Data center diesel generating set grounding device

Abstract

The utility model relates to the technical field of generator protection, in particular to a data center diesel generating set grounding device. The neutral point of the generator is connected with the public grounding resistor through the vacuum contactor, and the control circuit comprises a change-over switch; the remote control contact is connected with the remote switching side of the change-over switch in an on-off controllable manner; the local control switch is connected with the local switching side of the change-over switch in a controllable on-off manner; a coil of the vacuum contactor is connected to the ends, away from the change-over switch, of the remote control contact and the local control switch, the coil is powered on based on conduction of the remote control contact or the local control switch, and the vacuum contactor is closed. According to the technical scheme of the utility model, the change-over switch, the remote control contact and the local control switch are arranged, so that various local and remote control modes of the vacuum contactor are realized.

Description

Technical Field

[0001] This utility model relates to the field of generator protection technology, specifically to a grounding device for a data center diesel generator set. Background Technology

[0002] A diesel generator set is an internal combustion engine that uses diesel fuel. Diesel engines are compression ignition engines, often referred to as Diesel engines after their principal inventor, Rudolf Diesel. When a diesel engine is running, air is drawn into the cylinders and compressed to a high temperature of 500–700°C due to the piston's movement. Fuel is then injected as a mist into the hot air, mixing to form a combustible mixture that ignites automatically. The energy released during combustion acts on the piston crown, pushing the piston and converting it into rotational mechanical work via the connecting rod and crankshaft. This mechanical energy is then converted into electrical energy.

[0003] Diesel generator sets are widely used both domestically and internationally, especially as crucial backup emergency power for large data centers. Protecting diesel generator sets from damage during operation is a major challenge. Current technologies typically use grounding to protect these sets, but existing grounding systems often have limited control methods. Most systems only offer local manual control and lack remote control capabilities. In applications like large data centers, when emergencies require remote operation of the generator grounding system, the inability of operators to intervene promptly could lead to further equipment failure. Utility Model Content

[0004] The purpose of this utility model is to provide a grounding device for a data center diesel generator set, thereby solving the above-mentioned technical problems;

[0005] The technical problem solved by this utility model can be achieved by the following technical solution:

[0006] A grounding device for a data center diesel generator set, wherein the neutral point of the generator is connected to a common grounding resistor via a vacuum contactor, the vacuum contactor being controllably switched on and off via a control circuit, the control circuit comprising...

[0007] Changeover switch;

[0008] A remote control contact is connected to the remote switching side of the changeover switch in a controllable manner.

[0009] A local control switch is provided to control the on / off connection of the local switching side of the changeover switch;

[0010] The coil of the vacuum contactor is connected to the end of the remote control contact and the local control switch away from the changeover switch. When the remote control contact or the local control switch is turned on, the coil is energized and the vacuum contactor is closed.

[0011] Preferably, the local control switch includes,

[0012] A normally closed local trip switch, wherein the first end of the local trip switch is connected to the local switching side of the transfer switch;

[0013] A normally open local closing switch is provided, with its first terminal connected to the second terminal of the local opening switch, and the second terminal of the local closing switch connected to the coil. When the local closing switch is closed, the coil is energized, and the vacuum contactor remains engaged.

[0014] Preferred options also include,

[0015] A current transformer is connected to the end of the common grounding resistor furthest from the vacuum contactor.

[0016] An overcurrent relay is connected to the secondary side of the current transformer.

[0017] Preferably, it also includes a closing indicator, which includes a closing indicator light connected to the vacuum contactor, which illuminates when the vacuum contactor is closed.

[0018] Preferably, it also includes a tripping indicator, which includes a tripping indicator light connected to the vacuum contactor, which illuminates when the vacuum contactor is disconnected.

[0019] Preferably, it also includes a control power supply, and the control circuit is connected to the control power supply via a DC power switch.

[0020] Preferably, the generator is housed in a cabinet and also includes a temperature and humidity controller for controlling the temperature and humidity inside the cabinet. The temperature and humidity controller is connected to the temperature and humidity sensor inside the cabinet and is connected to the control power supply via an AC power switch.

[0021] Preferably, it further includes a signal transmission unit connected to the vacuum contactor, which transmits on / off signals based on the on / off state of the vacuum contactor.

[0022] Preferably, the common grounding resistor comprises a plurality of resistors connected in series.

[0023] Preferably, the front side of the cabinet is provided with a control panel, and both the changeover switch and the local control switch are located on the control panel.

