A diesel generating control circuit for an electrical switchboard

Abstract

The utility model relates to a power distribution cabinet technical field discloses a diesel power generation control circuit of power distribution cabinet, including dual power conversion module, multichannel distribution output module, measurement module, protection module, control module, overload protection and alarm module, its characterized in that: dual power conversion module adopts isolated PC level dual power automatic transfer switch ATS, and the input side is connected commonly used power supply and diesel power supply spare power respectively through independent fuse group, is used for the quick automatic switching between two power, and the output side is connected multichannel distribution output module and measurement module respectively. In the utility model, through isolated PC level ATS in dual power conversion module combines the fuse group of both sides, realizes the automatic switching and access protection of commonly used power supply and diesel spare power, avoids the power supply interruption caused by single power failure, and can provide the stable power supply after switching for multichannel distribution output module, thereby satisfies the power demand of different load power among each measurement.

Description

Technical Field

[0001] This utility model relates to the field of power distribution cabinet technology, and in particular to a diesel generator control circuit for a power distribution cabinet. Background Technology

[0002] In industrial production, large-scale construction, and critical infrastructure, a continuous and stable power supply is a core prerequisite for ensuring the normal operation of the system. Diesel generators, as commonly used emergency backup power sources, need to be quickly switched on and put into operation when the mains power is interrupted to avoid production stoppages, equipment damage, or safety risks caused by power outages. Therefore, it is necessary to develop a diesel generator control circuit for a distribution cabinet.

[0003] However, in the circuit design of existing technology, the diesel generator control circuit of traditional distribution cabinets generally suffers from slow power switching response, making it difficult to meet the high requirements of critical loads for power supply continuity, and it is also difficult to adapt to the power distribution needs of different power loads. Utility Model Content

[0004] To overcome the above shortcomings, this utility model provides a diesel generator control circuit for a power distribution cabinet, aiming to improve the problems of slow power switching response and difficulty in adapting to the power distribution needs of different power loads in the prior art.

[0005] To achieve the above objectives, this utility model provides the following technical solution: a diesel generator control circuit for a power distribution cabinet, comprising a dual power conversion module, a multi-channel power distribution output module, a measurement module, a protection module, a control module, and an overload protection and alarm module. The dual power conversion module adopts an isolated PC-level dual power automatic transfer switch (ATS). The input side is connected to the main power supply and the diesel generator backup power supply via independent fuse groups for rapid automatic switching between the two power supplies. The output side is connected to the multi-channel power distribution output module and the measurement module. The multi-channel power distribution output module includes four independent outgoing circuits, each circuit being connected in series. The circuit is equipped with current transformers, thermal relays, and molded case circuit breakers. Different specifications of molded case circuit breakers and cables can be used to adapt to loads of different power ratings, and each circuit is independently controlled. The dual power conversion module is electrically connected to the multi-channel power distribution output module, the measurement module, and the protection module. The multi-channel power distribution output module is electrically connected to the protection module, the measurement module, and the overload protection and alarm module. The measurement module is signal-connected to the control module. The protection module is signal-connected to the control module. The control module is signal-connected to the overload protection and alarm module. The overload protection and alarm module is electrically connected to the multi-channel power distribution output module.

[0006] Preferably, the dual power automatic transfer switch (ATS) of the dual power conversion module is used to automatically switch between the main power supply and the diesel generator backup power supply to ensure power supply continuity. The phase and neutral wires of the main power supply of the dual power automatic transfer switch (ATS) are connected to the main power supply terminal of the ATS after passing through the first fuse group, and the phase and neutral wires of the backup power supply on the backup power supply side of the dual power automatic transfer switch (ATS) are connected to the backup power supply terminal of the ATS after passing through the second fuse group.

[0007] Preferably, the protection module includes a molded case circuit breaker and a surge protection unit. The surge protection unit includes a backup protector (SCB) and a surge protector (SPD). The backup protector (SCB) and the surge protector (SPD) are connected in series and then in parallel to the output of a dual power automatic transfer switch (ATS) between a three-phase four-wire power supply. One end of the backup protector (SCB) is connected to the output of the dual power automatic transfer switch (ATS), and the other end of the surge protector (SPD) is grounded.

