Bus capacitor pre-charging and discharging circuit of energy storage converter
By using a combination of capacitor, first resistor, pre-charge relay and discharge relay in the energy storage converter, efficient pre-charging and discharge are achieved, solving the problems of large resistor size and high cost in the energy storage converter, simplifying the circuit structure and reducing costs.
Patent Information
- Application Number
- CN202520173241.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-24
- Publication Date
- 2026-01-23
- Estimated Expiration
- 2035-01-24
AI Technical Summary
In the existing technology, as the power of a single energy storage converter increases, the number of bus capacitors increases, which in turn increases the size and cost of the pre-charge resistor and the discharge resistor.
A combination of capacitor, first resistor, first pre-charge relay, second pre-charge relay, and first discharge relay is used. Pre-charging and discharge are achieved through the first resistor, reducing the number of resistors and lowering circuit complexity and cost.
It effectively solves the problems of large size and high cost of pre-charge resistors and discharge resistors, simplifies the circuit structure, reduces the number of resistors, and reduces costs.
Smart Images
Figure CN223829236U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of power supply technology, and in particular to a pre-charge and discharge circuit for the bus capacitor of an energy storage converter. Background Technology
[0002] With the development of the energy storage industry, the single-unit power of energy storage converters is gradually increasing. This increase in single-unit power leads to an increase in the number of DC bus capacitors. During power supply, to protect the capacitors and circuits, the capacitors need to be pre-charged before power is supplied and discharged after power is cut off. In related technologies, pre-charging and discharging of the capacitors are achieved by connecting the capacitors to a discharge circuit and a pre-charging circuit respectively, so that they can be charged by connecting to a pre-charging resistor or discharged by connecting to a discharge resistor. As the power increases, the size of the pre-charging resistor and the discharge resistor also increases, resulting in a significant increase in cost. Utility Model Content
[0003] This invention provides a pre-charge and discharge circuit for the bus capacitor of an energy storage converter, which solves the problems of large size and high cost of the pre-charge resistor and discharge resistor in the prior art.
[0004] This utility model provides a bus capacitor pre-charge and discharge circuit for an energy storage converter, comprising: a capacitor, a first resistor, a first pre-charge relay, a second pre-charge relay, and a first discharge relay;
[0005] The capacitor is connected in parallel with the input terminal of the inverter;
[0006] The first terminal of the capacitor is connected to the first terminal of the first resistor, the second terminal of the first resistor is connected to the first terminal of the first pre-charge relay, and the second terminal of the first pre-charge relay is used to connect to the positive terminal of the power supply; the second terminal of the capacitor is connected to the negative terminal of the power supply through the second pre-charge relay; the second terminal of the capacitor is also connected to the second terminal of the first resistor through the first discharge relay.
[0007] The energy storage converter bus capacitor precharge and discharge circuit according to this utility model also includes a first fuse, and the first end of the capacitor is connected to the first resistor through the first fuse.
[0008] The energy storage converter bus capacitor pre-charge and discharge circuit according to this utility model further includes a second resistor and a second discharge relay, and the capacitor includes a first capacitor and a second capacitor connected in series.
[0009] The first terminal of the first capacitor is connected to the first terminal of the first resistor; the second terminal of the first capacitor is connected to the first terminal of the second capacitor, the second terminal of the second capacitor is connected to the first terminal of the second resistor, the second terminal of the second resistor is connected to the first terminal of the second pre-charge relay, and the second terminal of the second pre-charge relay is used to connect to the negative terminal of the power supply; the second terminal of the first capacitor is also connected to the second terminal of the first resistor through the first discharge relay; the first terminal of the second capacitor is also connected to the second terminal of the second resistor through the second discharge relay and the second terminal of the second resistor.
[0010] The energy storage converter bus capacitor precharge and discharge circuit according to this utility model also includes a second fuse, and the second terminal of the second capacitor is connected to the second resistor through the second fuse.
[0011] According to the energy storage converter bus capacitor pre-charge and discharge circuit of this utility model, there are multiple first capacitors and multiple second capacitors.
[0012] Multiple first capacitors are connected in parallel, and multiple second capacitors are connected in parallel.
