Underground explosion-proof static SVG power unit control system with temperature detection function

Abstract

The utility model relates to an underground explosion-proof static SVG (static var generator) power unit control system with a temperature detection function, which comprises a power unit, a redundant temperature sampling circuit, an analog-to-digital conversion circuit, a water chilling unit, a lower computer controller and a liquid crystal display screen. Two signal output ends of the redundant temperature sampling circuit are connected with respective analog-to-digital conversion circuits through transmission lines, signal output ends of the analog-to-digital conversion circuits are connected to a lower computer controller through transmission lines, and an output end and a control interface of the lower computer controller are respectively connected with a liquid crystal display and a water chilling unit. The current control end of the lower computer controller is connected to the current adjusting end of the underground explosion-proof static var generator power unit through an optical fiber. Temperature detection of the power unit of the underground reactive generator is achieved, the requirement for the field use environment is low, the stability of equipment is good, and stable operation of the equipment is guaranteed.

Description

Technical Field

[0001] The utility model relates to the technical field of temperature detection, in particular to a control system for an underground explosion-proof static SVG power unit with temperature detection. Background Technique

[0002] The power quality of the underground power grid includes the monitoring of the operation of tunneling equipment, large-scale hoists, fans, and high-voltage frequency converters in coal mines. Due to the influence of the underground environment, the internal environment temperature of the underground static var generator is relatively high, and the ambient temperature has a crucial impact on the operation of the equipment. When the temperature inside the cavity of the underground static var generator is too high and the system continues to operate in a large-capacity compensation state, when the hardware of the power unit of the system exceeds the tolerable limit temperature, the control system will trip. Therefore, in this case, the temperature detection and control device for the power unit of the underground explosion-proof device is particularly important. Summary of the Invention

[0003] The utility model provides a control system for an underground explosion-proof static SVG power unit with temperature detection, which has strong versatility for general underground explosion-proof control systems, has a simple structure, is convenient for use and maintenance, has a compact overall structure and a small volume, has low requirements for the on-site use environment, has good equipment stability, can achieve a good temperature detection effect in the underground explosion-proof control device, and assists the underground explosion-proof static var generator to operate stably.

[0004] In order to achieve the above object, the utility model is realized by adopting the following technical solutions:

[0005] A control system for an underground explosion-proof static SVG power unit with temperature detection includes a power unit, a redundant temperature detection circuit, a water cooling unit, a lower computer controller, and a liquid crystal display screen. The redundant temperature detection circuit includes a redundant temperature sampling circuit and an analog-to-digital conversion circuit. The redundant temperature sampling circuit is arranged at the three-phase current output end of the power unit of the underground explosion-proof static var generator. The two signal output ends of the redundant temperature sampling circuit are connected to their respective analog-to-digital conversion circuits through transmission lines. The signal output end of the analog-to-digital conversion circuit is connected to the lower computer controller through an optical fiber. The output end of the lower computer controller is connected to the liquid crystal display. The current control end of the lower computer controller is connected to the current adjustment end of the power unit of the underground explosion-proof static var generator through an optical fiber. The lower computer controller is connected to the water cooling unit through a control interface.

[0006] Furthermore, the redundant temperature sampling circuit includes a redundant temperature sensor, a redundant controller, and a redundant power supply. The redundant power supply supplies power to the redundant controller and the redundant temperature sensor. The redundant temperature sensor is connected to the analog input interface of the redundant controller.

[0007] Further, the analog-to-digital conversion circuit includes a digital-to-analog conversion processor, a digital tube, a triode, a resistor, and a pull-up resistor. The digital quantity read signal terminal of the digital-to-analog conversion processor is connected to the digital tube. The IO interface of the digital-to-analog conversion processor is connected to the pull-up resistor. In the circuit formed by the digital-to-analog conversion processor and the pull-up resistor, two of the pull-up resistors are connected to one end of the digital-to-analog conversion processor and then respectively connected in series with corresponding resistors and triodes. The collectors of the different triodes are connected in parallel and then connected to the power supply. The emitters of the different triodes are connected to the digital quantity input interface of the lower computer controller.

