High-safety dual-power switching device, power supply system and vehicle

Abstract

The utility model provides a double power supply switching device with high safety, a power supply system and a vehicle, comprising a double-pole double-throw relay, a first bus and a second bus, a first end of a normally closed contact of the double-pole double-throw relay is connected with a first end of the first bus, a second end of the first bus is used for being connected with a second power supply, and a second end of the second bus is used for being connected with a third power supply. The second end of the normally closed contact of the double-pole double-throw relay is connected with the first end of a second bus, and the second end of the second bus is used for being connected with a second power supply; the dual-power-supply switching device further comprises a first relay, a second relay, a third relay and a fourth relay. The relays are single-pole normally-open relays. The first relay and the second relay are connected in series on the first bus, and the third relay and the fourth relay are connected in series on the second bus. The at least two relays are arranged on the bus, and then the electric gap between the two power supplies is opened, so that the electric gap is increased, and the insulation and voltage resistance are improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to new energy field especially, it relates to a high security dual power supply switching device, power supply system and traffic tool. BACKGROUND

[0002] New energy traffic tool has many characteristics such as environmental protection, little pollution because it does not burn gasoline or diesel to generate power, and under the vigorous popularization and application of new energy generation such as water energy, wind energy, solar energy and nuclear energy, many new energy traffic tools are gradually popularized and applied, such as new energy electric car, new energy electric bus, new energy electric truck, new energy electric cleaning vehicle, new energy electric rail traffic tool, new energy electric flight traffic tool, new energy electric navigation traffic tool, etc.

[0003] In order to reduce the cost, reduce the size of parts and reduce the connecting cable of optimizing the internal parts of the car, the original independent OBC part and DCDC part are now integrated into an integrated power supply system, which achieves the above-mentioned target, and the existing power supply integration scheme is to use a dual power supply switching device composed of a general relay to realize OBC and DCDC function, which integrates OBC and DCDC to the greatest extent, reduces the number of high-voltage power switches and improves the reliability of the system, and because the PFC Boost circuit is shared, the input working voltage range of DCDC can be greatly expanded, which meets the application requirements of wide input range DCDC.

[0004] In the above-mentioned integrated power supply system integration scheme, the system is powered by alternating current in charging mode, and is powered by power battery in driving mode, and the electrical insulation isolation between alternating current and power battery must meet the following safety regulations, first, the electrical gap must meet the safety requirements, second, the insulation withstand voltage also needs to meet the safety requirements, and third, in the event of a single point failure, it cannot endanger human safety, therefore, the application of relay meets the above-mentioned safety requirements is particularly key. UTILITY MODEL CONTENTS

[0005] The first object of the utility model is to provide a high security dual power supply switching device.

[0006] The second object of the utility model is to provide a power supply system with the above-mentioned dual power supply switching device.

[0007] The third object of the utility model is to provide a traffic tool with the above-mentioned dual power supply switching device.

[0008] In order to realize the first purpose of the utility model, the utility model provides a kind of high safety's dual power supply switching device, including double-pole double-throw relay, first busbar and second busbar, the common contact of double-pole double-throw relay is used to connect with power module, the normally open contact of double-pole double-throw relay is used to connect with first power supply, the first end of the normally closed contact of double-pole double-throw relay is connected with the first end of first busbar, the second end of first busbar is used to connect with second power supply, the second end of the normally closed contact of double-pole double-throw relay is connected with the first end of second busbar, the second end of second busbar is used to connect with second power supply;Dual power supply switching device further includes first relay, second relay, third relay and fourth relay, first relay, second relay, third relay and fourth relay adopt single-pole normally open relay;First relay and second relay are arranged in series on first busbar, third relay and fourth relay are arranged in series on second busbar.

[0009] From the above scheme, the switching of the first power supply and the second power supply can be realized by the arrangement of the double-pole double-throw relay, and the first busbar and the second busbar are used to connect the branch connected with the second power supply. In the present case, the first relay and the second relay are arranged in series on the first busbar, and the third relay and the fourth relay are arranged in series on the second busbar. By arranging at least two relays on the busbar, the electrical gap between the two power supplies is widened, thereby increasing the electrical gap and improving the insulation withstand voltage.

[0010] Further, the fixed contact of the first relay is connected with the second end of the first busbar, the movable contact of the first relay is connected with the fixed contact of the second relay, and the movable contact of the second relay is connected with the first end of the first busbar.

