High-voltage integrated cabinet

Abstract

The utility model relates to the technology of high-voltage power equipment, and discloses a high-voltage integrated cabinet, which comprises a high-voltage distribution box, an energy storage converter, an alternating-current isolating switch and the like. The input end of the high-voltage distribution box is connected with a high-voltage battery, and the alternating-current output side is connected to a public power grid to complete energy interaction through the energy storage converter. According to the utility model, the direct current contactor of the high-voltage distribution box, the direct current contactor of the energy storage converter and the direct current soft start circuit are integrated together, so that the repeated cost and the control difficulty are reduced, and the system cost and the soft start time are optimized to a great extent. And finally, on the basis of not influencing the reliability of the system, the soft starting circuit is further optimized by optimizing the starting logic, and the soft starting circuit on the negative electrode side of the battery is removed, so that the cost is further reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of high-voltage electric power equipment, in particular to a high-voltage integrated cabinet. Background Art

[0002] A high-voltage integrated cabinet (i.e., an integrated high-voltage cabinet, or a high-voltage integrated power distribution cabinet) is a device used in a power distribution system, which integrates multiple functional electrical equipment, including a high-voltage distribution box, an energy storage converter, a disconnector, etc., and realizes bidirectional energy flow through the energy storage converter to complete the charging and discharging functions on the battery side. During the startup process of the high-voltage integrated cabinet, due to the presence of DC bus capacitors inside the energy storage converter, the DC contactor is directly attracted, resulting in severe overcurrent. In order to solve this problem, a corresponding soft start circuit needs to be set.

[0003] At present, soft start technology is applied in high-voltage integrated cabinets, and soft start circuits need to be set in both the high-voltage distribution box and the energy storage converter. The repeated design of this soft start circuit will increase the soft start resistance, thereby prolonging the soft start time (of course, the design of multiple soft starts also means that it is necessary to determine whether the soft start is completed multiple times, which will also prolong the soft start time accordingly).

[0004] The above contents are only used to assist in understanding the technical solution of the present utility model and do not constitute an admission that the above contents are prior art. Utility Model Content

[0005] The utility model provides a high-voltage integrated cabinet, aiming to reduce the cost of soft starting of the high-voltage integrated cabinet and reduce the time required for soft starting of the high-voltage integrated cabinet.

[0006] To achieve the above-mentioned purpose, the utility model proposes a high-voltage integrated cabinet, comprising: a high-voltage distribution box, an energy storage converter and an AC isolating switch, wherein the high-voltage distribution box comprises a DC isolating switch and a gating module, one side of the DC isolating switch is used to access the battery side, and the other side is electrically connected to the power conversion unit in the energy storage converter via the gating module; the gating module is provided with a first switch and a first soft start circuit in parallel on the positive line between the DC isolating switch and the power conversion unit, the gating module is provided with a second switch on the negative line between the DC isolating switch and the power conversion unit, and the first soft start circuit is provided with a third switch, a switch tube and a first resistor in sequence in the direction from the DC isolating switch to the power conversion unit; one side of the AC isolating switch is electrically connected to the grid-connected relay in the energy storage converter, and the other side is used to access the external power consumption side; in the energy storage converter, the power conversion unit is electrically connected to the grid-connected relay via the AC filter circuit.

[0007] Optionally, a second soft start circuit is further connected to both sides of the second switch, and the second soft start circuit is provided with a fourth switch and a second resistor in sequence in the direction from the DC isolation switch to the power conversion unit.

[0008] Optionally, the first switch and the first soft start circuit are both electrically connected to the power conversion unit via a first fuse;

[0009] And / or, a second fuse is further provided between the second switch and the power conversion unit.

[0010] Optionally, a DC detection point is further provided on the positive line between the DC isolating switch and the gating module.

[0011] Optionally, a Hall sensor is connected to the DC detection point.

[0012] Optionally, the switch tube is a diode, wherein an anode of the diode is electrically connected to the third switch, and a cathode of the diode is electrically connected to the first resistor.

[0013] Optionally, the high-voltage integrated cabinet further includes a controller, and control output terminals of the controller are electrically connected to the high-voltage distribution box, the energy storage converter and the AC isolating switch, respectively.

