Dummy load switching loading system of double-voltage diesel generating set

Abstract

The utility model relates to a dummy load switching loading system of a double-voltage diesel generating set, which comprises a generating set, a main circuit breaker, a first contactor, a second contactor, a first intermediate relay, a second intermediate relay, an electric heating wire group and a set controller, the six electric heating wires are connected end to end in a delta connection mode after being connected in series pairwise, three-phase lines output by the generator set are connected with the first contactor through the main circuit breaker, three-phase lines of the first contactor are connected to three corners of a triangle of the electric heating wire set respectively, and the second contactor is an N-line switch. Three N lines of the second contactor are respectively connected between two resistance wires of three sides of the triangle of the electric heating wire group, and the unit controller is respectively connected with the first contactor and the second contactor through the first intermediate relay and the second intermediate relay so as to control on-off of the first contactor and the second contactor. According to the system, the dummy load can still operate normally when the generator set outputs different voltages.

Description

Technical Field

[0001] This invention relates to the field of generators, and specifically to a dual-voltage diesel generator set dummy load switching system. Background Technology

[0002] Diesel generator sets are widely used power supply devices that convert diesel fuel into electricity to meet the power needs of various scenarios, including industrial, commercial, and agricultural production. Besides applications in hospitals, data centers, shopping malls, and hotels, they are also widely used in outdoor construction, disaster relief, and military applications. In some situations, diesel generator sets need to respond to the power demands of the load at any time, requiring the unit to be constantly running. However, prolonged operation under low or zero load conditions can lead to carbon buildup in the engine, affecting power generation performance and reducing fuel economy. Therefore, the unit is often connected to the load terminal with an electric heating wire as the load, and its on / off state is controlled by a switch to ensure that the unit can still operate within a high efficiency range under low or zero load conditions, thus ensuring the stability of the load's power supply.

[0003] Generator sets sometimes need to switch between different voltages and frequencies to adapt to the power specifications of different regions. However, the integrated dummy load system cannot be switched arbitrarily. After switching, due to the different voltage, the heating power of the electric heating tube will decrease or increase, deviating from the actual required heating power, and may damage the electric heating tube or even cause the unit to malfunction.

[0004] Although there are independent dummy load cabinets on the market that are suitable for different voltages, they are often large in size, can only be used separately, and are difficult to integrate with diesel generator sets. The integrated diesel generator sets are also large in size, difficult to transport, and costly. Utility Model Content

[0005] The purpose of this invention is to provide a dual-voltage diesel generator set dummy load switching system, which allows the dummy load to operate normally when the generator set outputs different voltages.

[0006] To achieve the above objectives, the technical solution adopted by this utility model is as follows: a dual-voltage diesel generator set dummy load switching loading system, comprising a generator set, a main circuit breaker, a first contactor, a second contactor, a first intermediate relay, a second intermediate relay, an electric heating wire assembly, and a generator set controller. The electric heating wire assembly comprises six electric heating wires, which are connected in series in pairs and then connected end-to-end in a delta configuration. The three-phase output lines of the generator set are connected to the first contactor via the main circuit breaker. The three-phase lines of the first contactor are respectively connected to the three corners of the triangle of the electric heating wire assembly. The second contactor is a neutral (N) switch, and the three N lines of the second contactor are respectively connected between the two resistance wires on the three sides of the triangle of the electric heating wire assembly. The generator set controller is connected to the first contactor and the second contactor via the first intermediate relay and the second intermediate relay, respectively, to control the on / off state of the first contactor and the second contactor through the first intermediate relay and the second intermediate relay.

[0007] Furthermore, the three-phase lines of the voltage acquisition port of the unit controller are respectively connected to the three-phase lines connecting the main circuit breaker and the first contactor.

[0008] Furthermore, the N-line of the voltage acquisition port of the unit controller is connected to the N-line of the generator set.

[0009] Furthermore, the N-line of the generator set is connected to the three N-lines at one end of the second contactor, and the three N-lines at the other end of the second contactor are respectively connected to the two resistance wires on the three sides of the electric heating wire group triangle.

[0010] Furthermore, the generator set is a dual-voltage generator set, capable of outputting two line voltages: 2U and 1.732U.

[0011] Furthermore, the generator set is capable of outputting two line voltages: 440V and 380V.

[0012] Furthermore, the generator set is a dual-voltage diesel generator set.