[0013] The energy storage converter bus capacitor pre-charge and discharge circuit according to this utility model also includes a first disconnect switch and a second disconnect switch;
[0014] The first terminal of the first disconnecting switch is connected to the second terminal of the first pre-charged relay, and the second terminal of the first disconnecting switch is connected to the first terminal of the first resistor.
[0015] The first terminal of the second disconnecting switch is connected to the second terminal of the second precharge relay, and the second terminal of the second disconnecting switch is connected to the first terminal of the second resistor.
[0016] According to the energy storage converter bus capacitor pre-charge and discharge circuit of this utility model, the first disconnect switch and the second disconnect switch are interlocked switches so that the first disconnect switch and the second disconnect switch are closed or opened simultaneously.
[0017] The energy storage converter bus capacitor pre-charge and discharge circuit according to this utility model also includes a control circuit.
[0018] The control circuit includes a control power supply, a pre-charge intermediate relay, and a discharge intermediate relay; the control terminal of the first pre-charge relay and the control terminal of the second pre-charge relay are connected in parallel to form a first control group; the control power supply, the pre-charge intermediate relay, and the first control group are connected in series to form a first control loop.
[0019] The control terminal of the first discharge relay and the control terminal of the second discharge relay are connected in parallel to form a second control group. The control power supply, the discharge intermediate relay and the second control group are connected in series to form a second control loop.
[0020] According to the energy storage converter bus capacitor pre-charge discharge circuit of this utility model, the pre-charge intermediate relay is provided with two first normally closed contacts, two first normally open contacts and a first moving contact. The two first normally closed contacts are arranged in the second control circuit, the two first normally open contacts are arranged in the first control circuit, and the first moving contact is used to selectively conduct the two first normally closed contacts or the two first normally open contacts.
[0021] According to the energy storage converter bus capacitor pre-charge discharge circuit of this utility model, the discharge intermediate relay is provided with two second normally closed contacts, two second normally open contacts and a second moving contact. The two second normally closed contacts are arranged in the first control circuit and the two second normally open contacts are arranged in the second control circuit. The second moving contact is used to selectively conduct the two second normally closed contacts or the two second normally open contacts.
[0022] This utility model discloses a pre-charge and discharge circuit for the bus capacitor of an energy storage converter. A pre-charge circuit is formed by connecting a power supply, a first pre-charge relay, a first resistor, a capacitor, a second pre-charge relay, and a first discharge relay in series. When the pre-charge circuit is activated, the capacitor is charged through the power supply and the first resistor. Simultaneously, the second terminals of the capacitor, the first discharge relay, and the first resistor are connected in series to form a discharge circuit. When the discharge circuit is activated, the capacitor is discharged through the first resistor. The first pre-charge relay, the second pre-charge relay, and the first discharge relay work together to switch between the discharge circuit and the pre-charge circuit. As can be seen from the above, the pre-charge and discharge circuit of the energy storage converter bus capacitor of this utility model, through the cooperation and switching of the capacitor, the first resistor, the first pre-charge relay, the second pre-charge relay and the first discharge relay, enables both pre-charging and discharge to be carried out through the first resistor, reducing the number of resistors required for the capacitor pre-charge and discharge circuits, and effectively solving the defects of large size and high cost of pre-charge resistor and discharge resistor in the prior art. Attached Figure Description
[0023] To more clearly illustrate the technical solutions in this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.
[0024] Figure 1 This is a schematic diagram of the pre-charge and discharge circuit of the bus capacitor of the energy storage converter provided in this embodiment of the utility model.
[0025] Figure 2 This is a schematic diagram showing the pre-charge circuit of the pre-charge discharge circuit of the energy storage converter bus capacitor provided in this embodiment of the utility model.
[0026] Figure 3 This is a schematic diagram showing the conduction of the discharge circuit of the first capacitor in the pre-charge discharge circuit of the energy storage converter bus capacitor provided in this embodiment of the utility model.
[0027] Figure 4 This is a schematic diagram showing the conduction of the discharge circuit of the second capacitor in the pre-charge discharge circuit of the energy storage converter bus capacitor provided in this embodiment of the utility model.