[0008] Further, the lower computer controller includes a CPU chip, a pulse width modulation (PWM) module, an analog quantity module, a digital quantity module, a power supply module, and a switch quantity module. The switch quantity module is connected to an external door body control button. The digital quantity input interface of the CPU chip is connected to the digital quantity output terminal of the digital conversion circuit. The output terminal of the pulse width modulation (PWM) module is connected to the current regulation terminal of the power unit of the underground explosion-proof static var generator.

[0009] Further, it further includes an SVG power supply controller, an SVG controller, an external interface, and an external CT / PT transformer. The power supply module of the lower computer controller is respectively connected to the SVG power supply controller and the SVG controller through transmission lines. The digital quantity module of the lower computer controller is connected to the external interface through a transmission line. The analog quantity module of the lower computer controller is connected to the external CT / PT transformer through a transmission line.

[0010] Further, the water-cooled unit includes an internal water-cooled unit and an external water-cooled unit.

[0011] Further, the redundant temperature sampling circuit is respectively arranged at the uppermost layer position of phase A, the middle position of phase B, and the bottommost position of phase C at the three-phase current output end of the power unit inverter system of the underground explosion-proof static var generator.

[0012] Compared with the prior art, the beneficial effects of the present utility model are as follows:

[0013] 1) Through the independent control design of the redundant temperature detection circuit and the original system, the acquisition and control of the power unit temperature and the temperature control of other parts of the original system adopt completely independent system controls. The operation control parts between the two do not interfere with each other. The temperature acquisition and control device adopted by the power unit is separated from the high-voltage electrical device of the system, which maximally ensures the safety of the system. The power unit structures of the three phases are the same, and they can be mutually replaced with each other to maximally realize the versatility of the equipment. It can be applied to the design of the environmental temperature control system device of general underground explosion-proof devices;

[0014] 2) By adopting the configuration of a redundant temperature detection circuit, when one output line fails, it switches to the other detection circuit to collect and transmit the temperature value, ensuring the stability and reliability of the system;

[0015] 3) This device meets the compensation standard of the general technical conditions for underground power grids. The system has strong compatibility, a compact unit structure, excellent performance, strong adaptability, is convenient for use and maintenance, has almost no requirements for on-site maintenance personnel, etc. The system topology structure is simple and easy to use, and is applicable to many underground environments. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic structural diagram of the present utility model.

[0017] Figure 2 It is a schematic structural diagram of the digital-to-analog conversion circuit of the present utility model. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0018] The following further describes the specific embodiments of the present utility model with reference to the drawings:

[0019] See Figure 1 , which is a schematic structural diagram of the present utility model. A control system for an underground explosion-proof static SVG power unit with temperature detection of the present utility model includes a power unit, a redundant temperature detection circuit, a water cooling unit, a lower computer controller, an SVG power supply controller, an SVG controller, an external interface, an external CT / PT transformer, and a liquid crystal display screen; the redundant temperature sampling circuits are respectively arranged at the uppermost layer position of phase A, the middle position of phase B, and the bottommost position of phase C at the three-phase current output end of the power unit inverter system of the underground explosion-proof static var generator. The redundant temperature detection circuit includes a redundant temperature sampling circuit and an analog-to-digital conversion circuit; the two signal output ends of the redundant temperature sampling circuit are connected to their respective analog-to-digital conversion circuits through transmission lines, the signal output end of the analog-to-digital conversion circuit is connected to the lower computer controller through an optical fiber, the output end of the lower computer controller is connected to the liquid crystal display, the current control end of the lower computer controller is connected to the current adjustment end of the power unit of the underground explosion-proof static var generator through an optical fiber, and the lower computer controller is connected to the internal water cooling unit and the external water cooling unit through a control interface.