[0011] Further, the fixed contact of the third relay is connected with the second end of the second busbar, the movable contact of the third relay is connected with the fixed contact of the fourth relay, and the movable contact of the fourth relay is connected with the first end of the second busbar.

[0012] Further, the dual power supply switching device further includes a first open-circuit fault detection circuit, a first open-circuit detection point is arranged between the first relay and the second relay, a second open-circuit detection point is arranged between the third relay and the fourth relay, and the first open-circuit fault detection circuit is used to detect the open-circuit fault of the first open-circuit detection point and / or the second open-circuit detection point.

[0013] Further, the first open-circuit fault detection circuit includes a first optocoupler, a first resistor and a second resistor, the first end of the first resistor is connected with the first open-circuit detection point, the second end of the first resistor is connected with the positive electrode of the first optocoupler, the negative electrode of the first optocoupler is connected with the second open-circuit detection point, the emitter of the first optocoupler is connected with the power supply end, the collector of the first optocoupler is connected with the first end of the second resistor, and the second end of the second resistor is grounded.

[0014] Further, the dual power supply switching device further comprises a second open-circuit fault detection circuit, a third open-circuit detection point is arranged between the second relay and the first end of the first bus, a fourth open-circuit detection point is arranged between the fourth relay and the first end of the second bus, and the second open-circuit fault detection circuit is configured to detect an open-circuit fault of the third open-circuit detection point and / or the fourth open-circuit detection point.

[0015] Further, the second open-circuit fault detection circuit comprises a second optocoupler, a third resistor and a fourth resistor, a first end of the third resistor is connected with the third open-circuit detection point, a second end of the third resistor is connected with a positive electrode of the second optocoupler, a negative electrode of the second optocoupler is connected with the fourth open-circuit detection point, an emitter of the second optocoupler is connected with the power supply end, a collector of the second optocoupler is connected with a first end of the fourth resistor, and a second end of the fourth resistor is grounded.

[0016] As can be seen from the above, the open-circuit fault detection circuit can detect the open-circuit fault of each relay, and the optocoupler isolation detection circuit can sequentially detect the two relays on the two buses, thereby further improving the safety of the circuit.

[0017] In order to achieve the second purpose of the utility model, the utility model provides a power supply system, which comprises a first power supply, a second power supply, a power consumption module and the dual power supply switching device.

[0018] In order to achieve the third purpose of the utility model, the utility model provides a traffic tool, which comprises the power supply system. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 is the circuit diagram of the power supply system embodiment of the utility model.

[0020] Figure 2 is the flow chart of the starting step of the power supply system embodiment of the utility model.

[0021] Figure 3 is the flow chart of the relay fault judgment step of the power supply system embodiment of the utility model.

[0022] The utility model will be further described below in combination with the drawings and embodiments. DETAILED DESCRIPTION

[0023] Referring to Figure 1The power supply system comprises a first power supply, a second power supply, a power consumption module and a dual power supply switching device. The dual power supply switching device comprises a double-pole double-throw relay K1, a first bus L1, a second bus L2, a first relay K11, a second relay K21, a third relay K12, a fourth relay K22, a first open-circuit fault detection circuit F11 and a second open-circuit fault detection circuit F12. The common contact (port 1, 4) of the double-pole double-throw relay K1 is used to be connected with the power consumption module F1. The normally open contact (port 3, 6) of the double-pole double-throw relay K1 is used to be connected with the first power supply. The first end of the normally closed contact (port 5) of the double-pole double-throw relay K1 is connected with the first end P1 of the first bus L1. The second end P2 of the first bus L1 is used to be connected with the second power supply. The second end (port 5) of the normally closed contact of the double-pole double-throw relay K1 is connected with the first end P3 of the second bus L2. The second end P4 of the second bus L2 is used to be connected with the second power supply. In the embodiment, the first power supply can adopt an alternating current rectifier power supply F2, that is, the system is powered by alternating current in the charging mode. The second power supply can adopt a power battery F3.

[0024] The first relay K11, the second relay K21, the third relay K12 and the fourth relay K22 adopt single-pole normally open relays. The first relay K11 and the second relay K21 are arranged in series on the first bus L1. The third relay K12 and the fourth relay K22 are arranged in series on the second bus L2. Specifically, the fixed contact of the first relay K11 is connected with the second end of the first bus L1. The movable contact of the first relay K11 is connected with the fixed contact of the second relay K21. The movable contact of the second relay K21 is connected with the first end of the first bus L1. The fixed contact of the third relay K12 is connected with the second end of the second bus L2. The movable contact of the third relay K12 is connected with the fixed contact of the fourth relay K22. The movable contact of the fourth relay K22 is connected with the first end of the second bus L2.