[0028] Figure 5 This is a schematic diagram of the control circuit provided in an embodiment of the present invention.
[0029] Figure label:
[0030] 100. Pre-charge and discharge circuit for the bus capacitor of the energy storage converter;
[0031] 101. First resistor; 102. First pre-charge relay; 103. Second pre-charge relay; 104. First discharge relay; 105. First fuse; 106. Second resistor; 107. Second discharge relay; 108. First capacitor; 109. Second capacitor; 110. Second fuse; 111. First disconnecting switch; 112. Second disconnecting switch.
[0032] 200. Control circuit; 201. Control power supply; 202. Pre-charge intermediate relay; 2021. First normally closed contact; 2022. First normally open contact; 203. Discharge intermediate relay; 2031. Second normally closed contact; 2032. Second normally open contact. Detailed Implementation
[0033] To make the objectives, technical solutions, and advantages 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. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.
[0034] The following is combined Figures 1-5 This invention describes the pre-charge and discharge circuit of the bus capacitor in an energy storage converter.
[0035] likeFigures 1 to 4 As shown, this utility model provides a bus capacitor pre-charge and discharge circuit 100 for an energy storage converter, including: a capacitor, a first resistor 101, a first pre-charge relay 102, a second pre-charge relay 103, and a first discharge relay 104. The capacitor is connected in parallel with the input terminal of the inverter. The first terminal of the capacitor is connected to the first terminal of the first resistor 101, and the second terminal of the first resistor 101 is connected to the first terminal of the first pre-charge relay 102. The second terminal of the first pre-charge relay 102 is connected to the positive terminal of the power supply. The second terminal of the capacitor is connected to the negative terminal of the power supply through the second pre-charge relay 103. The second terminal of the capacitor is also connected to the second terminal of the first resistor 101 through the first discharge relay 104.
[0036] In this embodiment, the first terminal of the capacitor is connected to the positive terminal of the power supply via a first resistor 101 and a first pre-charge relay 102, and the second terminal of the capacitor is connected to the negative terminal of the power supply via a second pre-charge relay 103. It can be understood that the first and second terminals of the first pre-charge relay 102 can switch between an on and off state to control the continuity of the circuit between the power supply and the first resistor 101; similarly, the first and second terminals of the second pre-charge relay 103 can switch between an on and off state to control the continuity of the circuit between the power supply and the capacitor. When both the first and second pre-charge relays 102 and 103 are on, the power supply, the first pre-charge relay 102, the first resistor 101, the capacitor, the second pre-charge relay 103, and the first discharge relay 104 can be connected in series to form a pre-charge circuit (e.g., ...). Figure 2 (as shown by the thick solid line with arrows) so that the capacitor can be pre-charged through the first resistor 101.
[0037] Simultaneously, by sequentially connecting the second terminal of the capacitor, the second terminal of the first discharge relay 104, and the second terminal of the first discharge relay 104, the first and second terminals of the first discharge relay 104 can switch between an on and off state to control the continuity of the circuit between the second terminal of the capacitor and the first resistor 101. When both the first pre-charge relay 102 and the second pre-charge relay 103 are off, and the first discharge relay 104 is on, the capacitor, the first discharge relay 104, and the first resistor 101 can be connected in series to form a discharge circuit (e.g., Figure 3 (As shown by the thick solid line with arrows), so that the capacitor can discharge through the first resistor 101. It is understood that when the capacitor needs to be pre-charged, the first and second terminals of the first discharge relay 104 need to be switched to the off state to avoid short circuit.
[0038] The energy storage converter bus capacitor pre-charge and discharge circuit 100 of this invention forms a pre-charge circuit by sequentially connecting a power supply, a first pre-charge relay 102, a first resistor 101, a capacitor, a second pre-charge relay 103, and a first discharge relay 104 in series. When the pre-charge circuit is activated, the capacitor is charged through the power supply and the first resistor 101. Simultaneously, the second terminal of the capacitor, the second terminal of the first discharge relay 104, and the second terminal of the first resistor 101 are sequentially connected, forming a discharge circuit. When the discharge circuit is activated, the capacitor is discharged through the first resistor 101. The first pre-charge relay 102, the second pre-charge relay 103, and the first discharge relay 104 cooperate to switch between the discharge circuit and the pre-charge circuit. As can be seen from the above, the energy storage converter bus capacitor precharge and discharge circuit 100 of this utility model, through the cooperative connection and switching of the capacitor, the first resistor 101, the first precharge relay 102, the second precharge relay 103 and the first discharge relay 104, enables both precharge and discharge to be carried out through the first resistor 101, reducing the number of resistors required for the capacitor precharge and discharge circuits, and effectively solving the defects of large size and high cost of precharge resistors and discharge resistors in the prior art.