[0014] The beneficial effect of the technical solution of the utility model is that it only needs to set a soft start circuit in the high-voltage distribution box to control the soft start of the high-voltage integrated cabinet, which not only reduces the configuration cost of the soft start of the high-voltage integrated cabinet, but also avoids the increase in the soft start time caused by increasing the soft start resistance, that is, the time required for the soft start of the high-voltage integrated cabinet is reduced (and there is no need to perform soft start logic control on the energy storage inverter side, which also reduces the soft start time accordingly), thereby improving the operating efficiency of the high-voltage integrated cabinet. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is a structural schematic diagram of an embodiment of a high-voltage integrated cabinet of the utility model;

[0016] Figure 2 This is a schematic diagram of the startup logic of an embodiment of the high-voltage integrated cabinet of the utility model;

[0017] Figure 3 This is a structural schematic diagram of another embodiment of the high-voltage integrated cabinet of the utility model;

[0018] Figure 4 This is a schematic diagram of the startup logic of another embodiment of the high-voltage integrated cabinet of the utility model.

[0019] The realization of the purpose, functional features and advantages of the utility model will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0020] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the scheme in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0021] It should be noted that all directional indications (such as up, down, left, right, front, back...) in the embodiments of the present invention are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0022] It should also be noted that when an element is referred to as being "fixed on" or "disposed on" another element, it may be directly on the other element or there may be an intermediate element at the same time. When an element is referred to as being "connected to" another element, it may be directly connected to the other element or there may be an intermediate element at the same time.

[0023] In addition, if the description of "first", "second", etc. is involved in the utility model, it is only used for descriptive purposes (such as for distinguishing the same or similar elements), and cannot be understood as indicating or implying its relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in this field to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the utility model.

[0024] The utility model proposes a high-voltage integrated cabinet, referring to Figure 1The high-voltage integrated cabinet includes a high-voltage distribution box, an energy storage converter PCS and an AC disconnector, wherein the high-voltage distribution box includes a DC disconnector and a gating module, one side of the DC disconnector is used to access the battery side, and the other side is electrically connected to the power conversion unit in the energy storage converter PCS through the gating module; the gating module is provided with a first switch K1 and a first soft start circuit in parallel on the positive line between the DC disconnector and the power conversion unit, and the gating module is provided with a second switch K2 on the negative line between the DC disconnector and the power conversion unit, and the first soft start circuit is provided with a third switch K3, a switch tube D and a first resistor R1 in sequence in the direction from the DC disconnector to the power conversion unit; one side of the AC disconnector is electrically connected to the grid-connected relay in the energy storage converter PCS, and the other side is used to access the external power consumption side; in the energy storage converter PCS, the power conversion unit is electrically connected to the grid-connected relay through the AC filter circuit.

[0025] In this embodiment, the DC isolation switch is used to perform electrical isolation between the battery side and the gating module to ensure the safety and reliability of the DC power supply.

[0026] Optionally, a gating module is provided between the DC isolating switch and the power conversion unit to control the flow direction of the current.

[0027] The gating module is provided with a first switch K1 and a first soft start circuit in parallel on the positive line between the DC isolating switch and the power conversion unit.

[0028] Optionally, the first switch K1 is used to control whether the positive electrode of the high-voltage distribution box is connected to the positive electrode of the energy storage converter PCS.

[0029] Optionally, the first soft start circuit is arranged on another branch of the positive line of the gating module; the first soft start circuit includes a third switch K3, a switch tube D and a first resistor R1, and is used to realize a soft start function with gradually increasing current. Among them, the third switch K3 is used to control the start and stop of the first soft start circuit, the switch tube D is used to adjust the current, and the first resistor R1 is used to limit the current change speed to protect the device from overload and power loss.

[0030] Optionally, a power conversion unit is provided in the energy storage inverter PCS for receiving current from the high-voltage distribution box and converting DC power into AC power; the AC side of the power conversion unit is connected to the grid-connected relay after passing through the AC filter circuit.

[0031] Among them, the AC filter circuit is used to stabilize the grid-connected current, improve the power quality, and ensure stable power output; the grid relay is used to control the on and off of each AC branch.

[0032] Optionally, the grid-connected relay is connected to the external power consumption side through an AC isolating switch; wherein the AC isolating switch is used to ensure safe isolation between the energy storage converter PCS and the external power consumption side to protect the external power consumption side equipment.

[0033] Optional, see Figure 2 The following takes the startup logic of the high-voltage integrated cabinet as an example to explain the working process of the high-voltage integrated cabinet:

[0034] First, after the DC isolation switch is turned off, determine whether the DC side insulation test is completed (at this time, the first switch K1, the second switch K2 and the third switch K3 are all disconnected). If not completed, continue the test; if completed, close the second switch K2 and the third switch K3 so that the DC power provided by the battery side can flow to the energy storage converter PCS, and further determine whether the pre-charging of the battery side is completed (which can be determined by the voltage across the first switch K1). The purpose of pre-charging is to charge the battery to an appropriate voltage level before formal startup to reduce the impact during startup and protect the system.