[0008] Preferably, the measurement module consists of a current transformer, a thermal relay, a multi-function meter (PM), and a reserved current telemetry unit. The secondary side output of the current transformer is connected to the thermal relay, which is used for overload protection of the circuit. The output lines of the thermal relay are connected to the current input terminals of the multi-function meter (PM). The voltage input terminals of the multi-function meter are connected to the three-phase four-wire power supply output of the dual-power automatic transfer switch (ATS). The secondary side output of the current transformer is connected to the reserved current telemetry unit. The output lines of the reserved current telemetry unit are connected to the current input terminals of the multi-function meter (PM). The voltage input terminals of the multi-function meter (PM) are connected to the three-phase four-wire power supply. The multi-function meter (PM) is equipped with a fuse for overcurrent protection.

[0009] Preferably, the overload protection and alarm module consists of a fuse, a thermal relay, an intermediate relay, and a terminal block. The fuse is connected in series in the phase line L1. The contacts of the thermal relay are connected in series with the coils of the corresponding intermediate relays and then connected to the neutral line. The contacts of the intermediate relays are connected to the terminal block XT. The terminal block XT is used to transmit the overload alarm signal to an external system.

[0010] Preferably, the control module includes three sets of fire-fighting emergency protection units and terminal block assemblies. The terminal block assemblies include three sets of terminal blocks XT, XT1, and XT3. The lines of terminal block XT1 are respectively connected to the secondary side output lines of the current transformer. Terminal block XT1 is used to connect to multiple terminals of the multi-function instrument PM through different serial number terminals. Terminal block XT1 is also connected to the protective ground wire PE and has a current telemetry interface.

[0011] Preferably, each fire-fighting emergency trip protection unit consists of a molded case circuit breaker, an intermediate relay, a fuse, and a terminal block. One end of the fuse is connected to the power supply 2L1, and the other end is connected to the normally open contact of the intermediate relay. The other end of the normally open contact of the intermediate relay is connected to the shunt trip unit of the molded case circuit breaker. The coil ends of the intermediate relay are connected to the DC24V control signal output by the fire protection system. The molded case circuit breaker is equipped with normally closed auxiliary contacts and normally open auxiliary contacts. The normally closed auxiliary contacts and normally open auxiliary contacts are respectively connected to the corresponding terminals of the terminal block to feed back the on / off status signal of the molded case circuit breaker QF2 to the external monitoring system.

[0012] Preferably, in the multi-channel power distribution output module, the power from the generator vehicle is connected to the dual-power automatic transfer switch (ATS) via a line. The dual-power automatic transfer switch (ATS) is an isolated PC-level dual-power automatic transfer and self-reset device. The output terminal of the dual-power automatic transfer switch (ATS) is connected in parallel with a branch formed by a series-connected backup protector (SCB) and surge protector (SPD). The other end of the surge protector (SPD) is grounded. The output terminal of the dual-power automatic transfer switch (ATS) is connected in series with a main circuit transformer and then connected to a multi-function meter (PM). Four outgoing circuits are led out from the output terminal of the dual-power automatic transfer switch (ATS). Each circuit is connected in series with a corresponding branch transformer, a thermal relay, and a molded case circuit breaker (MCCB), and then connected to different power metering rooms via corresponding cables. The MCBs QF2, QF3, and QF4 are respectively connected to intermediate relays KA2, KA3, and KA4.

[0013] This utility model has the following beneficial effects: 1. In this utility model, by combining the isolated PC-level ATS in the dual power conversion module with the fuse groups on both sides, the automatic switching and access protection between the main power supply and the diesel backup power supply is realized, avoiding power outages caused by single power supply failures. It can also provide a stable power supply after switching to multiple power distribution output modules, thereby meeting the power demand of different loads in each metering room. This circuit design can build a comprehensive safety barrier for the entire power distribution system, significantly improving the stability and safety of the diesel generator control in the distribution cabinet.