[0039] In some embodiments, such as Figures 1 to 4 As shown, the pre-charge and discharge circuit 100 of the energy storage converter bus capacitor also includes a first fuse 105, and the first end of the capacitor is connected to the first resistor 101 through the first fuse 105.
[0040] In this embodiment, a first fuse 105 is provided between the capacitor and the first resistor 101. The first fuse 105 is used to melt after the pre-charge circuit or discharge circuit is connected and the current in the circuit exceeds a specified value for a period of time, so as to avoid excessive current in the circuit and damage to various components.
[0041] In some embodiments, such as Figures 1 to 4 As shown, the energy storage converter bus capacitor pre-charge and discharge circuit 100 also includes a second resistor 106 and a second discharge relay 107. The capacitors include a first capacitor 108 and a second capacitor 109 connected in series. The first terminal of the first capacitor 108 is connected to the first terminal of the first resistor 101. The second terminal of the first capacitor 108 is connected to the first terminal of the second capacitor 109, the second terminal of the second capacitor 109 is connected to the first terminal of the second resistor 106, and the second terminal of the second resistor 106 is connected to the first terminal of the second pre-charge relay 103. The second terminal of the second pre-charge relay 103 is used to connect to the negative terminal of the power supply. The second terminal of the first capacitor 108 is also connected to the second terminal of the first resistor 101 through a first discharge relay 104. The first terminal of the second capacitor 109 is also connected to the second terminal of the second resistor 106 through the second discharge relay 107.
[0042] In this embodiment, by setting the capacitors as a first capacitor 108 and a second capacitor 109 connected in series, the first capacitor 108 and the second capacitor 109 can cooperate with other components to form their respective pre-charge circuits and discharge circuits, so as to pre-charge and discharge the first capacitor 108 and the second capacitor 109.
[0043] Specifically, the positive terminal of the power supply, the first pre-charge relay 102, the first resistor 101, the first capacitor 108, the second capacitor 109, the second resistor 106, the second pre-charge relay 103, and the negative terminal of the power supply are connected in series to form a pre-charge circuit (e.g., Figure 2 (As shown by the thick solid line with arrows in the middle), when the first precharge relay 102 and the second precharge relay 103 are kept on, the precharge circuit can precharge the first capacitor 108 and the second capacitor 109 through the first resistor 101 and the second resistor 106.
[0044] Simultaneously, by sequentially connecting the second terminal of the first capacitor 108, the first discharge relay 104, and the second terminal of the first resistor 101, the first capacitor 108, the first discharge relay 104, and the first resistor 101 are connected in series to form the discharge circuit of the first capacitor 108 (e.g., Figure 3 (As shown by the thick solid line with arrows in the middle), when the first precharge relay 102 and the second precharge relay 103 are disconnected and the first discharge relay 104 is connected, the discharge circuit can discharge the first capacitor 108 through the first resistor 101.
[0045] Similarly, the first terminal of the second capacitor 109, the second discharge relay 107, and the second terminal of the second resistor 106 are connected in sequence, so that the second capacitor 109, the second discharge relay 107, and the second resistor 106 are connected in series to form the discharge circuit of the second capacitor 109 (e.g., Figure 4 (As shown by the thick solid line with arrows in the middle), when the first precharge relay 102 and the second precharge relay 103 are disconnected and the second discharge relay 107 is connected, the discharge circuit can discharge the second capacitor 109 through the second resistor 106.
[0046] It is understood that in some embodiments, such as Figures 1 to 4 As shown, the pre-charge and discharge circuit 100 of the energy storage converter bus capacitor also includes a second fuse 110, and the second terminal of the second capacitor 109 is connected to the second resistor 106 through the second fuse 110.
