Detection device and detection method for charging pile

Abstract

The application provides a detection device and method for a charging pile. The charging pile comprises a first power line, a second power line, a first output end, a second output end and a relay. The second output end is connected to the second power line. The relay is connected between the first power line and the first output end. The detection device comprises a virtual load circuit, a detection circuit and a controller. The controller turns on the relay and controls the virtual load circuit to form a virtual load path, controls the detection circuit to generate a test current, and times the length of time for which the test current is generated. The controller turns off the relay according to the test current to stop generating the test current and generates a timing value, and judges the aging condition of the relay according to the timing value.

Description

Technical Field

[0001] This invention relates to a detection device and a detection method, and particularly to a detection device and a detection method for charging piles. Background Technology

[0002] Generally, a charging station includes a first power line, a second power line, a first output terminal, a second output terminal, and a relay. The second output terminal is connected to the second power line. The relay is connected between the first power line and the first output terminal. The first and second output terminals are connected to the charging gun. The charging station disconnects the relay in response to an abnormality in the charging station. An abnormality in the charging station could be, for example, a leakage current from the first power line. Therefore, the tripping of the relay can interrupt the leakage current from the first power line. The risk of electric shock to the user can be reduced.

[0003] However, over time, relays gradually age. This leads to a longer tripping response time, making it impossible for leakage current from the primary power line to be blocked by the relay in a timely manner. Therefore, the risk of electric shock to users may increase. Thus, it is necessary to perform regular inspections of the relays. Summary of the Invention

[0004] This invention provides a testing device and method for charging piles, capable of detecting the relays in charging piles.

[0005] In one embodiment of the present invention, the detection device is applicable to a charging pile. The charging pile includes a first power line, a second power line, a first output terminal, a second output terminal, and a relay. The second output terminal is connected to the second power line. The first terminal of the relay is connected to the first power line. The second terminal of the relay is connected to the first output terminal. The detection device includes a virtual load circuit, a detection circuit, and a controller. The virtual load circuit is connected between the second output terminal and the second terminal of the relay. The detection circuit is connected to the first power line and the second power line. The controller is connected to the relay, the virtual load circuit, and the detection circuit. The controller turns on the relay and controls the virtual load circuit to form a virtual load path between the second output terminal and the second terminal of the relay, controls the detection circuit to generate a test current between the first power line and the second power line, and times the duration for which the test current is generated. The controller disconnects the relay based on the test current to stop generating the test current, ends the timing to generate a timing value, and determines the aging condition of the relay based on the timing value.

[0006] In one embodiment of the present invention, the detection method is applicable to a charging pile. The charging pile includes a first power line, a second power line, a first output terminal, a second output terminal, and a relay. The second output terminal is connected to the second power line. The first terminal of the relay is connected to the first power line. The second terminal of the relay is connected to the first output terminal. The detection method includes: providing a virtual load circuit and a detection circuit, wherein the virtual load circuit is connected between the second output terminal and the second terminal of the relay, and wherein the detection circuit is connected to the first power line and the second power line; turning on the relay and controlling the virtual load circuit to form a virtual load path between the second output terminal and the second terminal of the relay; controlling the detection circuit to generate a test current between the first power line and the second power line, and timing the duration for which the test current is generated; turning off the relay based on the test current to stop generating the test current, and ending the timing duration to generate a timing value; and determining the aging condition of the relay based on the timing value.

[0007] Based on the above, the detection device and method generate a timing value according to the duration of the test current being generated. This timing value is related to the time taken for the relay to trip. In this way, the detection device and method can determine the aging condition of the relay based on the timing value. Attached Figure Description

[0008] Figure 1 This is a schematic diagram of a charging pile and a detection device according to an embodiment of the present invention.

[0009] Figure 2 This is a flowchart illustrating a detection method according to an embodiment of the present invention.

[0010] Figure 3 This is a schematic diagram of a charging pile and a detection device according to an embodiment of the present invention.

[0011] Figure 4 This is a schematic diagram of a programmable resistor circuit and a test switch according to an embodiment of the present invention.