[0024] The beneficial effects of this utility model are as follows: By adopting the above technical solution, this utility model achieves multiple control methods for the vacuum contactor, including local and remote control, through the setting of a changeover switch, remote control contacts, and local control switches. Whether in daily operation or in emergency situations, operators can flexibly choose the control method and promptly operate the unit's grounding system to ensure equipment safety. Attached Figure Description

[0025] Figure 1 This is a circuit diagram of the neutral point grounding of the generator in an embodiment of this utility model;

[0026] Figure 2 This is a schematic diagram of the control circuit in an embodiment of the present invention;

[0027] Figure 3 This is a schematic diagram of the circuit of the closing indicator in an embodiment of this utility model;

[0028] Figure 4 This is a schematic diagram of the circuit of the trip indicator in an embodiment of this utility model;

[0029] Figure 5 This is a schematic diagram of the temperature and humidity controller circuit in an embodiment of this utility model;

[0030] Figure 6 This is a schematic diagram of the signal transmission unit circuit in an embodiment of the present invention;

[0031] Figure 7 This is a cross-sectional view of the cabinet interior in an embodiment of this utility model;

[0032] Figure 8 This is a schematic diagram of the front side of the cabinet in an embodiment of this utility model;

[0033] Figure 9 This is a schematic diagram of the common grounding resistor for multiple generators in an embodiment of this utility model.

[0034] In the attached diagram: G, generator; P1, generator neutral point; KM, vacuum contactor; DK1, DC power switch; DK2, AC power switch; R, common grounding resistor; CT, current transformer; KA, overcurrent relay; LW, changeover switch; P2, remote control contact; SA, local trip switch; SB, local close switch; KM1, coil; LR, closing indicator light; LG, trip indicator light; WK, temperature and humidity controller; W1, temperature and humidity sensor; K1, signal transmission unit. Detailed Implementation

[0035] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0036] It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other.

[0037] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, but this is not intended to limit the present invention.

[0038] A grounding device for a data center diesel generator set, such as Figures 1 to 9 As shown, the device includes a cabinet containing several generators G. The neutral point P1 of each generator G is controllably connected to a common grounding resistor R via a vacuum contactor KM. The cabinet also contains a control circuit for the vacuum contactor KM, which includes...

[0039] Changeover switch LW;

[0040] The remote control contact P2 can control the on / off connection of the remote switching side of the changeover switch LW;

[0041] The local control switch can control the on / off connection of the local switching side of the transfer switch LW;

[0042] The coil KM1 of the vacuum contactor KM is connected to the remote control contact P2 and the end of the local control switch away from the changeover switch LW. When either the remote control contact P2 or the local control switch is turned on, the coil KM1 is energized, and the vacuum contactor KM closes.

[0043] Specifically, such as Figure 2 As shown, this utility model enables multiple control methods for the vacuum contactor KM through a changeover switch LW, a remote control contact P2, and a local control switch. It can be operated locally via the local control switch or remotely controlled via the remote control contact P2, offering flexible and convenient operation to adapt to different work scenarios.

[0044] For a three-phase four-wire high-voltage generator G, the N line cannot be directly grounded. It must be connected to the grounding point through a vacuum contactor (KM) and a resistor to limit the current value during a grounding fault.

[0045] During a single-phase ground fault, the generator G may overheat and be damaged within a very short time (1 to 3 seconds). The generator G can be protected by grounding through a grounding resistor to limit the short-circuit current of the single-phase ground fault, while also extending the duration of the short-circuit current to achieve selective protection.

[0046] This invention limits the fault current to 100A for 10 seconds. This allows the power system time for detection, diagnosis, protection, and switching, thereby preventing potential damage to line equipment.

[0047] However, in low-voltage systems, a resistor is often used for the neutral point P1 because low-voltage systems generally have single-phase loads. If the neutral point P1 is grounded through a resistor, it will be impossible to supply power to the single-phase load.

[0048] In a multi-unit parallel operation system, a common grounding resistor R can be used. The neutral point P1 of all units must be connected to the common grounding resistor R via a high-voltage vacuum contactor KM, with automatic closing and opening control. When the units are operating in parallel, only one generator G's neutral point P1 can be connected to the common grounding resistor R via the closed high-voltage vacuum contactor KM. The high-voltage vacuum contactors KM of the remaining operating units and non-operating units are disconnected from the grounding resistor. Figure 9 As shown.