[0047] In this embodiment, a second fuse 110 is provided between the second capacitor 109 and the second resistor 106. The second fuse 110 is used to melt after the pre-charging circuit or the discharge circuit of the second capacitor 109 is connected and the current in the circuit exceeds a specified value for a period of time, so as to avoid excessive current in the circuit and damage to various components.
[0048] It is understandable that a first fuse 105 can be provided between the first terminal of the first capacitor 108 and the first resistor 101.
[0049] In some embodiments, such as Figures 1 to 4 As shown, there are multiple first capacitors 108 and multiple second capacitors 109. Multiple first capacitors 108 are connected in parallel, and multiple second capacitors 109 are connected in parallel.
[0050] In this embodiment, by connecting multiple first capacitors 108 in parallel and multiple second capacitors 109 in parallel, the pre-charging circuit can simultaneously pre-charge all first capacitors 108 and all second capacitors 109 when it is turned on. When the discharge circuit of the first capacitor 108 is turned on, it can simultaneously discharge all first capacitors 108, and when the discharge circuit of the second capacitor 109 is turned on, it can simultaneously discharge all second capacitors 109.
[0051] In some embodiments, such as Figures 1 to 4 As shown, the pre-charge discharge circuit 100 of the energy storage converter bus capacitor also includes a first disconnect switch 111 and a second disconnect switch 112. The first terminal of the first disconnect switch 111 is connected to the second terminal of the first pre-charge relay 102, and the second terminal of the first disconnect switch 111 is connected to the first terminal of the first resistor 101. The first terminal of the second disconnect switch 112 is connected to the second terminal of the second pre-charge relay 103, and the second terminal of the second disconnect switch 112 is connected to the first terminal of the second resistor 106.
[0052] In this embodiment, by connecting the two ends of the first disconnect switch 111 to the second end of the first pre-charge relay 102 and the first end of the first resistor 101 respectively, that is, by connecting the two ends of the first disconnect switch 111 to the positive terminal of the power supply and the first end of the first capacitor 108 respectively, when the first disconnect switch 111 is closed, the positive terminal of the power supply is directly connected to the first end of the first capacitor 108. Similarly, when the second disconnect switch 112 is closed, the negative terminal of the power supply is directly connected to the second end of the second capacitor 109, so that the power supply can supply power to the input terminal of the inverter through the first capacitor 108 and the second capacitor 109. At the same time, when the first disconnect switch 111 and the second disconnect switch 112 are open, the power supply is not directly connected to the first capacitor 108 and the second capacitor 109, and it will not affect the pre-charge circuit and the discharge circuit. The user can still pre-charge and discharge the first capacitor 108 and the second capacitor 109 through the first pre-charge relay 102, the second pre-charge relay 103, the first discharge relay 104 and the second discharge relay 107.
[0053] In some embodiments, such as Figures 1 to 4 As shown, the first disconnecting switch 111 and the second disconnecting switch 112 are interlocked switches, so that the first disconnecting switch 111 and the second disconnecting switch 112 are closed or opened simultaneously.
[0054] In this embodiment, by interlocking the first disconnect switch 111 and the second disconnect switch 112, the closed or open states of the first disconnect switch 111 and the second disconnect switch 112 can be kept consistent, so that the user can operate when turning the inverter on and off.
[0055] In some embodiments, such as Figure 5 As shown, the pre-charge and discharge circuit 100 of the energy storage converter bus capacitor also includes a control circuit 200. The control circuit 200 includes a control power supply 201, a pre-charge intermediate relay 202, and a discharge intermediate relay 203. The control terminals of the first pre-charge relay 102 and the second pre-charge relay 103 are connected in parallel to form a first control group. The control power supply 201, the pre-charge intermediate relay 202, and the first control group are connected in series to form a first control loop. The control terminals of the first discharge relay 104 and the second discharge relay 107 are connected in parallel to form a second control group. The control power supply 201, the discharge intermediate relay 203, and the second control group are connected in series to form a second control loop.