[0012] Figure 5 This is a flowchart illustrating a detection method according to an embodiment of the present invention.

[0013] Explanation of reference numerals in the attached figures:

[0014] 10: Charging stations

[0015] 100, 200: Detection device

[0016] 110, 210: Virtual load circuit

[0017] 120, 220: Detection circuit

[0018] 130, 230: Controller

[0019] 211: Virtual Load

[0020] 212: Load switch

[0021] 221: Programmable Resistor Circuit

[0022] 222: Test switch

[0023] 240, 250: Current detectors

[0024] 241, 251: Current coupling elements

[0025] 242, 252: Detection circuit

[0026] 260: Voltage sensor

[0027] CV: Timing Value

[0028] ILT: Test Current

[0029] L1: First power line

[0030] L2: Second power line

[0031] P1: First output terminal

[0032] P2: Second output terminal

[0033] PL: Virtual Load Path

[0034] R1~Rn: Resistors

[0035] RL1, RL2: Relays

[0036] RP1~RPn: Programmable resistors

[0037] S100, S200: Detection methods

[0038] S110~S150, S201~S212: Steps

[0039] SC1, SC2, SC3, SC4, SC5: Control signals

[0040] SCV: Set current value

[0041] SS1: Current detection signal

[0042] SS2: Sensing signal

[0043] SS3: Voltage sensing signal

[0044] SV: Setting value Detailed Implementation

[0045] Some embodiments of the present invention will now be described in detail with reference to the accompanying drawings. Component symbols used in the following description, when appearing in different drawings, are considered to be the same or similar components. These embodiments are only a part of the present invention and do not disclose all possible implementations of the invention. More precisely, these embodiments are merely examples within the scope of the present invention's patent application.

[0046] Please refer to Figure 1 , Figure 1 This is a schematic diagram of a charging pile and a detection device according to an embodiment of the present invention. In one embodiment, the detection device 100 is adapted to a charging pile 10. The charging pile 10 includes a first power line L1, a second power line L2, a first output terminal P1, a second output terminal P2, and relays RL1 and RL2. The first power line L1 and the second power line L2 are used to transmit power. The first output terminal P1 and the second output terminal P2 are connected to a charging gun (not shown). The second output terminal P2 is connected to the second power line L2. The first terminal of the relay RL1 is connected to the first power line L1. The second terminal of the relay RL1 is connected to the first output terminal P1. The first terminal of the relay RL2 is connected to the second power line L2. The second terminal of the relay RL2 is connected to the second output terminal P2.

[0047] In one embodiment, the detection device 100 includes a virtual load circuit 110, a detection circuit 120, and a controller 130. The virtual load circuit 110 is connected between a first output terminal P1 and a second output terminal P2. In other words, the virtual load circuit 110 is connected between the second terminal of relay RL1 and the second terminal of relay RL2. The detection circuit 120 is connected to a first power line L1 and a second power line L2.

[0048] In one embodiment, controller 130 is connected to relays RL1 and RL2, virtual load circuit 110, and detection circuit 120. Controller 130 turns on relays RL1 and RL2 and controls virtual load circuit 110 to form a virtual load path PL between the first output terminal P1 (i.e., the second terminal of relay RL1) and the second output terminal P2 (i.e., the second terminal of relay RL2), and controls detection circuit 120 to generate a test current ILT between the first power line L1 and the second power line L2. Furthermore, controller 130 times the duration for which the test current ILT is generated. Based on the generation of the test current ILT, controller 130 turns off relays RL1 and RL2 to stop generating the test current ILT and ends the timing to generate a timing value CV.

[0049] In one embodiment, the test current ILT between the first power line L1 and the second power line L2 can simulate the leakage current occurring on the first power line L1 or the second power line L2.

[0050] In one embodiment, in response to relays RL1 and RL2 tripping (i.e., being disconnected), the virtual load path PL is disconnected. A timing value CV is generated. That is, the timing value CV reflects the length of time it takes for relays RL1 and RL2 to trip when the test current ILT is generated. Next, the controller 130 can determine the aging condition of relays RL1 and RL2 based on the timing value CV.