[0013] Compared with existing technologies, this invention has the following advantages: This invention provides a dual-voltage diesel generator set dummy load switching system. This system can ensure that the heating wires under different line voltages always operate at their rated voltage by switching the connection method of the heating wire group, thus ensuring that the actual heating power required by the generator set for the heating wire group remains unchanged and that the heating wires operate normally. When applied to dual-voltage diesel generator sets with dummy loads, this system reduces the need for selecting and configuring heating wires of different specifications under different voltages, lowering material costs. Furthermore, fewer heating wires reduce the overall space required, making the generator set more adaptable to transportation and the environment. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the dual-voltage diesel generator set dummy load switching loading system according to an embodiment of the present invention;

[0015] Figure 2 This is a schematic diagram of the working state of the electric heating wire assembly when the output line voltage of the generator set is 2U in an embodiment of this utility model;

[0016] Figure 3 This is a schematic diagram of the working state of the electric heating wire assembly when the output line voltage of the generator set is 1.732U in an embodiment of this utility model. Detailed Implementation

[0017] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0018] It should be noted that the following detailed descriptions are exemplary and intended to provide further explanation of this application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0019] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0020] like Figure 1As shown, this embodiment provides a dual-voltage diesel generator set dummy load switching system, including a generator set 1, a main circuit breaker 2, a first contactor 3, a second contactor 4, a first intermediate relay 5, a second intermediate relay 7, an electric heating wire group 8, and a generator set controller 6. The electric heating wire group 8 includes six electric heating wires R1~R6, which are connected in series in pairs and then connected end-to-end in a delta configuration. The three-phase lines U, V, and W output from the generator set 1 are connected to the first contactor 3 via the main circuit breaker 2. The main circuit breaker 20 acts as an output circuit protection device. The three-phase lines U, V, and W of the first contactor 3 are respectively connected to the three corners of the delta configuration of the electric heating wire group 8, and the first contactor 3 controls the on / off connection of the three-phase lines. The second contactor 4 is a neutral (N) line switch. The three neutral (N) lines of the second contactor 4 are respectively connected between the two resistance wires on the three sides of the delta configuration of the electric heating wire group 8, and the second contactor 4 controls the on / off connection of the three neutral (N) lines. The unit controller 6 is connected to the first contactor 3 and the second contactor 4 via the first intermediate relay 5 and the second intermediate relay 7, respectively, to control the on / off state of the first contactor 3 and the second contactor 4 through the first intermediate relay 5 and the second intermediate relay 7. Contactors 3 and 4 are used to switch between different heating wire circuit connections. Intermediate relays 5 and 7 receive control signals from the unit controller 6 to control the engagement and disengagement of the contactors, thereby controlling the operation of the heating wires in different circuits.

[0021] The three-phase lines of the voltage acquisition port 9 of the generator controller 6 are connected to the three-phase lines U, V, and W connecting the main circuit breaker 2 and the first contactor 3, respectively, i.e., connected to the three-phase lines between the main circuit breaker 2 and the first contactor 3. The neutral (N) line of the voltage acquisition port 9 of the generator controller 6 is connected to the neutral (N) line of the generator set 1. The voltage sampling port can acquire the generated voltage. When the generator set starts successfully and generates electricity normally, the generator controller 6 will determine the voltage type based on the voltage, thereby determining which relay coil needs to be activated, and then controlling the contactor to activate and control the dummy load, so as to achieve the normal operation of the dummy load.

[0022] The N line of generator set 1 is connected to the three N lines at one end of the second contactor 4, and the three N lines at the other end of the second contactor 4 are respectively connected to the two resistance wires on each side of the triangle of electric heating wire group 8.

[0023] like Figure 2-3 As shown, in this embodiment, heating wires R1 and R2 are connected in series, R3 and R4 are connected in series, and R5 and R6 are connected in series. The six heating wires are connected in pairs to form three sides, and then connected end-to-end to form a triangle. The three phase lines U, V, and W of the first contactor 3 are connected between R1 and R6, R2 and R3, and R4 and R5, respectively. The three neutral (N) lines of the second contactor 4 are connected between R1 and R2, R3 and R4, and R5 and R6, respectively.

[0024] In this system, the generator set is a dual-voltage generator set, capable of outputting two line voltages: 2U and 1.732U.

