# US 2023/0406136 A1 · Detection Circuit, Anti-Backflow System, and Charging Pile > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2023/0406136 A1 - Document ID: US20230406136A1 - Status: Published application - Kind: A1 - Application number: 18/460,026 - Filed: 2023-09-01 - Published: 2023-12-21 - Earliest claimed: 2021-03-04 - Assignees: Huawei Digital Power Technologies Co., Ltd. - Applicants: Huawei Digital Power Technologies Co., Ltd. - Inventors: Zhenting Jiang; Jiansheng Chen; Yaping Liu; Jianhui Xiong - Web page: https://patentgrep.com/patent/US20230406136A1 ## CPC - B60L 3/003: {relating to inverters} - B60L 53/62: in response to charging parameters, e.g. current, voltage or electrical charge - B60L 53/22: Constructional details or arrangements of charging converters specially adapted for charging electric vehicles - H02J 1/108: having arrangements for blocking reverse current flow, e.g. using diodes (H02J1/12 takes precedence) - H02J 7/60: including safety or protection arrangements - H02J 7/80: including monitoring or indicating arrangements - B60L 2210/30: AC to DC converters - B60L 2240/529: Current - B60L 2240/549: Current - H02J 2105/37: exchanging power with electric vehicles [EV] or with hybrid electric vehicles [HEV] - H02J 2207/10: Control circuit supply, e.g. means for supplying power to the control circuit - Y02T 10/70: Energy storage systems for electromobility, e.g. batteries - Y02T 10/7072: Electromobility specific charging systems or methods for batteries, ultracapacitors, supercapacitors or double-layer capacitors - Y02T 90/12: Electric charging stations - B60L: PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES (arrangements or mounting of electrical propulsion units or of plural diverse prime-movers for mutual or common propulsion in vehicles B60K1/00, B60K6/20; arrangements or mounting of electrical gearing in vehicles B60K17/12, B60K17/14; preventing wheel slip by reducing power in rail vehicles B61C15/08; dynamo-electric machines H02K; control or regulation of electric motors H02P); SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES (electric coupling devices combined with mechanical couplings of vehicles B60D1/64; electric heating for vehicles B60H1/00); ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL (control or regulation of electric motors H02P); MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES - H02J: ELECTRIC POWER NETWORKS; CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY - Y02T: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION ## Abstract A detection circuit includes a detection power supply and a digital unit that are connected in series. A first end and a second end of the detection circuit are respectively connected to an input end and an output end of an anti-backflow circuit. The detection power supply may make an electric potential at the second end of the detection circuit higher than that at the first end of the detection circuit. When transmitting a detection current, the digital unit may output a first level signal indicating that the anti-backflow circuit fails. The detection current is a current transmitted when a loop is formed between the first end and the second end of the detection circuit. ## Claims ### Claim 1 An apparatus, comprising: a first end configured to be connected to a high-electric-potential input end of an anti-backflow circuit; a second end configured to be connected to a high-electric-potential output end of the anti-backflow circuit; a detection power supply connected to the first end; a digital component connected to the second end; and a detection power supply connected to the first end and the digital component, wherein the detection power supply and the digital component are connected in series between the first end and the second end, and wherein the detection power supply is configured to: apply bias voltages to the first end and the second end to make a first electric potential at the second end higher than a second electric potential at the first end; transmit a detection current between the first end and the second end when a current loop is formed between the first end and the second end; and output a first level signal when transmitting the detection current, wherein the first level signal indicates that the anti-backflow circuit has failed. ### Claim 2 (depends on 1) The apparatus of claim 1, wherein the digital component is further configured to output a second level signal when the digital component does not transmit the detection current, and wherein the second level signal indicates that the anti-backflow circuit has not failed. ### Claim 3 (depends on 1) The apparatus of claim 1, wherein the detection power supply comprises: a positive electrode; and a negative electrode connected to the first end, and wherein the digital component comprises: a current input end connected to the positive electrode; a current output end connected to the second end; and a signal output end configured to output the first level signal. ### Claim 4 (depends on 1) The apparatus of claim 1, further comprising a breaking circuit connected in series to both the detection power supply and the digital component, wherein the breaking circuit is configured to: electrically connect the detection power supply and the digital component during failure detection of the anti-backflow circuit; and electrically disconnect the detection power supply and the digital component when the failure detection ends. ### Claim 5 (depends on 1) The apparatus of claim 1, further comprising a detection diode connected in series to both the detection power supply and the digital component, wherein the detection diode comprises: an anode configured to receive the detection current; and a cathode configured to output the detection current. ### Claim 6 (depends on 1) The apparatus of claim 1, further comprising a detection resistor connected in series to both the detection power supply and the digital component. ### Claim 7 (depends on 1) The apparatus of claim 1, wherein the digital component comprises: a primary-side circuit configured to transmit the detection current; and a secondary-side circuit configured to output the first level signal when the primary circuit transmits the detection current, and wherein the secondary-side circuit and the primary-side circuit are isolated from each other. ### Claim 8 (depends on 7) The apparatus of claim 7, wherein the primary-side circuit comprises a light-emitting diode comprising: an anode configured to receive the detection current; and a cathode configured to output the detection current, wherein the light-emitting diode is configured to emit light when transmitting the detection