[0014] 2. In this utility model, the surge protection unit in the protection module, together with the molded case circuit breakers and thermal relays of each circuit, forms a two-level protection for the main circuit and the branch circuits. This can not only intercept abnormal risks such as surge overvoltage and short circuit current, but also provide precise protection against single circuit overload. At the same time, the cooperation between the current transformer and the multi-functional instrument enables real-time current monitoring, which can provide early warning of abnormal loads and reduce the probability of equipment damage and circuit failure.

[0015] 3. In this utility model, the fire-fighting emergency tripping protection unit in the control module can support remote emergency tripping, and in conjunction with the intermediate relay and terminal block assembly, it can realize remote control and status feedback of circuit on / off, meet the needs of fire emergency and intelligent management. By reserving the current telemetry unit and terminal block interface, remote monitoring, data transmission and other functions can be easily expanded, adapting to function upgrades in different scenarios and improving overall operation and maintenance efficiency. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the overall circuit structure of a diesel generator control circuit for a power distribution cabinet proposed in this utility model. Figure 2 This is a schematic diagram of the dual power conversion module circuit structure of the diesel generator control circuit of the power distribution cabinet proposed in this utility model. Figure 3 This utility model provides a schematic diagram of the multi-channel power distribution output module circuit structure of a diesel generator control circuit for a power distribution cabinet. Figure 4 A schematic diagram of the control module circuit structure of a diesel generator control circuit for a power distribution cabinet proposed in this utility model; Figure 5 This utility model provides a schematic diagram of the measurement module circuit structure for a diesel generator control circuit in a power distribution cabinet. Figure 6 This is a schematic diagram of the terminal block interface structure of a diesel generator control circuit for a power distribution cabinet according to the present invention. Figure 7 This utility model presents a schematic diagram of the overload protection and alarm module circuit of a diesel generator control circuit for a power distribution cabinet. Detailed Implementation

[0017] The technical solutions of the embodiments 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, and 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 protection scope of this utility model.

[0018] Reference Figures 1-7This utility model provides an embodiment of a diesel generator control circuit for a power distribution cabinet, comprising a dual power conversion module, a multi-channel power output module, a measurement module, a protection module, a control module, and an overload protection and alarm module. The dual power conversion module employs an isolated PC-grade dual power automatic transfer switch (ATS). The input side is connected to the main power supply and the diesel generator backup power supply via independent fuse groups for rapid automatic switching between the two power supplies. The output side is connected to the multi-channel power output module and the measurement module. The multi-channel power output module includes four independent outgoing circuits, each circuit connected in series. It can be connected to current transformers, thermal relays and molded case circuit breakers, and can be adapted to loads of different power by using molded case circuit breakers of different specifications and cables. Each circuit is independently controlled. The dual power conversion module is electrically connected to the multi-channel power distribution output module, measurement module and protection module respectively. The multi-channel power distribution output module is electrically connected to the protection module, measurement module and overload protection and alarm module respectively. The measurement module is connected to the control module for signal, the protection module is connected to the control module for signal, the control module is connected to the overload protection and alarm module for signal, and the overload protection and alarm module is electrically connected to the multi-channel power distribution output module. Specifically, by connecting the main power supply and the backup diesel generator provided by the generator vehicle to the input side of the dual power conversion module, the output side can transmit power signals to the measurement module for parameter monitoring. By connecting a multi-channel power distribution output module, a stable, switched power supply can be provided to meet the high requirements of critical loads for power continuity. After the multi-channel power distribution output module obtains power from the dual power conversion module, it distributes the power to various loads through multiple independent power distribution lines, adapting to the power distribution needs of different power loads. Each distribution line first passes through a current transformer, thermal relay, and molded case circuit breaker to ensure power distribution safety. Simultaneously, each line is connected to a measurement module to measure parameters such as current in each circuit, and some lines are also connected to overload protection and alarm modules to achieve overload monitoring and alarm for specific circuits. By connecting the surge protector (SPD) and backup protector (SCB) in parallel at the output of the dual power conversion module, surge overvoltages in the power system can be protected. The measurement module acquires current signals from each power distribution circuit via current transformers and voltage signals via the output of the dual power conversion module. These signals are transmitted to a multi-functional instrument for processing and display, enabling real-time monitoring of the entire power distribution system's operating parameters. The measurement module can also feed back measurement data to the control module, providing a basis for its decision-making. The protection module feeds back its operational status information to the control module. The control module receives operating parameter data from the measurement module and operational status information from the protection module, performs comprehensive analysis and judgment, and controls the power switching action of the dual power conversion module according to preset logic and rules. Simultaneously, the control module can control the overload protection and alarm module, providing overload alarms and controlling related circuits. A thermal relay in the overload protection and alarm module is connected in series in part of the power distribution lines of the multi-channel power output module to monitor current conditions in real time. When an overload is detected, the thermal relay activates, triggering an intermediate relay, which then issues an alarm signal through the control module. Furthermore, the intermediate relay can disconnect related power distribution circuits according to control module commands to protect equipment and lines.

