Hybrid energy storage inverter auxiliary source input control circuit

Abstract

The utility model provides a kind of hybrid energy storage inverter auxiliary source input control circuit, comprising: voltage detection module, voltage detection module includes first voltage detection unit and second voltage detection unit, the input end of first voltage detection unit is connected to battery side power point;The input end of second voltage detection unit is connected to DC bus side power point;Switching execution module, including first switching unit and second switching unit, the input end of first switching unit is connected to the output end of first voltage detection unit;The input end of second switching unit is connected to the output end of second voltage detection unit, when first voltage detection unit detects that battery side voltage reaches voltage stabilizing threshold, first switching unit cuts off power grid side input passage;When second voltage detection unit detects that DC bus side voltage reaches voltage stabilizing threshold, second switching unit simultaneously cuts off power grid side input passage and battery side input passage.It is realized by hardware control completely, without software intervention.

Description

Technical Field

[0001] This utility model relates to the field of auxiliary power supply technology for hybrid energy storage inverters, and specifically to an auxiliary power input control circuit for hybrid energy storage inverters. Background Technology

[0002] Hybrid energy storage inverter systems operate under complex conditions, placing high demands on the reliability of auxiliary power supply. To save costs, the auxiliary power supply draws power from multiple points simultaneously, such as... Figure 1 It includes three power intake points: the grid side, the battery side, and the DC bus side. Each power intake point is protected from reverse current by diodes. As long as one of the power sources is in normal operation, the auxiliary power source can operate normally. That is, the auxiliary power source's power supply ports DC+ and DC- have the voltage required for the auxiliary power source to operate normally.

[0003] However, the drawback of this scheme is that when the system is working normally, if these power points exist at the same time, due to the influence of parasitic parameters such as the leakage current of the diode, some abnormal voltages will inevitably be coupled out at the ports that are not powered, which will cause the system to misjudge the power supply status.

[0004] To address the aforementioned problems, existing technologies typically connect normally closed relays in series in each power supply circuit, such as... Figure 2 As shown, when any one of P1, P2, or P3 has a normal power supply, both the DC+ and DC- terminals can generate the input voltage for the auxiliary power source. When the voltage across the battery or the bus is detected to meet the requirements for normal auxiliary power source operation, the relay on the auxiliary power source's grid input side is disconnected, thus cutting off the grid input from the auxiliary power source's power supply input. Similarly, when the voltage across the bus is detected to meet the requirements for normal auxiliary power source operation, the relays on both the auxiliary power source's grid input side and the auxiliary power source's battery input side are disconnected, thus cutting off the grid and battery input from the auxiliary power source's power supply input. However, relay control is usually achieved through an MCU, which necessitates real-time monitoring of AC port voltage, battery voltage, and DC bus voltage, increasing software workload and consuming I / O and ADC resources.

[0005] Therefore, in order to reduce the workload of software and save IO and ADC resources, it is necessary to design a hybrid energy storage inverter auxiliary power input control circuit that is completely controlled by hardware. Utility Model Content

[0006] To address the aforementioned technical problems, this utility model provides an auxiliary power input control circuit for a hybrid energy storage inverter. The auxiliary power input includes at least a battery-side power drawpoint and a DC bus-side power drawpoint. The circuit includes: A voltage detection module is configured to detect whether the battery-side voltage or the DC bus-side voltage has reached a voltage regulation threshold. The voltage detection module includes a first voltage detection unit and a second voltage detection unit. The input terminal of the first voltage detection unit is connected to the battery-side power extraction point; the input terminal of the second voltage detection unit is connected to the DC bus-side power extraction point. The switching execution module includes a first switching unit and a second switching unit. The input terminal of the first switching unit is connected to the output terminal of the first voltage detection unit; the input terminal of the second switching unit is connected to the output terminal of the second voltage detection unit, wherein: When the first voltage detection unit detects that the battery-side voltage reaches the voltage regulation threshold, the first switching unit cuts off the grid-side input path; When the second voltage detection unit detects that the DC bus side voltage reaches the voltage regulation threshold, the first switching unit and the second switching unit simultaneously cut off the grid side input path and the battery side input path.

[0007] Furthermore, the first voltage detection unit and the second voltage detection unit include a voltage regulator chip: The input terminal of the voltage regulator chip is connected to the corresponding input port through a voltage divider resistor; The output terminals of the voltage regulator chip are respectively connected to the first switching unit and the second switching unit.

[0008] Furthermore, an electrical isolation unit is provided between the voltage detection module and the switching execution module, and the first voltage detection unit and the second voltage detection unit are respectively connected to the corresponding first switching unit and second switching unit through the electrical isolation unit.

[0009] Furthermore, the electrical isolation unit includes an optocoupler.

[0010] Furthermore, the first switching unit and the second switching unit include relays: The anode of the light-emitting diode in the optocoupler is connected to the auxiliary power source through a current-limiting resistor; The cathode of the light-emitting diode of the optocoupler is connected to the output terminals of the first voltage detection unit and the second voltage detection unit. The collector of the phototransistor in the optocoupler is connected to one end of the corresponding relay. The emitter of the phototransistor in the optocoupler is grounded.

