] The above is only a specific embodiment of the present invention, and the present invention is described in detail. The unexplained part is a conventional technology. However, the protection scope of the present invention is not limited to this. Any changes or substitutions that can be easily thought of by any technician familiar with the technical field within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. The protection scope of the present invention shall be based on the protection scope of the claims.

Claims

1. A fuse status monitoring circuit, characterized in that: include: A power supply (1), a fuse (2), a load (3), a conversion relay (4), a resistor (5), and a controller (6); wherein the a port of the fuse (2) is connected to the D2 port of the conversion relay (4) and the power supply (1) respectively, the b port of the fuse (2) is connected to the C2 port of the conversion relay (4) and the load (3), the e port of the controller (6) is connected to the C3 port of the conversion relay (4), the f port of the controller (6) is connected to the D3 port of the conversion relay (4) and the c port of the resistor (5), the g port of the controller (6) is connected to the X1+ port of the conversion relay (4) and the d port of the resistor (5), the D1 port of the conversion relay (4) is connected to the c port of the resistor (5), and the C1 port and X2- port of the conversion relay (4) are both grounded.

2. The circuit according to claim 1, characterized in that When the X1+ port of the conversion relay (4) is unloaded, the C2 port of the conversion relay (4) is connected to the C3 port, and the D2 port is connected to the D3 port; when the X1+ port of the conversion relay (4) is connected, the conversion relay (4) is actuated, the C2 port of the conversion relay (4) is connected to the C1 port, and the D2 port is connected to the D1 port, the e port and the f port of the controller (6) are voltage acquisition ports, and the g port is an excitation output port.

3. The circuit according to claim 2, characterized in that When the X1+ port of the switching relay (4) is unloaded, a fuse power-on state acquisition circuit is formed, and the e port of the controller (6) acquires the voltage at the b end of the fuse (2) through the C3 port and the C2 port of the switching relay (4), and the f port of the controller (6) acquires the voltage at the a end of the fuse (2) through the D3 port and the D2 port of the switching relay (4).

4. The circuit according to claim 2, characterized in that When the X1+ port of the switching relay (4) is turned on, the switching relay (4) operates to form a fuse power-off state acquisition circuit, the e port of the controller (6) is suspended, the f port of the controller (6) acquires the voltage of the c port of the resistor (5), and the g port of the controller (6) applies excitation to the X1+ port of the switching relay (4) and to the a port of the fuse (2) through the resistor (5).

5. The circuit according to claim 1, characterized in that The g port of the controller (6) outputs a high-level signal or an open-circuit signal. The high-level signal should be lower than 10VDC. This port can be used to stimulate the fuse (2) and stimulate the switching relay (4) to operate.

6. The circuit according to claim 1, characterized in that The resistance value of the resistor (5) is greater than 1KΩ.

7. The circuit according to claim 1, characterized in that The rated excitation voltage value of the X1+ port of the conversion relay (4) is consistent with the voltage value of the g port excitation output port of the controller (5).

8. A method for monitoring fuse status, characterized in that: Using any circuit as described in claims 1 to 7, the e port and the f port of the controller (6) collect the voltage of the a port and the b port of the fuse (2) through the conversion relay (4); when voltage exists at both ports, the fuse (2) is judged to be turned on; when voltage exists at only one of the ports, the fuse (2) is judged to be turned off; when voltage does not exist at both ports of the fuse (2), the g port of the controller (6) outputs excitation to control the action of the conversion relay (4); the conversion relay (4) applies excitation to the a terminal of the fuse (2), and the f port of the controller (6) collects voltage; when the f port of the controller (6) collects a low-level voltage, the fuse (2) is judged to be turned on; when a high-level voltage is collected, the fuse (2) is judged to be turned off.

9. The method according to claim 8, characterized in that The output signal of the excitation output port of the controller (6) changes from an open-circuit signal to a high-level signal. After a preset time, the controller (6) determines the state of the fuse (2) based on the collected voltage at the C port of the resistor (5).

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