[0019] Reference Figure 2 The dual power conversion module's automatic transfer switch (ATS) is used to automatically switch between the main power supply and the diesel generator backup power supply to ensure power supply continuity. The phase and neutral wires of the main power supply of the ATS are connected to the main power supply terminal of the ATS after passing through the first fuse group. The phase and neutral wires of the backup power supply on the backup power supply side of the ATS are connected to the backup power supply terminal of the ATS after passing through the second fuse group.

[0020] Specifically, the dual power conversion module, through the automatic transfer switch (ATS), enables automatic switching between the primary power supply and the diesel generator backup power supply. The ATS is equipped with a first fuse group (1FU1, 1FU2, 1FU3) on both the primary and backup power supply sides, and a second fuse group (2FU1, 2FU2, 2FU3). These fuse groups preliminarily intercept and disconnect short-circuit and overload fault currents in both power lines before the power supply is connected to the ATS, preventing fault currents from directly entering the ATS and damaging the switch, thus effectively protecting the core components of the ATS. Simultaneously, these two fuse groups prevent the spread of power supply faults caused by abnormal power line conditions, ensuring the safety and stability of both power supply connections, further enhancing the reliability of the dual power conversion module, and ensuring the ATS operates normally when switching is required. This continuously and stably supplies power to the subsequent multiple power distribution output modules, ultimately providing dual protection for the power supply continuity of the entire distribution cabinet's diesel generator control circuit.