[0049] The grounding resistance value is calculated as follows:

[0050] R = V / (1.732 x I);

[0051] R: Grounding resistance, Ohms;

[0052] V: Rated output voltage of generator G, in V;

[0053] I: Maximum single-phase ground fault current limit, A (generally taken as 100A);

[0054] Assume the diesel generator set has a power of 2000KW, 50Hz, and 10.5KV;

[0055] Calculate based on the above instructions:

[0056] R = V / (1.732 x I)

[0057] R: Grounding resistance, Ohms;

[0058] V: Rated output voltage of generator G, V = 10.5KV;

[0059] I: Maximum single-phase ground fault current limit, A = 100A;

[0060] Calculation shows that R = 60.6Ω, with a value of 60.6Ω ± 5%.

[0061] In a preferred embodiment, such as Figure 2 As shown, the local control switch includes,

[0062] The normally closed local trip switch SA is connected at its first end to the local switching side of the changeover switch LW.

[0063] The normally open local closing switch SB has its first terminal connected to the second terminal of the local opening switch SA. The second terminal of the local closing switch SB is connected to the coil KM1. When the local closing switch SB is closed, the coil KM1 is energized, and the vacuum contactor KM remains engaged.

[0064] With the increasing T4 level of data centers and the higher construction standards required for big data centers, more than 100 data centers are built every year, and each data center must be equipped with more than 10 grounding systems. Therefore, the grounding device for data center diesel generator sets provided by this utility model is necessary and feasible.

[0065] In a preferred embodiment, such as Figure 1 As shown, it also includes,

[0066] The current transformer CT is connected to the end of the common grounding resistor R that is furthest from the vacuum contactor KM.

[0067] The overcurrent relay KA is connected to the secondary side of the current transformer CT.

[0068] Specifically, traditional diesel generator set grounding systems often lack effective overcurrent protection devices. When a grounding system fault causes excessive current, the circuit cannot be cut off in time, which can easily lead to overheating and damage to the generator G.

[0069] This invention incorporates a current transformer (CT) and an overcurrent relay (KA) to monitor the current in the common grounding resistor R in real time. When an overcurrent occurs, the overcurrent relay (KA) activates quickly, cutting off the circuit and protecting the equipment.

[0070] In a preferred embodiment, such as Figure 3 As shown, it also includes a closing indicator, which includes a closing indicator light LR connected to the vacuum contactor KM, which illuminates when the vacuum contactor KM is closed.

[0071] In a preferred embodiment, such as Figure 4 As shown, it also includes a trip indicator, which includes a trip indicator light LG connected to the vacuum contactor KM, which illuminates when the vacuum contactor KM is disconnected.

[0072] Specifically, the closing and opening indicators visually display the operating status of the vacuum contactor KM via the closing indicator light LR and the opening indicator light LG. Operators can quickly determine the continuity of the grounding system using these indicator lights.

[0073] In a preferred embodiment, such as Figure 2 As shown, it also includes a control power supply, and the control circuit is connected to the control power supply through a DC power switch DK1.

[0074] In this invention, the control power supply is an AC220V uninterruptible power supply.

[0075] In a preferred embodiment, such as Figure 5 As shown, it also includes a temperature and humidity controller WK for controlling the temperature and humidity inside the cabinet. The temperature and humidity controller WK is connected to the temperature and humidity sensor W1 inside the cabinet, and the temperature and humidity controller WK is connected to the control power supply through the AC power switch DK2.

[0076] Specifically, the temperature and humidity controller WK is connected to the temperature and humidity sensor W1 inside the cabinet and is connected to the control power supply through the AC power switch DK2, which can effectively control the temperature and humidity inside the cabinet and extend the service life of the equipment.

[0077] In a preferred embodiment, such as Figure 6 As shown, it also includes a signal transmission unit K1, which is connected to a vacuum contactor KM and transmits on / off signals based on the on / off state of the vacuum contactor KM.

[0078] Specifically, external systems such as external monitoring systems and management systems obtain the on / off status of the vacuum contactor KM through the signal transmission unit K1, thereby monitoring and managing the operation status of the entire grounding system.

[0079] In a preferred embodiment, the common grounding resistor R includes a plurality of resistors connected in series on the inside of the cabinet.