[0051] It is worth mentioning that the detection device 100 generates a timing value CV based on the duration of the test current ILT. The timing value CV is related to the duration of time it takes for relays RL1 and RL2 to trip when the test current ILT is generated. In this way, the detection device 100 can determine the aging condition of relays RL1 and RL2 based on the timing value CV.

[0052] In one embodiment, controller 130 may use control signal SC1 to control relay RL1. Controller 130 may use control signal SC2 to control relay RL2. Controller 130 may use control signal SC3 to control dummy load circuit 110. Controller 130 may use control signal SC4 to control detection circuit 120 to provide test current ILT.

[0053] In one embodiment, "aging" refers to a state in which the components in relays RL1 and RL2 deteriorate, causing a delay in the tripping of relays RL1 and RL2. Controller 130 determines whether at least one of relays RL1 and RL2 is aged based on a comparison between a timing value CV and a set value SV. If the timing value CV is greater than the set value SV, controller 130 determines that at least one of relays RL1 and RL2 is aged. If the timing value CV is less than or equal to the set value SV, controller 130 determines that at least one of relays RL1 and RL2 is not yet aged.

[0054] In some embodiments, the controller 130 may disconnect one of relays RL1 and RL2 based on the test current ILT to stop generating the test current ILT. For example, the controller 130 disconnects relay RL1 based on the generation of the test current ILT. Therefore, the timing value CV is associated with the length of time it takes for relay RL1 to trip when the test current ILT is generated. The detection device 100 can determine the aging condition of relay RL1. As another example, the controller 130 disconnects relay RL2 based on the generation of the test current ILT. Therefore, the timing value CV is associated with the length of time it takes for relay RL2 to trip when the test current ILT is generated. The detection device 100 can determine the aging condition of relay RL2.

[0055] In one embodiment, relays RL1 and RL2 are implemented, for example, by electromagnetic relays, solid-state relays, thermal relays, or photoresistive relays. Controller 130 is, for example, a central processing unit (CPU), or other programmable general-purpose or special-purpose microprocessor, digital signal processor (DSP), programmable controller, application-specific integrated circuit (ASIC), programmable logic device (PLD), or other similar device or combination thereof.

[0056] In some embodiments, the charging station 10 does not include a relay RL2. Therefore, a virtual load circuit 110 is connected between the second terminal of relay RL1 and the second output terminal P2. The controller 130 disconnects relay RL1 based on the generation of a test current ILT. Therefore, the timing value CV is associated with the length of time it takes for relay RL1 to trip when the test current ILT is generated. In some embodiments, the charging station 10 does not include a relay RL1. Therefore, a virtual load circuit 110 is connected between the second terminal of relay RL2 and the first output terminal P1. The controller 130 disconnects relay RL2 based on the generation of a test current ILT. Therefore, the timing value CV is associated with the length of time it takes for relay RL2 to trip when the test current ILT is generated.

[0057] Please refer to Figure 1 as well as Figure 2 , Figure 2 This is a flowchart illustrating a detection method according to an embodiment of the present invention. In one embodiment, detection method S110 is applicable to a charging pile 10. Detection method S100 is applicable to detecting relays RL1 and RL2 of the charging pile 10. Detection method S100 includes steps S110 to S150. In step S110, a virtual load circuit 110 and a detection circuit 120 are provided. The virtual load circuit 110 is connected between a first output terminal P1 (i.e., at the second terminal of relay RL1) and a second output terminal P2 (i.e., at the second terminal of relay RL2). In other words, the virtual load circuit 110 is connected between the second terminal of relay RL1 and the second terminal of relay RL2. The detection circuit 120 is connected to a first power line L1 and a second power line L2.