[0011] Preferably, all of the relays are normally closed relays.

[0012] Preferably, the voltage regulator chip is model TL431.

[0013] Compared with the prior art, the present invention has the following beneficial effects: This invention is entirely controlled by hardware, enabling switching management between multiple auxiliary power inputs of the hybrid energy storage inverter without software intervention, thus avoiding the occupation of ADC and IO resources. Attached Figure Description

[0014] Figure 1 A partial circuit diagram of the auxiliary power supply port of a hybrid energy storage inverter in the prior art; Figure 2 In the existing technology Figure 1 Partial circuit diagram of normally closed relays connected in series at each power input port; Figure 3 This is a schematic diagram of the auxiliary power input control circuit of the hybrid energy storage inverter disclosed in an embodiment of the present invention.

[0015] In the picture: 001. Battery-side power draw point; 002. DC bus-side power draw point; 100, Voltage detection module; 110, First voltage detection unit; 120, Second voltage detection unit; U2, U4, Voltage regulator chips; 200, Switching execution module; 210, First switching unit; 220, Second switching unit; K1, K2, Relays; 300, Electrical isolation unit; U1, U3, Optocouplers. Detailed Implementation

[0016] To make the technical solutions and effects of this utility model clearer, the technical solutions of this utility model will be clearly and completely described below with reference to the accompanying drawings in the embodiments. Obviously, the described embodiments are some embodiments of this utility model, but not all embodiments.

[0017] The present invention aims to provide a hybrid energy storage inverter auxiliary power input control circuit, which is completely controlled by hardware to manage the switching between multiple auxiliary power inputs of the hybrid energy storage inverter without software intervention.

[0018] In this utility model, the auxiliary power source inputs include a battery-side power take-off point 001, a DC bus-side power take-off point 002, and a grid-side power take-off point (the grid-side power take-off point is located at...). Figure 3 Not shown in the image, via Figure 3 (Controlled by relay K1). Figure 3 P4 and P5 are the battery-side power take-off point 001 and the DC bus-side power take-off point 002, respectively.

[0019] Please see Figure 3In this scheme, the auxiliary power input control circuit of the hybrid energy storage inverter mainly includes a voltage detection module 100 and a switching execution module 200; an electrical isolation unit 300 is provided between the voltage detection module 100 and the switching execution module 200, which will be described in detail below.

[0020] The voltage detection module 100 is configured to detect whether the battery-side voltage or the DC bus-side voltage has reached the voltage regulation threshold. The voltage detection module 100 includes a first voltage detection unit 110 and a second voltage detection unit 120. The input terminal of the first voltage detection unit 110 is connected to the battery-side power extraction point 001 and is used to determine whether the battery-side voltage has reached the voltage regulation threshold. The input terminal of the second voltage detection unit 120 is connected to the DC bus-side power extraction point 002 and is used to determine whether the DC bus-side voltage has reached the voltage regulation threshold.

[0021] The switching execution module 200 includes a first switching unit 210 and a second switching unit 220. The input terminal of the first switching unit 210 is connected to the output terminal of the first voltage detection unit 110; the input terminal of the second switching unit 220 is connected to the output terminal of the second voltage detection unit 120. Specifically: when the first voltage detection unit 110 detects that the battery-side voltage reaches the voltage regulation threshold, the first switching unit 210 cuts off the grid-side input path; when the second voltage detection unit 120 detects that the DC bus-side voltage reaches the voltage regulation threshold, the first switching unit 210 and the second switching unit 220 simultaneously cut off both the grid-side input path and the battery-side input path.

[0022] In a further embodiment, an electrical isolation unit 300 is provided between the voltage detection module 100 and the switching execution module 200. The first voltage detection unit 110 and the second voltage detection unit 120 are respectively connected to the corresponding first switching unit 210 and second switching unit 220 through the electrical isolation unit 300.

[0023] The first voltage detection unit 110 and the second voltage detection unit 120 include voltage regulator chips U2 and U4.

[0024] The first switching unit 210 and the second switching unit 220 include relays K1 and K2.

[0025] in: The voltage regulator chip U2 is used to detect the battery side voltage. When the voltage at pin 1 exceeds the set threshold (indicating that the battery voltage meets the auxiliary power supply requirements), pin 2 outputs a low level.

[0026] The voltage regulator chip U4 is used to detect the DC bus voltage. When the voltage at pin 1 exceeds the set threshold, pin 2 outputs a low level.

[0027] The electrical isolation unit 300 includes optocouplers U1 and U3.

[0028] in: Optocoupler U1 receives the output signal of voltage regulator chip U2. When voltage regulator chip U2 outputs a low level, optocoupler U1 is turned on, driving relay K1 to open its normally closed contact, thereby cutting off the grid input.

[0029] Optocoupler U3 receives the output signal from voltage regulator chip U4. When voltage regulator chip U4 outputs a low level, optocoupler U3 is turned on, which simultaneously drives relays K1 and K2 to turn off, thereby cutting off the input from the power grid side and the battery side.