[0020] The redundant temperature sampling circuit includes a redundant temperature sensor, a redundant controller, and a redundant power supply. The redundant power supply supplies power to the redundant controller and the redundant temperature sensor, and the redundant temperature sensor is connected to the analog input interface of the redundant controller.

[0021] The analog-to-digital conversion circuit includes a digital-to-analog conversion processor, a digital tube, a triode Q1, a triode Q2, a resistor R8, a resistor R9, and a 4.7K pull-up resistor. The digital-to-analog conversion processor uses an AT89C51 chip. The digital quantity read signal terminal of the digital-to-analog conversion processor is connected to the digital tube. The IO interfaces P0.0 to P0.5 of the digital-to-analog conversion processor are respectively connected to the pull-up resistor. The P0.4 of the digital-to-analog conversion processor is in series with the resistor R9 and the triode Q2. The P0.5 interface of the digital-to-analog conversion processor is in series with the resistor R8 and the triode Q1. The collectors of the triode Q1 and the triode Q2 are connected in parallel and then connected to the power supply. The emitters of the triode Q1 and the triode Q2 are connected to the digital quantity input interface of the lower computer controller.

[0022] The lower computer controller includes a CPU chip, a pulse width modulation PWM module, an analog quantity module, a digital quantity module, a power supply module, and a switch quantity module. The switch quantity module is connected to the external door body control button. The power supply module is connected to the SVG power supply controller and the SVG controller. The digital quantity input interface of the CPU chip is connected to the digital quantity output end of the digital conversion circuit. The output end of the pulse width modulation PWM module is connected to the current regulation end of the power unit of the underground explosion-proof static var generator.

[0023] Working principle: The topological structures of the A, B, and C phase power units of the power unit inverter system of the underground explosion-proof static var generator are the same. The topological structures of the temperature detection devices of the A, B, and C phase inverter power units described in the system are the same, but their installation positions in the system are different. The position layout is such that the temperature detection of phase A is installed at the top layer, the temperature detection of phase B is arranged in the middle, and the temperature detection device of phase C is installed at the bottom. Other structural modes can also be adopted. The temperature of the power unit is connected to the analog-to-digital conversion circuit of the system using the topological structure of the transmission line, and the wiring terminal uses the optical isolation method to ensure the safety of the system.

[0024] The temperature sampling circuit collects the temperature of the power unit, transmits it to the analog-to-digital conversion circuit through the transmission line, and then transmits it to the lower computer controller through the optical fiber. After being calculated by the lower computer controller, the pulse width modulation PWM module adjusts the output current. If the ambient temperature is higher than the maximum value allowed by the equipment, the output current will rapidly decrease. The single-phase power units adopt a series connection mode step by step, and the temperature acquisition devices are respectively installed at the upper, middle, and lower positions of the entire cavity according to the structural layout.

[0025] The temperature sampling circuit detects the value of the ambient temperature. To ensure the stability of the system, a redundant temperature sampling circuit is adopted. The two groups of sampling circuits operate in a forced alternating sampling mode when a fault occurs. The value is transmitted to the analog-to-digital conversion device through a transmission line, and then analog-to-digital conversion is performed to convert the analog quantity into a digital quantity. Then, the digital quantity is transmitted to the lower computer controller through an optical fiber. After calculation by the lower computer controller, the output current is controlled. When the temperature is too high and higher than the value allowed by the system, the output current of the system is quickly reduced. When the system temperature returns to the allowed value, the output current is restored to the normal value.

[0026] The structural design of the present utility model complies with the General Technical Standard for Underground Power Grid Compensation Devices GB / T 3836.1-2021. The temperature sampling circuit is installed separately and will not affect the topological structure of the traditional control device. The redundant temperature detection circuit is small in size, easy to install, and the whole machine is assembled with a general cascaded topological structure. The equipment is easy to repair. The temperature acquisition and control device adopts an independent installation mode, which is more conducive to the installation of the equipment and the debugging of the system, making the installation and position allocation of the whole machine more reasonable, effectively utilizing the underground space, and making the equipment easier to be effectively used.