[0021] Reference Figures 1-7 The protection module includes a molded case circuit breaker and a surge protection unit. The surge protection unit includes a backup protector (SCB) and a surge protector (SPD). The SCB and SPD are connected in series and then in parallel to the three-phase four-wire power supply at the output of the automatic transfer switch (ATS). One end of the SCB is connected to the output of the ATS, and the other end of the SPD is grounded. The measurement module consists of a current transformer, a thermal relay, a multi-function meter (PM), and a reserved current telemetry unit. The secondary side output of the current transformer is connected to the thermal relay, which is used for overload protection of the circuit. The output lines of the thermal relay are connected to the current input terminals of the multi-function meter (PM), and the voltage input terminals of the multi-function meter are connected to... The three-phase four-wire power supply of the dual-power automatic transfer switch (ATS) is connected accordingly. The secondary side output of the current transformer is connected to the reserved current telemetry unit. The output lines of the reserved current telemetry unit are connected to the current input terminals of the multi-function instrument PM. The voltage input terminals of the multi-function instrument PM are connected to the three-phase four-wire power supply. The multi-function instrument PM is equipped with a fuse for overcurrent protection. The overload protection and alarm module consists of a fuse, a thermal relay, an intermediate relay, and a terminal block. The fuse is connected in series in the phase line L1. The contacts of the thermal relay are connected in series with the coils of the corresponding intermediate relays and then connected to the neutral line. The contacts of the intermediate relays are connected to the terminal block XT. The terminal block XT is used to transmit the overload alarm signal to the external system. Specifically, surge protectors (SPDs) limit overvoltages on electrical lines or equipment, absorb surge energy, and protect equipment from transient overvoltages such as lightning strikes and switching overvoltages. Backup protectors (SCBs) disconnect the circuit promptly when the SPD malfunctions, preventing larger electrical accidents and ensuring the safe operation of the entire lightning protection system. The series connection of the SPD and SPB enhances the safety and stability of the electrical system. When a surge overvoltage occurs at the output of the automatic transfer switch (ATS), the SPD quickly conducts to release the overvoltage to ground, providing protection. The SPB, as a dedicated protection element for the SPD, is positioned close to the power supply side and can quickly disconnect the circuit when the SPD experiences a short circuit, preventing continuous short-circuit current damage to the power supply or causing larger malfunctions. The combination of these two components forms a complete surge protection system. The surge protector (SPD) absorbs abnormal voltages such as surge overvoltages and lightning-induced voltages from the power grid, preventing high-voltage surges to subsequent distribution circuits and load equipment. The backup protector (SCB) promptly disconnects the circuit when the SPD experiences a short-circuit fault, preventing the fault from escalating and protecting the SPD itself. Molded case circuit breakers (MCCBs) can quickly disconnect short-circuit and overload faults in each distribution line, ensuring the safety of the lines and loads. In the measurement module, the current transformer converts the large current in the main circuit into a smaller current. This is initially monitored for overload via a thermal relay, and further expanded to include remote monitoring via a reserved current telemetry unit. All these components are then connected to a multi-function meter (PM). Combined with the power signal from the output of the automatic transfer switch (ATS) acquired at the PM's voltage input, accurate monitoring of system current, voltage, and other parameters is achieved. The fuse connected to the PM also prevents overcurrent damage to the measurement circuit, ensuring stable measurement functionality. In the overload protection and alarm module, a fuse connected in series with phase line L1 first provides short-circuit protection for the module's own circuitry. Then, through the series connection of the normally open contact of the thermal relay and the coil of the intermediate relay, the intermediate relay is triggered when an overload is detected. The alarm signal is then transmitted to the external system via terminal block XT, providing timely early warning of overload faults. Through the coordinated operation of these modules, the safe, stable, and reliable operation of the diesel generator control circuit in the distribution cabinet can be comprehensively ensured.