[0058] In step S120, the controller 130 turns on relays RL1 and RL2 and controls the virtual load circuit 110 to form a virtual load path PL between the first output terminal P1 and the second output terminal P2. In step S130, the controller 130 controls the detection circuit 120 to generate a test current ILT between the first power line L1 and the second power line L2, and times the duration of the generated test current ILT. In step S140, the controller 130 turns off relays RL1 and RL2 based on the generation of the test current ILT to stop generating the test current ILT, and ends the timing to generate a timing value CV. In step S150, the controller 130 determines the aging condition of relays RL1 and RL2 based on the timing value CV.

[0059] In some embodiments, in step S140, the controller 130 disconnects relay RL1 to stop generating the test current ILT and ends the timing period to generate a timing value CV. In step S150, the controller 130 determines the aging condition of relay RL1 based on the timing value CV. In some embodiments, in step S140, the controller 130 disconnects relay RL2 to stop generating the test current ILT and ends the timing period to generate a timing value CV. In step S150, the controller 130 determines the aging condition of relay RL2 based on the timing value CV.

[0060] Please refer to Figure 3 , Figure 3 This is a schematic diagram of a charging pile and a detection device according to an embodiment of the present invention. In one embodiment, the detection device 200 is applicable to a charging pile 10. The detection device 200 includes a virtual load circuit 210, a detection circuit 220, a controller 230, and current detectors 240 and 250. The virtual load circuit 210 includes a virtual load 211 and a load switch 212. The load switch 212 and the virtual load 211 are connected in series between a first output terminal P1 (i.e., the second terminal of relay RL1) and a second output terminal P2 (i.e., the second terminal of relay RL2). In one embodiment, the first terminal of the load switch 212 is connected to the first output terminal P1. The virtual load 211 is connected between the second terminal of the load switch 212 and the second output terminal P2. The virtual load 211 is, for example, a resistor used as a load, but the present invention is not limited thereto. The controller 230 is connected to the control terminal of the load switch 212. The controller 230 turns on relays RL1 and RL2 and the load switch 212 to form a virtual load path PL.

[0061] In one embodiment, a current detector 240 is connected to a controller 230. The current detector 240 generates a current detection signal SS1 in response to a test current ILT. The controller 230 receives the current detection signal SS1 from the current detector 240. The controller 230 times the duration for which the test current ILT is generated based on the current detection signal SS1 and provides control signals SC1 and SC2. Relay RL1 is deactivated according to control signal SC1. Relay RL2 is deactivated according to control signal SC2.

[0062] A current detector 250 is connected to a controller 230. The current detector 250 senses a test current ILT flowing through one of the first power line L1 and the second power line L2 to generate a sensing signal SS2, and provides the sensing signal SS2 to the controller 230. In response to the sensing signal SS2 indicating that the current value of the test current ILT is equal to 0, the controller 230 stops timing based on the sensing signal SS2 to generate a timing value CV.

[0063] In one embodiment, the current detector 240 includes a current coupling element 241 and a detection circuit 242. The current coupling element 241 detects, for example, the current located on a first power line L1 and a second power line L2 to generate a coupling current. The value of the coupling current is positively correlated with the value of the test current ILT. The detection circuit 242 is connected to the current coupling element 241. The detection circuit 242 generates a current detection signal SS1 based on the coupling current.

[0064] In one embodiment, the current detector 250 includes a current coupling element 251 and a detection circuit 252. The current coupling element 251 detects, for example, the current in the first power line L1 to generate a coupling current. The value of the coupling current is positively correlated with the value of the test current ILT. The detection circuit 252 is connected to the current coupling element 251. The detection circuit 252 generates a sensing signal SS2 based on the coupling current.

[0065] In one embodiment, the detection circuit 220 includes a programmable resistor circuit 221 and a test switch 222. The test switch 222 and the programmable resistor circuit 221 are connected in series between the first power line L1 and the second power line L2. During the period when the virtual load path PL is provided, the controller 230 turns on the test switch 222 and adjusts the resistance value of the programmable resistor circuit 221 so that the current value of the test current ILT reaches the set current value SCV. In one embodiment, the controller 230 can turn on the test switch 222 using the control signal SC4 and set the resistance value of the programmable resistor circuit 221 using the control signal SC5.