[0056] In this embodiment, a first control group is formed by connecting the control terminals of the first pre-charge relay 102 and the second pre-charge relay 103 in parallel to synchronously control the first pre-charge relay 102 and the second pre-charge relay 103. It is understood that by switching the control terminals of the relays on and off, the position of the moving contact of the relay can be controlled, so that the moving contact connects with the normally open or normally closed contact, thereby controlling the on / off state of the corresponding circuit. The control power supply 201, the pre-charge intermediate relay 202, and the first control group are connected in series to form a first control circuit. The pre-charge intermediate relay 202 is used to control the on / off state of the first control circuit, thereby achieving synchronous control of the first pre-charge relay 102 and the second pre-charge relay 103, so that the pre-charge circuit is turned on or off. Similarly, the discharge intermediate relay 203 is used to control the on / off state of the second control circuit, thereby achieving synchronous control of the first discharge relay 104 and the second discharge relay 107, so that the discharge circuit is turned on or off.
[0057] In some embodiments, the precharge intermediate relay 202 is provided with two first normally closed contacts 2021, two first normally open contacts 2022 and a first moving contact (not shown in the figure). The two first normally closed contacts 2021 are disposed in the second control circuit, the two first normally open contacts 2022 are disposed in the first control circuit, and the first moving contact is used to selectively conduct the two first normally closed contacts 2021 or the two first normally open contacts 2022.
[0058] In this embodiment, the two first normally closed contacts 2021 of the pre-charge intermediate relay 202 are used to cooperate with the discharge intermediate relay 203 to control the conduction of the second control circuit; the two first normally open contacts 2022 are used to control the conduction of the first control circuit. The first moving contact of the pre-charge intermediate relay 202 can move between the first normally closed contact 2021 and the first normally open contact 2022 under the control of its own control circuit. When the first moving contact moves between the two first normally open contacts 2022, the two first normally open contacts 2022 conduct, thereby conducting the first control circuit, which in turn controls the first pre-charge relay 102 and the second pre-charge relay 103 to conduct the pre-charge circuit, so as to pre-charge the capacitor. Furthermore, since the first moving contact can only conduct one pair of contacts at a time, it avoids the first control circuit and the second control circuit from conducting simultaneously, thereby avoiding the simultaneous conduction of the pre-charge circuit and the discharge circuit, which could cause a short circuit fault.
[0059] Furthermore, in some embodiments, the discharge intermediate relay 203 is provided with two second normally closed contacts 2031, two second normally open contacts 2032, and a second moving contact. The two second normally closed contacts 2031 are disposed in the first control circuit, the two second normally open contacts 2032 are disposed in the second control circuit, and the second moving contact is used to selectively conduct the two second normally closed contacts 2031 or the two second normally open contacts 2032.
[0060] In this embodiment, the two second normally closed contacts 2031 of the discharge intermediate relay 203 are used to cooperate with the two first normally open contacts 2022 of the precharge intermediate relay 202 to control the conduction of the first control circuit, and the two second normally open contacts 2032 are used to cooperate with the two first normally closed contacts 2021 of the precharge intermediate relay 202 to control the conduction of the second control circuit. The second moving contact of the discharge intermediate relay 203 can move between the second normally closed contact 2031 and the second normally open contact 2032 under the control of its own control terminal circuit. When the second moving contact moves between the two second normally open contacts 2032, the two second normally open contacts 2032 are turned on. When the precharge intermediate relay 202 is not triggered and its first normally closed contact 2021 remains on, the second control circuit is turned on, thereby controlling the first discharge relay 104 and the second discharge relay 107 to turn on the two discharge circuits so as to discharge the first capacitor 108 and the second capacitor 109 respectively. In addition, since the second moving contact can only conduct one pair of contacts at a time, it avoids the first control circuit and the second control circuit from conducting simultaneously, thereby avoiding the pre-charge circuit and the discharge circuit from conducting simultaneously and causing a short circuit fault.
[0061] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and not to limit it. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this utility model.