[0080] In this utility model, according to the required resistance value of the public grounding resistor R, a resistor sheet that meets the requirements after being connected in series is selected. The resistor sheet is made of high-quality stainless steel material, which has high conductivity, high temperature coefficient, can withstand high temperature of up to 1400℃, is corrosion resistant, and has good stability.

[0081] This utility model can be equipped with an intelligent monitoring and protection device for resistor cabinets, which can record the magnitude of single-phase grounding current, grounding time, resistor temperature, ambient temperature and humidity, and number of grounding actions; it also has a 485 communication interface, which can transmit the detected and recorded information to the main control room.

[0082] Data centers often use a single resistor shared by multiple generator sets, used in conjunction with a grounding switch cabinet, to interlock the vacuum contactors (KM) of multiple diesel generator sets. If interlocking is required within this cabinet, a PLC (Programmable Logic Controller) can be added.

[0083] In a preferred embodiment, such as Figure 8 As shown, a control panel is located on the front side of the cabinet, with the selector switch LW and the local control switch both located on the control panel.

[0084] Specifically, the control panel also includes a closing indicator light LR, a tripping indicator light LG, a temperature and humidity controller WK, and overcurrent stage electrical components.

[0085] The above description is only a preferred embodiment of the present utility model and does not limit the implementation method and protection scope of the present utility model. Those skilled in the art should realize that all solutions obtained by equivalent substitutions and obvious changes made based on the description and illustrations of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A grounding device for a data center diesel generator set, characterized in that, The neutral point (P1) of the generator (G) is connected to a common grounding resistor (R) via a vacuum contactor (KM). The vacuum contactor (KM) is controllably switched on and off via a control circuit, which includes... Changeover switch (LW); The remote control contact (P2) is connected to the remote switching side of the changeover switch (LW) in a controllable manner. A local control switch is provided to control the on / off connection of the local switching side of the changeover switch (LW); The coil (KM1) of the vacuum contactor (KM) is connected to the end of the remote control contact (P2) and the local control switch away from the changeover switch (LW). When the remote control contact (P2) or the local control switch is turned on, the coil (KM1) is energized and the vacuum contactor (KM) is closed.

2. The grounding device for a data center diesel generator set according to claim 1, characterized in that, The local control switch includes, A normally closed local trip switch (SA), the first end of which is connected to the local switching side of the transfer switch (LW); A normally open local closing switch (SB) is provided, with its first terminal connected to the second terminal of the local opening switch (SA). The second terminal of the local closing switch (SB) is connected to the coil (KM1). When the local closing switch (SB) is closed, the coil (KM1) is energized, and the vacuum contactor (KM) remains engaged.

3. The grounding device for a data center diesel generator set according to claim 1, characterized in that, It also includes, A current transformer (CT) is connected to the end of the common grounding resistor (R) away from the vacuum contactor (KM); An overcurrent relay (KA) is connected to the secondary side of the current transformer (CT).

4. The grounding device for a data center diesel generator set according to claim 1, characterized in that, It also includes a closing indicator, which includes a closing indicator light (LR) connected to the vacuum contactor (KM), which illuminates when the vacuum contactor (KM) is closed.

5. The grounding device for a data center diesel generator set according to claim 1, characterized in that, It also includes a trip indicator, which includes a trip indicator light (LG) connected to the vacuum contactor (KM) and illuminates when the vacuum contactor (KM) is disconnected.

6. The grounding device for a data center diesel generator set according to claim 1, characterized in that, It also includes a control power supply, the control circuit being connected to the control power supply via a DC power switch (DK1).

7. The grounding device for a data center diesel generator set according to claim 6, characterized in that, The generator (G) is housed in a cabinet and also includes a temperature and humidity controller (WK) for controlling the temperature and humidity inside the cabinet. The temperature and humidity controller (WK) is connected to a temperature and humidity sensor (W1) inside the cabinet and is connected to the control power supply via an AC power switch (DK2).

8. The grounding device for a data center diesel generator set according to claim 1, characterized in that, It also includes a signal transmission unit (K1) connected to the vacuum contactor (KM) and transmitting on / off signals based on the on / off state of the vacuum contactor (KM).

9. The grounding device for a data center diesel generator set according to claim 1, characterized in that, The common grounding resistor (R) comprises several resistor pieces connected in series.

10. The grounding device for a data center diesel generator set according to claim 7, characterized in that, The front side of the cabinet is equipped with a control panel, and the changeover switch (LW) and the local control switch are both located on the control panel.

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