[0066] In one embodiment, the detection device 200 further includes a voltage sensor 260. The voltage sensor 260 senses the voltage value located on the first power line L1 to generate a voltage sensing signal SS3. The controller 230 adjusts the resistance value of the programmable resistor circuit 221 based on the voltage sensing signal SS3 and a set current value SCV to bring the current value of the test current ILT to the set current value SCV. Therefore, the controller 230 can maintain the current value of the test current ILT at the set current value SCV based on the voltage sensing signal SS3.

[0067] For example, the voltage difference between the first power line L1 and the second power line L2 is approximately 120 volts. The minimum human body impedance is approximately 500 ohms (Ω). The set current value SCV is approximately 264 milliamperes (i.e., SCV = 120 × 1.1 ÷ 500). This is based on the test specifications for relays RL1 and RL2. The set value SV is, for example, 25 milliseconds. That is, based on a test current ILT of 264 milliamperes, relays RL1 and RL2 must trip within 25 milliseconds after the test current ILT is generated. If tripping occurs within 25 milliseconds after the test current ILT is generated, the test of relays RL1 and RL2 is considered passed. If tripping occurs after 25 milliseconds after the test current ILT is generated, the test of at least one of relays RL1 and RL2 is considered failed.

[0068] In one embodiment, the load switch 212 and the test switch 222 are implemented by any type of relay or at least a transistor switch.

[0069] It should be understood that the detection device 200 is also capable of performing the detection method S100.

[0070] Please refer to Figure 4 , Figure 4 This is a schematic diagram of a programmable resistor circuit and a test switch according to an embodiment of the present invention. In one embodiment, the first terminal of the test switch 222 is connected to a first power line L1, for example, via resistors R1 to Rn. The programmable resistor circuit 221 is connected between the second terminal of the test switch 222 and the second power line L2. The programmable resistor circuit 221 includes programmable resistors RP1 to RPn. The programmable resistors RP1 to RPn are connected in series with each other. The controller 230 can control the resistance value of at least one of the programmable resistors RP1 to RPn. For example, the controller 230 provides a control signal SC5 to the programmable resistor circuit 221 via an I2C interface to adjust the resistance value of at least one of the programmable resistors RP1 to RPn using the control signal SC5.

[0071] Please refer to Figure 2 as well as Figure 5 , Figure 5 This is a flowchart illustrating a detection method according to an embodiment of the present invention. In one embodiment, detection method S200 is applicable to detecting relays RL1 and RL2 of a charging pile 10. Detection method S200 includes steps S201 to S212. In step S201, the charging pile 10 is activated. Therefore, the first power line L1 and the second power line L2 receive power. In step S202, the controller 230 turns on relays RL1 and RL2 and the test switch 222. In step S203, the controller 230 determines whether current flows through the virtual load path PL. In response to no current flowing through the virtual load path PL, the controller 230 determines that at least one of relays RL1 and RL2 and the test switch 222 is not properly turned on, thereby preventing the virtual load path PL from transmitting power. Therefore, the controller 230 determines in step S204 that at least one of relays RL1 and RL2 and the test switch 222 is malfunctioning and provides a warning signal. On the other hand, in response to current flowing through the virtual load path PL, controller 230 adjusts the resistance value of programmable resistor circuit 221 in step S205. In one embodiment, controller 230 may detect the voltage value of the power supply via the first power line L1 and obtain a target resistance value based on the power supply voltage value and a set current value SCV. Controller 230 adjusts the resistance value of programmable resistor circuit 221 based on the target resistance value.

[0072] In one embodiment, the controller 230 subtracts the sum of the resistance values ​​of resistors R1 to Rn from the target resistance value to generate the aforementioned resistance difference, and adjusts the resistance value of the programmable resistor circuit 221 to the aforementioned resistance difference.

[0073] by Figure 4 For example, the controller 230 subtracts the sum of the resistance values ​​of resistors R1 to Rn and the virtual load 211 from the target resistance value to generate the aforementioned resistance difference, and adjusts the resistance value of the programmable resistor circuit 221 to the aforementioned resistance difference.