[0022] Reference Figures 1-7The control module includes three sets of fire-fighting emergency trip protection units and terminal block assemblies. The terminal block assemblies include three sets of terminal blocks XT, XT1, and XT3. The wiring of terminal block XT1 is connected to the secondary side output of the current transformer. Terminal block XT1 uses different numbered terminals to connect to multiple terminals of the multi-function instrument PM. Terminal block XT1 is also connected to the protective ground wire PE and has a current telemetry interface. Each fire-fighting emergency trip protection unit consists of a molded case circuit breaker, an intermediate relay, a fuse, and terminal blocks. One end of the fuse is connected to power supply 2L1, and the other end is connected to the normally open contact of the intermediate relay. The other end of the normally open contact of the intermediate relay is connected to the shunt trip unit of the molded case circuit breaker. The coil ends of the intermediate relay are connected to the DC24V control signal output from the fire protection system. The molded case circuit breaker is equipped with normally closed auxiliary contacts and normally open auxiliary contacts, which are respectively wired to the corresponding terminals of the terminal blocks. The connection is used to feed back the on / off status signal of the molded case circuit breaker QF2 to the external monitoring system; the multi-channel power distribution output module is connected to the dual power automatic transfer switch ATS through the power of the generator car. The dual power automatic transfer switch ATS is an isolated PC-level dual power automatic transfer and self-reset device. The output terminal of the dual power automatic transfer switch ATS is connected in parallel with the branch formed by the series-connected backup protector SCB and surge protector SPD. The other end of the surge protector SPD is grounded. The output terminal of the dual power automatic transfer switch ATS is connected in series with the main circuit transformer and then connected to the multi-function meter PM. The output terminal of the dual power automatic transfer switch ATS leads out four outgoing circuits. Each circuit is connected in series with the corresponding branch transformer, thermal relay and molded case circuit breaker, and then connected to the metering room of different power through the corresponding cables. The molded case circuit breakers QF2, QF3 and QF4 are connected to the intermediate relays KA2, KA3 and KA4 respectively. Specifically, the terminal block assembly uses XT1 to achieve precise connection between the secondary side signal of the current transformer and the multi-function instrument PM, while also accommodating the needs of protective grounding and current telemetry expansion. This ensures the reliability of current signal transmission and provides interface support for flexible expansion of system monitoring functions. Terminal blocks XT and XT3 further optimize the internal wiring connections of the module and its connection to external devices, improving circuit standardization and maintainability. In the fire-fighting emergency trip protection unit, the control circuit is first protected against overcurrent by a fuse. Then, the intermediate relay can be driven by the fire-fighting DC24V emergency trip control signal to activate its normally open contact, thereby triggering the shunt trip unit of the molded case circuit breaker to achieve emergency tripping. The fire-fighting system outputs a DC24V control signal, connected to the coil ends of the intermediate relay, corresponding to line numbers 205 and 207. When the fire-fighting system issues a control signal, the intermediate relay coil is energized, its normally open contact closes, triggering the shunt trip unit to quickly disconnect the power supply to the corresponding circuit, meeting the mandatory power-off requirements under fire conditions. The normally closed and normally open auxiliary contacts of the molded case circuit breaker (MCCB) can feed back their on / off status to an external monitoring system via terminal blocks. When the MCCB is normally closed, the normally closed contacts are closed and the normally open contacts are open. When the MCCB trips, the normally closed contacts open and the normally open contacts close. These contacts are connected to terminal blocks XT3 via lines corresponding to line numbers 209, 211, and 213, feeding back the MCCB's status signal to the external monitoring system. This achieves trip signal return, allowing monitoring personnel to understand the MCCB's operating status. This enables status monitoring and remote visualization of fire-fighting emergency tripping actions, ensuring the effective execution and status traceability of fire control commands. There are three groups of MCCBs (QF2, QF3, and QF4), each with the same connection method and control logic, corresponding to different power supply circuits. All can be controlled by the fire protection system to achieve emergency tripping and feed back their status signals. Through reasonable component connections and functional configuration, the control module not only realizes the transfer and expansion of current signals but also constructs a reliable fire-fighting emergency tripping protection mechanism, while ensuring the monitorability of the system's operating status. In the multi-channel power distribution output module, the generator truck's power supply is first connected to an isolated PC-level dual-power automatic transfer switch (ATS) via a line. The isolated PC-level dual-power automatic transfer switch (ATS) ensures the reliability of power supply access and the automation of switching. Furthermore, the isolation design enhances circuit safety. The output of the dual-power automatic transfer switch (ATS) is connected in parallel with a branch formed by a series-connected backup protector (SCB) and surge protector (SPD). This allows the SPD to effectively absorb surge overvoltages, protecting subsequent circuits and equipment from impact, while the SCB can promptly disconnect the circuit in the event of a SPD failure, preventing fault propagation. A multi-function instrument is connected in series with the output of the isolated PC-level dual-power automatic transfer switch (ATS) via a main current transformer, enabling real-time monitoring of the total output current parameters and providing data support for system operating status assessment.The four outgoing circuits are then connected in series with corresponding branch current transformers, thermal relays, and molded case circuit breakers. The branch current transformers monitor the branch current of each outgoing line, allowing for monitoring of the specific power consumption in each metering room. The thermal relays provide overload protection, while the molded case circuit breakers provide short-circuit and overcurrent protection. Connected in series in each distribution line of the multi-circuit power distribution module, the molded case circuit breakers promptly disconnect the circuit in case of overload or short-circuit faults, protecting the load and line safety. This multi-layered protection ensures the safety of power distribution in each circuit, and each circuit is connected to metering rooms with different power ratings via corresponding cables, meeting diverse power consumption needs. This rational connection design achieves safe power conversion, stable distribution, accurate monitoring, and reliable protection, providing comprehensive protection for power consumption in metering rooms with different power ratings.