[0030] Specifically: The input terminals of voltage regulator chips U2 and U4 are connected to their corresponding input ports P4 and P5 via voltage divider resistors; the output terminals of voltage regulator chips U2 and U4 are connected to the corresponding first switching unit 210 and second switching unit 220, respectively. The voltage divider resistors are used not only for voltage sampling but also as dead loads or part of the dead loads of the corresponding input ports, used to release induced charges at the ports and improve the system's anti-interference capability.

[0031] The anodes of the light-emitting diodes of optocouplers U1 and U3 are connected to an auxiliary power source through a current-limiting resistor; the cathodes of the light-emitting diodes of optocouplers U1 and U3 are connected to the output terminals of the corresponding first voltage detection unit 110 and second voltage detection unit 120.

[0032] The collectors of the phototransistors in optocouplers U1 and U3 are connected to one end of the coils of the corresponding relays K1 and K2, and the other end of the coils of relays K1 and K2 are connected to the relay drive power supply; the emitters of the phototransistors in optocouplers U1 and U3 are grounded.

[0033] Preferably, the voltage regulator chips U2 and U4 are model TL431.

[0034] Preferably, relays K1 and K2 are both normally closed relays.

[0035] The technical principle of this solution is: When the voltage at the battery-side input port P4 reaches the voltage regulation threshold, the first voltage detection unit 110 outputs a valid signal, which drives the relay K1 to operate through the optocoupler U1, disconnecting its normally closed contacts and thus cutting off the grid-side input path.

[0036] When the voltage at the DC bus input port P5 reaches the voltage regulation threshold, the second switching unit 220 outputs a valid signal, which drives the relays K1 and K2 to operate simultaneously through the optocoupler U2, disconnecting their normally closed contacts, thereby simultaneously cutting off the grid-side input path and the battery-side input path.

[0037] This solution is entirely controlled by hardware, requiring no software intervention, which reduces the software workload and saves resources such as MCU I / O and ADC.

[0038] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A hybrid energy storage inverter auxiliary source input control circuit, the input of the auxiliary source at least comprising a battery side power taking point (001) and a DC bus side power taking point (002), characterized in that, The circuit includes: A voltage detection module (100) is configured to detect whether the battery-side voltage or the DC bus-side voltage has reached a voltage regulation threshold. The voltage detection module (100) includes a first voltage detection unit (110) and a second voltage detection unit (120). The input terminal of the first voltage detection unit (110) is connected to the battery-side power take-off point (001); the input terminal of the second voltage detection unit (120) is connected to the DC bus-side power take-off point (002). The switching execution module (200) includes a first switching unit (210) and a second switching unit (220). The input terminal of the first switching unit (210) is connected to the output terminal of the first voltage detection unit (110); the input terminal of the second switching unit (220) is connected to the output terminal of the second voltage detection unit (120), wherein: When the first voltage detection unit (110) detects that the battery-side voltage reaches the voltage regulation threshold, the first switching unit (210) cuts off the grid-side input path; When the second voltage detection unit (120) detects that the DC bus side voltage reaches the voltage stabilization threshold, the first switching unit (210) and the second switching unit (220) simultaneously cut off the grid side input path and the battery side input path.

2. The hybrid energy storage inverter auxiliary input control circuit of claim 1, wherein, The first voltage detection unit (110) and the second voltage detection unit (120) include voltage regulator chips (U2, U4): The input terminals of the voltage regulator chips (U2, U4) are connected to the corresponding input ports through voltage divider resistors; The output terminals of the voltage regulator chips (U2, U4) are respectively connected to the first switching unit (210) and the second switching unit (220).

3. The hybrid energy storage inverter auxiliary input control circuit of claim 1, wherein, An electrical isolation unit (300) is provided between the voltage detection module (100) and the switching execution module (200). The first voltage detection unit (110) and the second voltage detection unit (120) are respectively connected to the corresponding first switching unit (210) and second switching unit (220) through the electrical isolation unit (300).

4. The hybrid energy storage inverter auxiliary input control circuit of claim 3, wherein, The electrical isolation unit (300) includes an optocoupler (U1, U3).

5. The hybrid energy storage inverter auxiliary input control circuit of claim 4, wherein, The first switching unit (210) and the second switching unit (220) include relays (K1, K2): The anodes of the light-emitting diodes of the optocouplers (U1, U3) are connected to the auxiliary power source through current-limiting resistors; The cathodes of the light-emitting diodes of the optocouplers (U1, U3) are connected to the output terminals of the first voltage detection unit (110) and the second voltage detection unit (120) respectively. The collector of the phototransistor of the optocoupler (U1, U3) is connected to one end of the corresponding relay (K1, K2); The emitters of the phototransistors in the optocouplers (U1, U3) are grounded.

6. The auxiliary power input control circuit for the hybrid energy storage inverter according to claim 5, characterized in that, The relays (K1, K2) are both normally closed relays.

7. The hybrid energy storage inverter auxiliary input control circuit of claim 2, wherein, The voltage regulator chips (U2, U4) are model TL431.

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