[0025] In this way, the unit controller 6 can control the first intermediate relay 5 and the second intermediate relay 7 according to the collected voltage and the set PLC program. It should be noted that the implementation of the PLC program to control the on and off of the first intermediate relay 5 and the second intermediate relay 7 according to the collected voltage is a well-known technology in the art, and therefore will not be described in detail here.

[0026] like Figure 2 As shown, in actual operation, when the generator set generates electricity normally and the output voltage is 2U, the unit controller 6 determines whether the dummy load system needs to be started based on the load status. If the unit controller 6 determines that the dummy load system needs to be started, the unit controller 6 outputs a signal based on the monitored voltage 2U to make the first intermediate relay 5 energize and control the first contactor 3 to energize. At this time, every two electric heating wires connected in series work at voltage 2U, and each electric heating wire works at the rated voltage U. The electric heating wire group operates normally.

[0027] like Figure 3 As shown, when the output voltage is 1.732U, the unit controller 6 outputs a signal based on the monitored voltage of 1.732U to simultaneously activate the first intermediate relay 5 and the second intermediate relay 7, and controls the first contactor 3 and the second contactor 4 to activate. At this time, each heating wire operates at the rated voltage U, and the heating wire group operates normally.

[0028] In this embodiment, the system operates on a dual-voltage diesel generator set, which can operate at both 440V and 380V. The system achieves normal operation under different voltages by switching the connection of the electric heating wires. When the diesel generator set outputs 440V, the first contactor 3 is switched on and the second contactor 4 is switched off, forming a delta connection. In the delta connection, two electric heating wires with a rated voltage of 220V are connected in series between phases U and V. According to the characteristics of a series circuit, the voltage drop across each heating wire is 220V, meaning the voltage applied to a single heating wire is the rated voltage. At this time, the heating wires can operate normally. The connection between phases U and W, and between phases V and W, follows the same principle, resulting in a balanced three-phase load. When the diesel generator set is switched to 380V, the line voltage is 380V and the phase voltage is 220V. At this time, a wire is drawn from the midpoint of the two series-connected electric heating wires and connected to the N line. At this time, the voltage on each electric heating wire is still 220V, and the electric heating wire is still operating at the rated voltage. The connection method for the other two phases is similar, and the three-phase load is balanced.

[0029] The above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model in any other way. Any person skilled in the art may make changes or modifications to the disclosed technical content to create equivalent embodiments. However, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of this utility model without departing from its scope of protection shall still fall within the protection scope of this utility model.

Claims

1. A dual voltage diesel generator set dummy load switching loading system, characterized by, The generator set, the main circuit breaker, the first contactor, the second contactor, the first intermediate relay, the second intermediate relay, the electric heating wire group and the unit controller, the electric heating wire group includes six electric heating wires, the six electric heating wires are connected in series two by two and connected in a triangle connection mode, the three-phase line output by the generator set is connected to the first contactor through the main circuit breaker, the three-phase line of the first contactor is connected to the three corners of the electric heating wire group triangle respectively, the second contactor is an N line switch, the three N lines of the second contactor are connected between the two electric resistance wires of the three edges of the electric heating wire group triangle respectively, and the unit controller is connected to the first contactor and the second contactor through the first intermediate relay and the second intermediate relay respectively, so as to control the on-off of the first contactor and the second contactor through the first intermediate relay and the second intermediate relay respectively.

2. A dual voltage diesel generator set pseudo load switching system according to claim 1, characterized in that, The three-phase line of the voltage acquisition port of the unit controller is connected with the three-phase line connected with the main circuit breaker and the first contactor.

3. A dual voltage diesel generator set pseudo load switching system according to claim 2, wherein, The N line of the voltage acquisition port of the unit controller is connected with the N line of the generator set.

4. A dual voltage diesel generator set pseudo load switching system according to claim 1, wherein, The N line of the generator set is connected with the three N lines at one end of the second contactor, and the three N lines at the other end of the second contactor are connected between the two electric resistance wires of the three edges of the electric heating wire group triangle respectively.

5. A dual voltage diesel generator set pseudo load switching system according to claim 1 wherein, The generator set is a dual-voltage generator set and can output two line voltages of 2U and 1.732U.

6. A dual voltage diesel generator set pseudo load switching system according to claim 5 wherein, The generator set can output two line voltages of 440V and 380V.

7. A dual voltage diesel generator set pseudo load switching system according to claim 5 wherein, The generator set is a dual-voltage diesel generator set.

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