[0025] The first open-circuit detection point P51 is arranged between the first relay K11 and the second relay K21. The second open-circuit detection point P52 is arranged between the third relay K12 and the fourth relay K22. The third open-circuit detection point P53 is arranged between the second relay K21 and the first end of the first bus L1. The fourth open-circuit detection point P54 is arranged between the fourth relay K22 and the first end of the second bus L2.

[0026] The first open-circuit fault detection circuit F11 comprises a first optocoupler U1, a first resistor R1 and a second resistor R2. The first end of the first resistor R1 is connected with the first open-circuit detection point P51, the second end of the first resistor R1 is connected with the anode of the first optocoupler U1, the cathode of the first optocoupler U1 is connected with the second open-circuit detection point P52, the emitter of the first optocoupler U1 is connected with the power supply terminal VCC, the collector of the first optocoupler U1 is connected with the first end of the second resistor R2, the second end of the second resistor R2 is grounded, and the collector of the first optocoupler U1 is further connected with the first signal feedback terminal JDsig1.

[0027] The second open-circuit fault detection circuit F12 comprises a second optocoupler U2, a third resistor R3 and a fourth resistor R4. The first end of the third resistor R3 is connected with the third open-circuit detection point P53, the second end of the third resistor R3 is connected with the anode of the second optocoupler U2, the cathode of the second optocoupler U2 is connected with the fourth open-circuit detection point P54, the emitter of the second optocoupler U2 is connected with the power supply terminal VCC, the collector of the second optocoupler U2 is connected with the first end of the fourth resistor R4, the second end of the fourth resistor R4 is grounded, and the collector of the second optocoupler U2 is further connected with the second signal feedback terminal JDsig2.

[0028] By switching the double-pole double-throw relay K1, the switching use of the first power supply or the second power supply can be realized, and before switching the use of the second power supply, the relay fault can be judged. Referring to Figure 2 , first, the starting step is executed. When the system receives the wake-up signal, the auxiliary power supply starts to work, and keeps K1, K11, K12, K21 and K22 in the open state. Then, the relay fault judgment step is executed.

[0029] Referring to Figure 3 , when the relay fault judgment step is executed, K11 is first closed. Then, it is judged whether JDsig1=0 is established. If not, K12 has a sticking fault. Then, the fault is reported again and the work is stopped.

[0030] If JDsig1=0 is established, K12 is closed. Then, it is judged again whether JDsig1=0 is established. If yes, K11 or K12 or both has an open-circuit fault. Then, the fault is reported and the work is stopped.

[0031] If JDsig1=0 is not established, K11 is opened. Then, it is judged whether JDsig1=1 is established. If yes, K11 has a sticking fault. Then, the fault is reported and the work is stopped.

[0032] If JDsig1=1 is not established, the fault judgment of the first relay K11 and the third relay K12 is completed. If both are normal, K11 and K12 are closed to enter the next level of relay fault judgment.

[0033] Then close k21, and then determine whether JDsig2=0 is true, if not, then K22 exists adhesion failure, and then report the failure and stop working.

[0034] If JDsig2=0 is true, then close K22, and then determine whether JDsig2=0 is true again, if true, then K21 or K22 or both exist open circuit failure, and then report the failure and stop working.

[0035] If JDsig2=0 is not true, then open K21, and then determine whether JDsig2=1 is true, if true, then K21 exists adhesion failure, and then report the failure and stop working.

[0036] If JDsig2=1 is not true, then complete the failure judgment of the second relay K21 and the fourth relay K22, and the results are normal, end the relay failure judgment program, and then enter the next step of work.

[0037] The vehicle includes the power supply system as described above, and the vehicle can be a new energy electric car, a new energy electric bus, a new energy electric truck, a new energy electric cleaning vehicle, a new energy electric rail vehicle, a new energy electric flight vehicle, a new energy electric shipping vehicle, etc.