current, wherein the secondary-side circuit comprises a light-sensing switching transistor configured to be turned on when the light-emitting diode emits light, and wherein the secondary-side circuit outputs the first level signal when the light-sensing switching transistor is turned on. ### Claim 9 (depends on 1) The apparatus of claim 1, further comprising a signal acquisition circuit configured to perform shaping filtering on the first level signal. ### Claim 10 A system, comprising: an anti-backflow circuit comprising: a high-electric-potential input end; and a high-electric-potential output end; and a detection circuit configured to perform failure detection on the anti-backflow circuit and comprising: a first end configured to be connected to the high-electric-potential input end; a second end configured to be connected to the high-electric-potential output end; a detection power supply connected to the first end; a digital component connected to the second end; and a detection power supply connected to the first end and the digital component, wherein the detection power supply and the digital component are connected in series between the first end and the second end, and wherein the detection power supply is configured to: apply bias voltages to the first end and the second end to make a first electric potential at the second end higher than a second electric potential at the first end; transmit a detection current between the first end and the second end when a current loop is formed between the first end and the second end; and output a first level signal when transmitting the detection current, wherein the first level signal indicates that the anti-backflow circuit has failed. ### Claim 11 (depends on 10) The system of claim 10, wherein the digital component is further configured to output a second level signal when the digital component does not transmit the detection current, and wherein the second level signal indicates that the anti-backflow circuit has not failed. ### Claim 12 (depends on 10) The system of claim 10, wherein the detection power supply comprises: a positive electrode; and a negative electrode connected to the first end, and wherein the digital component comprises: a current input end connected to the positive electrode; a current output end connected to the second end; and a signal output end configured to output the first level signal. ### Claim 13 (depends on 10) The system of claim 10, wherein the detection circuit further comprises a breaking circuit connected in series to both the detection power supply and the digital component, and wherein the breaking circuit is configured to: electrically connect the detection power supply and the digital component during failure detection of the anti-backflow circuit; and electrically disconnect the detection power supply and the digital component when the failure detection ends. ### Claim 14 (depends on 10) The system of claim 10, wherein the detection circuit further comprises a detection diode connected in series to both the detection power supply and the digital component, and wherein the detection diode comprises: an anode configured to receive the detection current; and a cathode configured to output the detection current. ### Claim 15 (depends on 10) The system of claim 10, wherein the detection circuit further comprises a detection resistor connected in series to both the detection power supply and the digital component. ### Claim 16 (depends on 10) The system of claim 10, wherein the digital component comprises: a primary-side circuit configured to transmit the detection current; and a secondary-side circuit configured to output the first level signal when the primary circuit transmits the detection current, and wherein the secondary-side circuit and the primary-side circuit are isolated from each other. ### Claim 17 (depends on 16) The system of claim 16, wherein the primary-side circuit comprises a light-emitting diode comprising: an anode configured to receive the detection current; and a cathode configured to output the detection current, wherein the light-emitting diode is configured to emit light when transmitting the detection current, wherein the secondary-side circuit comprises a light-sensing switching transistor configured to be turned on when the light-emitting diode emits light, and wherein the secondary-side circuit outputs the first level signal when the light-sensing switching transistor is turned on. ### Claim 18 (depends on 10) The system of claim 10, wherein the detection circuit further comprises a signal acquisition circuit configured to perform shaping filtering on the first level signal. ### Claim 19 An apparatus, comprising: a conversion circuit configured to: receive alternating current electric power; convert the alternating current electric power into direct current electric power; and output the direct current electric power; and an anti-backflow system configured to: receive the direct current electric power from the conversion circuit; and output the direct current electric power to a battery, wherein the anti-backflow system comprises: an anti-backflow circuit comprising: a high-electric-potential input end; and a high-electric-potential output end; and a detection circuit configured to perform failure detection on the anti-backflow circuit and comprising: a first end configured to be connected to the high-electric-potential input end; a second end configured to be connected to the high-electric-potential output end; a detection power supply connected to the first end; a digital component connected to the second end, a detection power supply connected to the first end and the digital component, wherein the detection power supply and the digital component are connected in series between the first end and the second end, and wherein the detection power supply is configured to: apply bias voltages to the first end and the second end to make a first electric potential at the second end higher than a second electric potential at the first end; transmit a detection current between the first end and the second end when a current loop is formed between the first end and the second end; and output a first level signal when transmitting the detection current, wherein the first level signal indicates that the anti-backflow circuit has failed. ### Claim 20 (depends on 19) The apparatus of claim 19, further comprising a control circuit connected to both the conversion circuit and the digital component and configured to receive the first level signal, wherein after receiving the first level signal, the control circuit is configured to prohibit the conversion circuit from outputting the direct current electric power.