[0035] If the pre-charging on the battery side is not completed, continue to detect until the pre-charging is completed; if the pre-charging on the battery side is completed, the soft start is completed and the first switch K1 is closed. At this time, the power conversion unit performs power conversion output, that is, the high-voltage integrated cabinet officially enters the working state, and can provide AC power to the external power consumption side to achieve efficient energy conversion and distribution.

[0036] In one embodiment, a high-voltage integrated cabinet is provided, which can control the soft start of the high-voltage integrated cabinet only by setting a soft start circuit in the high-voltage distribution box, which not only reduces the configuration cost of the soft start of the high-voltage integrated cabinet, but also avoids the increase in the soft start time caused by increasing the soft start resistance, that is, the time required for the soft start of the high-voltage integrated cabinet is reduced (and there is no need to perform soft start logic control on the energy storage inverter side, which also reduces the soft start time accordingly), thereby improving the operating efficiency of the high-voltage integrated cabinet.

[0037] In one embodiment, based on the above embodiment, referring to Figure 1 or Figure 3 , the first switch K1 is electrically connected to the first resistor R1 and the power conversion unit respectively through the first fuse B1;

[0038] And / or, a second fuse B2 is further provided between the second switch K2 and the power conversion unit.

[0039] In this embodiment, the first switch K1 and the first soft start circuit are electrically connected to the power conversion unit through the first fuse B1, which can provide additional protection measures to prevent damage to the equipment when the circuit is overloaded or short-circuited, thereby enhancing the safety and reliability of the system.

[0040] And / or, a second fuse B2 is further provided between the second switch K2 and the power conversion unit, which can provide additional protection measures to prevent damage to the equipment when the circuit is overloaded or short-circuited, thereby enhancing the safety and reliability of the system.

[0041] The setting of these fuses helps to ensure the long-term stable operation of the high-voltage integrated cabinet.

[0042] In one embodiment, based on the above embodiment, referring to Figure 3 A second soft start circuit is also connected to both sides of the second switch. The second soft start circuit is provided with a fourth switch K4 and a second resistor R2 in sequence in the direction from the DC isolation switch to the power conversion unit.

[0043] In this embodiment, the gating module is provided with a second switch K2 and a second soft start circuit in parallel on the negative line between the DC isolating switch and the power conversion unit.

[0044] Optionally, the second switch K2 is used to control the on / off of one branch of the negative electrode circuit of the gating module to ensure the accuracy of the current flow direction.

[0045] Optionally, the second soft start circuit is arranged on another branch of the negative line of the gating module; the second soft start circuit comprises a fourth switch K4 and a second resistor R2, which are used to realize the soft start function. The fourth switch K4 is used to control the start and stop of the second soft start circuit, and the second resistor R2 is used to limit the current to protect the device from overload and power loss.

[0046] Optional, see Figure 4 The following takes the startup logic of the high-voltage integrated cabinet as an example to explain the working process of the high-voltage integrated cabinet:

[0047] First, after the DC isolation switch is turned off, determine whether the DC side insulation test is completed (at this time, the first switch K1, the second switch K2, the third switch K3 and the fourth switch K4 are all disconnected). If not completed, continue the test; if completed, close the third switch K3 and the fourth switch K4 so that the DC power provided by the battery side can flow to the energy storage converter PCS, and further determine whether the pre-charging of the battery side is completed (which can be determined by the voltage across the first switch K1). The purpose of pre-charging is to charge the battery to an appropriate voltage level before formal startup to reduce the impact during startup and protect the system.

[0048] If the pre-charging on the battery side is not completed, continue to detect until the pre-charging is completed; if the pre-charging on the battery side is completed, the soft start is completed, and the first switch K1 and the second switch K2 are closed. At this time, the power conversion unit performs power conversion output, that is, the high-voltage integrated cabinet officially enters the working state, and can provide AC power to the external power consumption side to achieve efficient energy conversion and distribution.

[0049] In this way, it is also possible to control the soft start of the high-voltage integrated cabinet by simply setting up a soft start circuit in the high-voltage distribution box, thereby reducing the time required for the soft start of the high-voltage integrated cabinet (i.e., there is no need to perform soft start logic control on the energy storage inverter side, which correspondingly reduces the soft start time), thereby improving the operating efficiency of the high-voltage integrated cabinet.

[0050] In one embodiment, based on the above embodiment, the third switch K3 and / or the fourth switch K4 is a switch breaker.

[0051] Optionally, the first switch K1 and / or the second switch K2 is a direct contactor.

[0052] This option can provide a more reliable circuit disconnection function, and can quickly and effectively cut off the current when the circuit needs to be disconnected, thereby ensuring the safety of the system and equipment. Switch circuit breakers usually have fast response and efficient power-off performance, which can effectively deal with various circuit abnormalities and improve the reliability and safety of the system.