[0038] Of course, in the present embodiment, the first open circuit failure detection circuit F11 is used to detect the open circuit failure of the first open circuit detection point P51 and the second open circuit detection point P52, and the second open circuit failure detection circuit F12 is used to detect the open circuit failure of the third open circuit detection point P53 and the fourth open circuit detection point P54. In addition to the present embodiment, there are other implementation modes, such as a voltage or current detection type detection circuit, which can also realize the open circuit detection of the relay, and each individual relay can also be configured with an open circuit failure detection circuit, that is, each relay can be detected individually. In addition, in addition to setting two relays on each bus, two or more relays can be set in series, and the open circuit failure detection circuit configured for the relays can also achieve the purpose of the present case. Furthermore, the arrangement of the first power supply and the second power supply can be selected according to actual application requirements, such as switching between two alternating current power supplies, switching between an alternating current power supply and a direct current power supply, or switching between two direct current power supplies, which can all be adapted to the dual power supply switching device, and all of them can achieve the purpose of the present case.

[0039] From the above, through the arrangement of the double-pole double-throw relay, the switching of the first power supply and the second power supply can be realized, and the first bus and the second bus are connected on the branch connected with the second power supply, the first relay and the second relay are arranged in series on the first bus, and the third relay and the fourth relay are arranged in series on the second bus, at least two relays are arranged on the bus, the electrical gap between the two power supplies is pulled apart, so that the increased electrical gap and the improved insulation withstand voltage are realized.

Claims

1. A high-safety dual power switching device, comprising a double-pole double-throw relay, a first bus and a second bus, a common contact of the double-pole double-throw relay being used to connect with a power module, a normally open contact of the double-pole double-throw relay being used to connect with a first power supply, a first end of a normally closed contact of the double-pole double-throw relay being connected with a first end of the first bus, a second end of the first bus being used to connect with a second power supply, a second end of the second bus being used to connect with the second power supply. Characterized in that: the dual power switching device further comprises a first relay, a second relay, a third relay and a fourth relay, the first relay, the second relay, the third relay and the fourth relay being single-pole normally open relays; the first relay and the second relay are arranged in series on the first bus, and the third relay and the fourth relay are arranged in series on the second bus.

2. The dual power switching device according to claim 1, characterized in that: a fixed contact of the first relay is connected with the second end of the first bus, a movable contact of the first relay is connected with a fixed contact of the second relay, and a movable contact of the second relay is connected with the first end of the first bus.

3. The dual power switching device according to claim 1, characterized in that: a fixed contact of the third relay is connected with the second end of the second bus, a movable contact of the third relay is connected with a fixed contact of the fourth relay, and a movable contact of the fourth relay is connected with the first end of the second bus.

4. The dual power switching device according to any one of claims 1 to 3, characterized in that: the dual power switching device further comprises a first open-circuit fault detection circuit, a first open-circuit detection point is arranged between the first relay and the second relay, a second open-circuit detection point is arranged between the third relay and the fourth relay, and the first open-circuit fault detection circuit is used to detect an open-circuit fault of the first open-circuit detection point and / or the second open-circuit detection point.

5. The dual power switching device according to claim 4, characterized in that: the first open-circuit fault detection circuit comprises a first optocoupler, a first resistor and a second resistor, a first end of the first resistor is connected with the first open-circuit detection point, a second end of the first resistor is connected with a positive electrode of the first optocoupler, a negative electrode of the first optocoupler is connected with the second open-circuit detection point, an emitter of the first optocoupler is connected with a power supply end, a collector of the first optocoupler is connected with a first end of the second resistor, and a second end of the second resistor is grounded.

6. The dual power switching device according to any one of claims 1 to 3, characterized in that: The dual power switching device further comprises a second open-circuit fault detection circuit, a third open-circuit detection point is arranged between the second relay and the first end of the first bus, a fourth open-circuit detection point is arranged between the fourth relay and the first end of the second bus, and the second open-circuit fault detection circuit is configured to detect an open-circuit fault of the third open-circuit detection point and / or the fourth open-circuit detection point.

7. The dual power switching device according to claim 6, characterized in that: The second open-circuit fault detection circuit comprises a second optocoupler, a third resistor and a fourth resistor, a first end of the third resistor is connected with the third open-circuit detection point, a second end of the third resistor is connected with a positive electrode of the second optocoupler, a negative electrode of the second optocoupler is connected with the fourth open-circuit detection point, an emitter of the second optocoupler is connected with a power supply end, a collector of the second optocoupler is connected with a first end of the fourth resistor, and a second end of the fourth resistor is grounded.

8. A power supply system characterized by comprising: A power supply system comprising a first power supply, a second power supply, a power consumption module and the dual power switching device according to any one of claims 1 to 7.

9. Vehicle, characterized in that The power supply system according to claim 8.

Images