[0023] Working Principle: In operation, this circuit uses a dual-power transfer module as its core, employing an isolated PC-level ATS to automatically switch between the primary power supply and the diesel generator backup power supply. Before each power supply is connected, two sets of fuses provide initial protection, ensuring the safe operation of the dual-power automatic transfer switch (ATS). The output of the ATS connects to a multi-function instrument via a main current transformer, and is also connected in parallel with a series-connected backup protector (SCB) and surge protector (SPD). This provides both total output current monitoring and surge voltage absorption via the SPD, while the backup protector (SCB) prevents fault propagation. The four outgoing circuits from the ATS output each pass through a branch current transformer, a thermal relay, and a molded case circuit breaker. The system forms a two-level current monitoring and multi-protection system for the main circuit and branch circuits. Molded case circuit breakers QF2 to QF4, in conjunction with intermediate relays KA2 to KA4, enable remote control and status feedback. Power is then distributed to different power metering rooms via corresponding cables. The measurement module, through the cooperation of current transformers, thermal relays, and multi-function instruments, can collect current and voltage parameters in real time and feed them back to the control module. The control module can receive monitoring data and protection signals from the measurement and protection modules, and achieve circuit disconnection in emergencies through the fire-fighting emergency trip protection unit. Simultaneously, it uses terminal block assemblies to achieve signal transfer and linkage with external systems. The overload protection and alarm module triggers intermediate relays via thermal relays, transmitting alarm signals to external systems via terminal blocks.

[0024] Through the coordinated work of various modules, not only is the continuity of power supply and the safety of power distribution ensured, but also the accurate monitoring, remote control and fault early warning of system operation status are realized, meeting the reliable power supply requirements in diesel power generation scenarios.

[0025] Finally, it should be noted that the above are merely preferred embodiments of the present utility model and are not intended to limit the present utility model. Although the present utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A diesel generator control circuit for a power distribution cabinet, comprising a dual power conversion module, a multi-channel power output module, a measurement module, a protection module, a control module, and an overload protection and alarm module, characterized in that: The dual power conversion module adopts an isolated PC-grade dual power automatic transfer switch (ATS). The input side is connected to the main power supply and the diesel generator backup power supply via independent fuse groups for rapid automatic switching between the two power sources. The output side is connected to a multi-channel power distribution output module and a measurement module. The multi-channel power distribution output module contains four independent outgoing circuits, each circuit consisting of a corresponding current transformer, thermal relay, and molded case circuit breaker connected in series. Different specifications of molded case circuit breakers and cables can be used to adapt to loads of different power ratings, and each circuit is independently controlled. The dual power conversion module is electrically connected to the multi-channel power distribution output module, the measurement module, and the protection module. The multi-channel power distribution output module is electrically connected to the protection module, the measurement module, and the overload protection and alarm module. The measurement module is signal-connected to the control module, the protection module is signal-connected to the control module, the control module is signal-connected to the overload protection and alarm module, and the overload protection and alarm module is electrically connected to the multi-channel power distribution output module.

2. The diesel generator control circuit of the distribution cabinet according to claim 1, characterized in that: The dual power conversion module's automatic transfer switch (ATS) is used to automatically switch between the main power supply and the diesel generator backup power supply to ensure power supply continuity. The phase and neutral wires of the main power supply of the ATS are connected to the main power supply terminal of the ATS via a first fuse group, and the phase and neutral wires of the backup power supply on the backup power supply side of the ATS are connected to the backup power supply terminal of the ATS via a second fuse group.