[0074] In step S206, the controller 230 turns on the test switch 222. Therefore, a test current ILT with a set current value SCV is generated. The current detector 240 begins sensing the test current ILT.

[0075] In step S207, the controller 230 determines whether relays RL1 and RL2 are disconnected (tripped). If relays RL1 and RL2 are not disconnected, the controller 230 determines in step S208 that the current detector 240 cannot perform the sensing operation of the test current ILT or that relays RL1 and RL2 cannot be disconnected, and provides a warning signal. On the other hand, if relays RL1 and RL2 are disconnected to make the electrical value of the test current ILT equal to 0, the controller 230 generates a timing value CV in step S209.

[0076] In step S210, the controller 230 determines whether relays RL1 and RL2 are aging based on the timing value CV. In one embodiment, in response to the timing value CV being greater than a set value SV, the controller 230 determines in step S211 that at least one of the relays RL1 and RL2 is aging and provides a warning signal. On the other hand, in response to the timing value CV being less than or equal to the set value SV, the controller 230 determines in step S212 that relays RL1 and RL2 are not aging and allows the charging station 10 to perform charging operations.

[0077] Based on the above, in detection method S200, steps S202 and S203 detect whether relays RL1 and RL2 are operating normally (e.g., whether they are conducting normally). Steps S205 to S212 detect the aging condition of relays RL1 and RL2.

[0078] In summary, the detection device and method of the present invention generate a timing value based on the duration of the test current being generated. This timing value is related to the time taken for the relay to trip. In this way, the detection device and method can determine the aging condition of the relay based on the timing value.

[0079] Although the present invention has been disclosed above with reference to embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some changes and modifications without departing from the concept and scope of the present invention. Therefore, the scope of protection of the present invention shall be determined by the claims.

Claims

1. A detection device for a charging pile, wherein the charging pile includes a first power line, a second power line, a first output terminal, a second output terminal, and a relay, wherein the second output terminal is connected to the second power line, wherein a first terminal of the relay is connected to the first power line, and wherein a second terminal of the relay is connected to the first output terminal, wherein the detection device includes: A virtual load circuit is connected between the second output terminal and the second terminal of the relay; A detection circuit is connected to the first power line and the second power line; as well as A controller, connected to the relay, the virtual load circuit, and the detection circuit, is configured to: The relay is turned on, and the virtual load circuit is controlled to form a virtual load path between the second output terminal and the second terminal of the relay. The detection circuit is controlled to generate a test current between the first power line and the second power line, and the duration for which the test current is generated is timed. The relay is disconnected based on the test current to stop generating the test current, and the timing of the duration is stopped to generate a timing value. The aging condition of the relay can be determined based on this timing value.

2. The detection device as claimed in claim 1, wherein the controller determines whether the relay is aging based on a comparison between the timing value and a set value.

3. The detection device as claimed in claim 2, wherein the controller determines that the relay is aging in response to the timing value being greater than the set value.

4. The detection device as described in claim 1, further comprising: A first current detector, connected to the controller, is configured to generate a current detection signal in response to the test current.

5. The detection device as described in claim 4, wherein: The controller times the duration for which the test current is generated based on the current detection signal and provides a control signal. The relay is disconnected based on the control signal.

6. The detection device as described in claim 5, further comprising: A second current detector, connected to the controller, is configured to sense the test current flowing through one of the first power line and the second power line to generate a sensing signal, and provides the sensing signal to the controller. In response to the sensing signal indicating that the current value of the test current is equal to 0, the controller stops timing to generate the timing value.

7. The detection device as claimed in claim 1, wherein the detection circuit comprises: A programmable resistor circuit; as well as A test switch is connected in series with the programmable resistor circuit between the first power line and the second power line; During the period when the virtual load path is provided, the controller turns on the test switch and adjusts the resistance value of the programmable resistor circuit to bring the test current value to a set current value.