Claims
1. A pre-charge and discharge circuit for the bus capacitor of an energy storage converter, characterized in that, include: Capacitor, first resistor, first pre-charge relay, second pre-charge relay, first discharge relay; The capacitor is connected in parallel with the input terminal of the inverter; The first terminal of the capacitor is connected to the first terminal of the first resistor, the second terminal of the first resistor is connected to the first terminal of the first pre-charge relay, and the second terminal of the first pre-charge relay is used to connect to the positive terminal of the power supply; the second terminal of the capacitor is connected to the negative terminal of the power supply through the second pre-charge relay; the second terminal of the capacitor is also connected to the second terminal of the first resistor through the first discharge relay.
2. The pre-charge and discharge circuit for the bus capacitor of the energy storage converter according to claim 1, characterized in that, It also includes a first fuse, and the first terminal of the capacitor is connected to the first resistor through the first fuse.
3. The pre-charge and discharge circuit for the bus capacitor of the energy storage converter according to claim 1, characterized in that, It also includes a second resistor and a second discharge relay, and the capacitor includes a first capacitor and a second capacitor connected in series; The first terminal of the first capacitor is connected to the first terminal of the first resistor; the second terminal of the first capacitor is connected to the first terminal of the second capacitor, the second terminal of the second capacitor is connected to the first terminal of the second resistor, the second terminal of the second resistor is connected to the first terminal of the second pre-charge relay, and the second terminal of the second pre-charge relay is used to connect to the negative terminal of the power supply; the second terminal of the first capacitor is also connected to the second terminal of the first resistor through the first discharge relay; the first terminal of the second capacitor is also connected to the second terminal of the second resistor through the second discharge relay and the second terminal of the second resistor.
4. The pre-charge and discharge circuit for the bus capacitor of the energy storage converter according to claim 3, characterized in that, It also includes a second fuse, and the second terminal of the second capacitor is connected to the second resistor through the second fuse.
5. The pre-charge and discharge circuit for the bus capacitor of the energy storage converter according to claim 3, characterized in that, There are multiple of both the first capacitor and the second capacitor; Multiple first capacitors are connected in parallel, and multiple second capacitors are connected in parallel.
6. The pre-charge and discharge circuit for the bus capacitor of the energy storage converter according to claim 3, characterized in that, It also includes a first disconnect switch and a second disconnect switch; The first terminal of the first disconnecting switch is connected to the second terminal of the first pre-charged relay, and the second terminal of the first disconnecting switch is connected to the first terminal of the first resistor. The first terminal of the second disconnecting switch is connected to the second terminal of the second precharge relay, and the second terminal of the second disconnecting switch is connected to the first terminal of the second resistor.
7. The pre-charge and discharge circuit for the bus capacitor of the energy storage converter according to claim 6, characterized in that, The first disconnect switch and the second disconnect switch are interlocked switches, so that the first disconnect switch and the second disconnect switch are closed or opened simultaneously.
8. The pre-charge and discharge circuit for the bus capacitor of the energy storage converter according to claim 3, characterized in that, It also includes control circuitry; The control circuit includes a control power supply, a pre-charge intermediate relay, and a discharge intermediate relay; the control terminal of the first pre-charge relay and the control terminal of the second pre-charge relay are connected in parallel to form a first control group; the control power supply, the pre-charge intermediate relay, and the first control group are connected in series to form a first control loop. The control terminal of the first discharge relay and the control terminal of the second discharge relay are connected in parallel to form a second control group. The control power supply, the discharge intermediate relay and the second control group are connected in series to form a second control loop.
9. The pre-charge and discharge circuit for the bus capacitor of the energy storage converter according to claim 8, characterized in that, The pre-charge intermediate relay has two first normally closed contacts, two first normally open contacts, and a first moving contact. The two first normally closed contacts are located in the second control circuit, and the two first normally open contacts are located in the first control circuit. The first moving contact is used to selectively connect the two first normally closed contacts or the two first normally open contacts.
10. The pre-charge and discharge circuit for the bus capacitor of the energy storage converter according to claim 9, characterized in that, The discharge intermediate relay is provided with two second normally closed contacts, two second normally open contacts, and a second moving contact. The two second normally closed contacts are located in the first control circuit, and the two second normally open contacts are located in the second control circuit. The second moving contact is used to selectively connect the two second normally closed contacts or the two second normally open contacts.