3. The diesel generator control circuit for a distribution cabinet according to claim 1, characterized in that: The protection module includes a molded case circuit breaker and a surge protection unit. The surge protection unit includes a backup protector (SCB) and a surge protector (SPD). The backup protector (SCB) and the surge protector (SPD) are connected in series and then in parallel to the output of a dual power automatic transfer switch (ATS) for a three-phase four-wire power supply. One end of the backup protector (SCB) is connected to the output of the dual power automatic transfer switch (ATS), and the other end of the surge protector (SPD) is grounded.

4. The diesel generator control circuit of the distribution cabinet according to claim 1, characterized in that: The measurement module consists of a current transformer, a thermal relay, a multi-function meter (PM), and a reserved current telemetry unit. The secondary side output of the current transformer is connected to the thermal relay, which is used for overload protection of the circuit. The output lines of the thermal relay are connected to the current input terminals of the multi-function meter (PM). The voltage input terminals of the multi-function meter are connected to the three-phase four-wire power supply output of the dual-power automatic transfer switch (ATS). The secondary side output of the current transformer is connected to the reserved current telemetry unit. The output lines of the reserved current telemetry unit are connected to the current input terminals of the multi-function meter (PM). The voltage input terminals of the multi-function meter (PM) are connected to the three-phase four-wire power supply. The multi-function meter (PM) is equipped with a fuse for overcurrent protection.

5. The diesel generator control circuit for a distribution cabinet according to claim 1, characterized in that: The overload protection and alarm module consists of a fuse, a thermal relay, an intermediate relay, and a terminal block. The fuse is connected in series in the phase line L1. The contacts of the thermal relay are connected in series with the coils of the corresponding intermediate relays and then connected to the neutral line. The contacts of the intermediate relays are connected to the terminal block XT. The terminal block XT is used to transmit the overload alarm signal to an external system.

6. The diesel generator control circuit of the distribution cabinet according to claim 1, characterized in that: The control module includes three sets of fire-fighting emergency protection units and terminal block assemblies. The terminal block assemblies include three sets of terminal blocks XT, XT1, and XT3. The lines of terminal block XT1 are respectively connected to the secondary side output lines of the current transformer. Terminal block XT1 is used to connect to multiple terminals of the multi-function instrument PM through different serial number terminals. Terminal block XT1 is also connected to the protective ground wire PE and has a current telemetry interface.

7. The diesel generator control circuit for a distribution cabinet according to claim 6, characterized in that: Each fire-fighting emergency trip protection unit consists of a molded case circuit breaker, an intermediate relay, a fuse, and a terminal block. One end of the fuse is connected to the power supply 2L1, and the other end is connected to the normally open contact of the intermediate relay. The other end of the normally open contact of the intermediate relay is connected to the shunt trip unit of the molded case circuit breaker. The coil ends of the intermediate relay are connected to the DC24V control signal output by the fire protection system. The molded case circuit breaker is equipped with normally closed auxiliary contacts and normally open auxiliary contacts. The normally closed auxiliary contacts and normally open auxiliary contacts are respectively connected to the corresponding terminals of the terminal block to feed back the on / off status signal of the molded case circuit breaker QF2 to the external monitoring system.

8. The diesel generator control circuit of the distribution cabinet according to claim 1, characterized in that: The multi-channel power distribution output module is connected to the dual-power automatic transfer switch (ATS) via a power source from a generator truck. The ATS is an isolated PC-level dual-power automatic transfer and reset device. The output terminal of the ATS is connected in parallel with a branch formed by a series-connected backup protector (SCB) and surge protector (SPD). The other end of the SPD is grounded. The output terminal of the ATS is connected in series with a main circuit transformer and then connected to a multi-function meter (PM). Four outgoing circuits are led out from the output terminal of the ATS. Each circuit is connected in series with a corresponding branch transformer, a thermal relay, and a molded case circuit breaker (MCCB), and then connected to different power metering rooms via corresponding cables. The MCCBs QF2, QF3, and QF4 are respectively connected to intermediate relays KA2, KA3, and KA4.

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