[0053] In one embodiment, based on the above embodiment, referring to Figure 1 or Figure 3 A DC detection point J is also provided on the positive line between the DC isolating switch and the gating module. The current value detected by the DC detection point J can be used to determine whether the DC side insulation detection is completed.

[0054] Optionally, the DC detection point J is connected to a Hall sensor. By utilizing the characteristics of the Hall sensor, the current can be measured by detecting the magnetic field, thereby realizing the monitoring of the current in the circuit. The use of the Hall sensor as the access method of the DC detection point J has the advantages of accuracy, fast response and non-contact, can provide reliable current measurement, and will not generate additional load or impact on the circuit. Such a design can effectively enhance the monitoring function of the system, ensure that the abnormal current is detected in time during operation, and further improve the safety and stability of the system.

[0055] In one embodiment, based on the above embodiment, the switch tube D is a diode, wherein the anode of the diode is electrically connected to the third switch K3, and the cathode of the diode is electrically connected to the first resistor R1.

[0056] In this embodiment, when the third switch K3 is closed, the diode is turned on, so that the current in the circuit can flow through the first resistor R1, thereby achieving stable control and management of the circuit. As a choice of the switch tube D, the diode has the characteristics of low cost, simplicity and reliability.

[0057] In one embodiment, based on the above embodiment, the high-voltage integrated cabinet also includes a controller (not shown in the figure), and the control output ends of the controller are electrically connected to the high-voltage distribution box, the energy storage inverter and the AC isolating switch respectively.

[0058] In this embodiment, the control output end of the controller is electrically connected to the high-voltage distribution box, the energy storage converter and the AC isolating switch, respectively. Such a design can realize centralized monitoring and control of each controllable device in the high-voltage integrated cabinet, and improve the intelligence and management efficiency of the system. Through the connection between the output end of the controller and each controllable device, the operator can monitor and adjust the operating status of the high-voltage integrated cabinet in real time, perform fault diagnosis and processing in time, and ensure the stability and safety of the system. The introduction of the controller enables the high-voltage integrated cabinet to have more powerful intelligent control capabilities, which can meet the needs of different scenarios and provide more reliable and convenient power management solutions.

[0059] The above description is only a partial or preferred embodiment of the present invention. Neither the text nor the drawings can limit the scope of protection of the present invention. All equivalent structural changes made by using the contents of the present invention specification and drawings under the overall concept of the present invention, or direct / indirect application in other related technical fields are included in the scope of protection of the present invention.

Claims

1. A high voltage integrated cabinet, characterized in that: include: A high-voltage distribution box, an energy storage converter and an AC isolating switch, wherein the high-voltage distribution box includes a DC isolating switch and a gating module, one side of the DC isolating switch is used to access the battery side, and the other side is connected to the power conversion unit in the energy storage converter via the gating module; the gating module is provided with a first switch and a first soft-start circuit in parallel on the positive line between the DC isolating switch and the power conversion unit, the gating module is provided with a second switch on the negative line between the DC isolating switch and the power conversion unit, and the first soft-start circuit is provided with a third switch, a switch tube and a first resistor in sequence in the direction from the DC isolating switch to the power conversion unit; one side of the AC isolating switch is electrically connected to the grid-connected relay in the energy storage converter, and the other side is used to access the external power consumption side; in the energy storage converter, the power conversion unit is electrically connected to the grid-connected relay via the AC filter circuit.

2. The high voltage integrated cabinet according to claim 1, characterized in that: A second soft start circuit is also connected to both sides of the second switch. The second soft start circuit is provided with a fourth switch and a second resistor in sequence in the direction from the DC isolation switch to the power conversion unit.

3. The high voltage integrated cabinet according to claim 1 or 2, characterized in that: The first switch and the first soft start circuit are both electrically connected to the power conversion unit via a first fuse; And / or, a second fuse is further provided between the second switch and the power conversion unit.

4. The high voltage integrated cabinet according to claim 1, characterized in that: A DC detection point is also provided on the positive line between the DC isolating switch and the gating module.

5. The high voltage integrated cabinet according to claim 4, characterized in that: The DC detection point is connected with a Hall sensor.

6. The high voltage integrated cabinet according to claim 1, characterized in that: The switch tube is a diode, wherein an anode of the diode is electrically connected to the third switch, and a cathode of the diode is electrically connected to the resistor.

7. The high voltage integrated cabinet according to claim 1, characterized in that: The high-voltage integrated cabinet also includes a controller, and control output ends of the controller are electrically connected to the high-voltage distribution box, the energy storage converter and the AC isolating switch respectively.

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