8. The detection device as described in claim 7, further comprising: A voltage sensor is configured to sense the voltage value located on the first power line to generate a voltage sensing signal. The controller adjusts the resistance value of the programmable resistor circuit based on the voltage sensing signal and the set current value to achieve the set current value for the test current.

9. The detection device as claimed in claim 1, wherein the virtual load circuit comprises: A virtual load; as well as A load switch is connected in series with the virtual load between the second output terminal and the second terminal of the relay. The controller activates the relay and the load switch to form the virtual load path.

10. A detection method for a charging pile, wherein the charging pile includes a first power line, a second power line, a first output terminal, a second output terminal, and a relay, wherein the second output terminal is connected to the second power line, wherein a first terminal of the relay is connected to the first power line, and wherein a second terminal of the relay is connected to the first output terminal, wherein the detection method includes: A virtual load circuit and a detection circuit are provided, wherein the virtual load circuit is connected between the second output terminal and the second terminal of the relay, and the detection circuit is connected to the first power line and the second power line; The relay is turned on, and the virtual load circuit is controlled to form a virtual load path between the second output terminal and the second terminal of the relay. The detection circuit is controlled to generate a test current between the first power line and the second power line, and the duration of time during which the test current is generated is timed. The relay is disconnected based on the test current to stop generating the test current, and the timing of the duration is stopped to generate a timing value; and The aging condition of the relay can be determined based on this timing value.

11. The detection method as described in claim 10, wherein the step of determining the aging condition of the relay based on the timing value includes: The relay is judged to be aged based on the comparison between the timing value and a set value.

12. The detection method as described in claim 11, wherein the step of determining whether the relay is aged based on the comparison result between the timing value and the set value includes: In response to the timing value exceeding the set value, the relay is determined to be aging and a warning signal is provided.

13. The detection method as described in claim 11, wherein the step of determining whether the relay is aged based on the comparison result between the timing value and the set value includes: If the timing value is less than or equal to the set value, it is determined that the relay is not worn out, and the charging station is allowed to perform charging operations.

14. The detection method of claim 10, wherein the steps of controlling the detection circuit to generate the test current between the first power line and the second power line, and timing the duration for which the test current is generated, include: A current detection signal is generated in response to the test current; as well as The duration of the test current being generated is timed based on the current detection signal, and a control signal is provided. The relay is disconnected based on the control signal.

15. The detection method as described in claim 14, further comprising: In response to the relay's inability to be disconnected according to the control signal, a warning signal is provided.

16. The detection method of claim 14, wherein the steps of disconnecting the relay to stop generating the test current based on the test current and ending the timing of the time length to generate the timing value include: The test current flowing through one of the first power line and the second power line is sensed to generate a sensing signal; In response to the sensing signal indicating that the current value of the test current is equal to 0, the timing is stopped to generate the timing value.

17. The detection method of claim 10, wherein the detection circuit includes a programmable resistor circuit and a test switch, wherein the test switch and the programmable resistor circuit are connected in series between the first power line and the second power line, wherein the step of controlling the detection circuit to generate the test current between the first power line and the second power line includes: During the period when the virtual load path is provided, the test switch is turned on, and the resistance value of the programmable resistor circuit is adjusted to bring the test current value to a set current value.

18. The detection method as described in claim 17, further comprising: The voltage value located on the first power line is sensed to generate a voltage sensing signal; as well as The resistance value of the programmable resistor circuit is adjusted according to the voltage sensing signal and the set current value so that the current value of the test current reaches the set current value.

19. The detection method of claim 10, wherein the virtual load circuit includes a virtual load and a load switch, wherein the load switch and the virtual load are connected in series between the second output terminal and the second terminal of the relay, wherein the step of turning on the relay and controlling the virtual load circuit to form the virtual load path between the second output terminal and the second terminal of the relay includes: Turn on the relay and the load switch to form the virtual load path.

20. The detection method as described in claim 19, further comprising: Determine if there is current flowing through the virtual load path; as well as In response to the absence of current flowing through the virtual load path, it is determined that one of the relays and the load switch is malfunctioning and an alarm signal is provided.

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