[0027] The above embodiments are implemented on the premise of the technical solution of the present utility model, and the detailed implementation methods and specific operation processes are given. However, the protection scope of the present utility model is not limited to the above embodiments. The methods used in the above embodiments are conventional methods unless otherwise specified.

Claims

1. An underground explosion-proof static SVG power unit control system with temperature detection, characterized in that: It includes a power unit, a redundant temperature detection circuit, a water cooling unit, a lower computer controller and a liquid crystal display screen. The redundant temperature detection circuit includes a redundant temperature sampling circuit and an analog-to-digital conversion circuit. The redundant temperature sampling circuit is arranged at the three-phase current output end of the underground explosion-proof static reactive generator power unit. The two signal output ends of the redundant temperature sampling circuit are connected to the respective analog-to-digital conversion circuits through transmission lines. The signal output end of the analog-to-digital conversion circuit is connected to the lower computer controller through an optical fiber. The output end of the lower computer controller is connected to the liquid crystal display. The current control end of the lower computer controller is connected to the current regulating end of the underground explosion-proof static reactive generator power unit through an optical fiber. The lower computer controller is connected to the water cooling unit through a control interface.

2. The underground explosion-proof static SVG power unit control system with temperature detection according to claim 1 is characterized in that: The redundant temperature sampling circuit includes a redundant temperature sensor, a redundant controller and a redundant power supply. The redundant power supply supplies power to the redundant controller and the redundant temperature sensor. The redundant temperature sensor is connected to an analog input interface of the redundant controller.

3. The underground explosion-proof static SVG power unit control system with temperature detection according to claim 1 is characterized in that: The analog-to-digital conversion circuit includes a digital-to-analog conversion processor, a digital tube, a transistor, a resistor and a pull-up resistor. The digital quantity reading signal end of the digital-to-analog conversion processor is connected to the digital tube, and the IO interface of the digital-to-analog conversion processor is connected to the pull-up resistor. In the circuit formed by the digital-to-analog conversion processor and the pull-up resistor, two pull-up resistors are connected to one end of the digital-to-analog conversion processor and then connected in series with corresponding resistors and transistors respectively. The collectors of different transistors are connected in parallel and then connected to a power supply, and the emitters of different transistors are connected to the digital quantity input interface of the lower computer controller.

4. The underground explosion-proof static SVG power unit control system with temperature detection according to claim 1 is characterized in that: The lower computer controller includes a CPU chip, a pulse width modulation PWM module, an analog module, a digital module, a power supply module and a switch module. The switch module is connected to an external door control button, the digital input interface of the CPU chip is connected to the digital output end of the digital conversion circuit, and the output end of the pulse width modulation PWM module is connected to the current regulation end of the power unit of the underground explosion-proof static reactive generator.

5. The underground explosion-proof static SVG power unit control system with temperature detection according to claim 4 is characterized in that: It also includes an SVG power supply controller, an SVG controller, an external interface, and an external CT / PT transformer. The power supply module of the lower machine controller is connected to the SVG power supply controller and the SVG controller respectively through transmission lines, the digital module of the lower machine controller is connected to the external interface through a transmission line, and the analog module of the lower machine controller is connected to the external CT / PT transformer through a transmission line.

6. The underground explosion-proof static SVG power unit control system with temperature detection according to claim 1, characterized in that: The water cooling unit comprises an internal water cooling unit and an external water cooling unit.

7. The underground explosion-proof static SVG power unit control system with temperature detection according to claim 1, characterized in that: The redundant temperature sampling circuits are respectively arranged at the top position of phase A, the center position of phase B and the bottom position of phase C at the three-phase current output end of the power unit inverter system of the underground explosion-proof static VAR generator.

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