Inverter power supply suitable for underground environment and power supply method

Abstract

The invention provides an inverter power supply suitable for an underground environment and a power supply method, the inverter power supply suitable for the underground environment comprises a main control unit, a power driving unit and a power transformer, the main control unit comprises an FPGA main control unit and at least one following driving unit; the power driving unit is connected with the FPGA main control unit through the following driving unit and is connected with the power transformer, and a primary circuit of a single-phase bridge type inverter circuit in the power driving unit is made of a SiC switch tube. The invention provides an inverter power supply capable of converting low-voltage direct current of a battery into high-voltage alternating current capable of being used by a motor in a high-temperature environment and a use method thereof, so as to realize the opening and closing operation of a caliper arm of a logging instrument. Meanwhile, the working state of the high-temperature lithium battery is accurately monitored in real time, and the operation safety is ensured.

Description

Technical Field

[0001] The present invention relates to the field of oil development, in particular to the technical field related to oil well logging instruments, and in particular to an inverter power supply and a power supply method suitable for an underground environment. Background Art

[0002] When the storage logging instrument performs downhole data measurement, the logging instrument is generally powered by a high-temperature lithium battery with an operating temperature of 175℃ to 200℃. When the storage logging instrument is working, some instruments need to open and retract the arm to ensure good logging quality. However, the power supply in the logging instrument in the prior art cannot meet the above temperature requirements. Therefore, a high-temperature-resistant and high-power inverter circuit is required to convert the low-voltage DC obtained from the battery into a high-voltage AC that can be used by the motor, thereby realizing the opening and retraction of the borehole arm.

[0003] In addition, high-temperature lithium batteries are dangerous goods, especially since their operating temperature is basically close to the melting point of metallic lithium. Therefore, more accurate monitoring measures are needed to ensure that high-temperature lithium batteries can be used to the maximum extent under safe conditions. Summary of the invention

[0004] The embodiments of the present invention provide an inverter power supply and power supply method suitable for downhole environments, and provide an inverter power supply and a method of using the inverter power supply that can convert the low-voltage DC of a battery into a high-voltage AC that can be used by a motor in a high-temperature environment, so as to realize the opening and closing operations of the wellbore arm of a logging instrument; at the same time, the working status of the high-temperature lithium battery is monitored in real time and accurately to ensure operation safety.

[0005] On the one hand, an embodiment of the present invention provides an inverter power supply suitable for an underground environment, comprising:

[0006] It includes: main control unit, power drive unit and power transformer, among which:

[0007] The main control unit includes an FPGA main control unit and at least one follower drive unit;

[0008] The power drive unit is connected to the FPGA main control unit through the follower drive unit and is connected to the power transformer, and the primary circuit of the single-phase bridge inverter circuit in the power drive unit is made of SiC switch tube.

[0009] In some embodiments of the present invention, the inverter power supply suitable for underground environment further includes: an undervoltage control circuit and a current limiting control circuit, wherein:

[0010] The undervoltage control circuit and the current limiting control circuit are both connected to the FPGA main control unit;

[0011] The undervoltage control circuit is used to monitor the voltage of the inverter power supply;

[0012] The current limiting control circuit is used to monitor the current of the inverter power supply.

[0013] In some embodiments of the present invention, the inverter power supply suitable for underground environment further includes: a DC voltage monitoring circuit, a DC current monitoring circuit and a digital-to-analog conversion circuit, wherein:

[0014] The undervoltage control circuit and the current limiting control circuit are connected to the power driving unit via the DC voltage monitoring circuit, the DC current monitoring circuit and / or the digital-to-analog conversion circuit.

[0015] In some embodiments of the present invention, the inverter power supply suitable for underground environment further includes: an AC voltage monitoring circuit, an AC current monitoring circuit, a signal voltage dividing circuit and a rectifier circuit, wherein:

[0016] The DC voltage monitoring circuit, the DC current monitoring circuit and the digital-to-analog conversion circuit are connected to the power transformer via the AC voltage monitoring circuit, the AC current monitoring circuit, the signal voltage divider circuit and / or the rectifier circuit.

[0017] In some embodiments of the present invention, the inverter power supply suitable for underground environment further includes: a 485 bus communication unit for transmitting the battery usage result of the inverter power supply to the surface system; and

[0018] The step-up ratio of the power transformer is 1:2.

[0019] On the other hand, an embodiment of the present invention provides a power supply method for an inverter power supply suitable for an underground environment, the method comprising:

[0020] In response to the power supply instruction, a plurality of control signals are generated by the main control unit, wherein the voltage signals in each control signal have the same frequency and a phase difference of 180°;

[0021] By performing preset closing and opening operations on a plurality of switches in the power drive unit, and generating a sinusoidal wave voltage according to the plurality of groups of control signals;

[0022] The sinusoidal wave voltage is amplified by a power transformer, and the amplified sinusoidal wave voltage is sent to the instrument motor.

[0023] In some embodiments of the present invention, performing preset closing and opening operations on a plurality of switches in the power drive unit and generating a sinusoidal voltage according to the plurality of control signals includes:

[0024] Closing or opening two switches of the plurality of switches at a preset frequency to generate an AC voltage;

[0025] The AC voltage is subjected to capacitor filtering to generate the sinusoidal wave voltage.

[0026] In some embodiments of the present invention, the power supply method applicable to the underground environment further includes:

[0027] The voltage and output current of the battery are monitored by the FPGA main control unit in the main control unit.

[0028] In some embodiments of the present invention, the power supply method applicable to the underground environment further includes:

[0029] The battery usage power, power supply current, accumulated usage time and power supply voltage are stored in the processor through the FPGA main control unit to generate a battery usage result.

[0030] In some embodiments of the present invention, the power supply method applicable to the underground environment further includes:

[0031] The battery usage result is sent to the ground system via the 485 bus communication unit.

[0032] From the above description, it can be seen that an embodiment of the present invention provides an inverter power supply and a power supply method suitable for an underground environment. The inverter power supply suitable for an underground environment includes: a main control unit, a power drive unit and a power transformer; the main control unit includes an FPGA main control unit and at least one follower drive unit; the power drive unit is connected to the FPGA main control unit through the follower drive unit, and is connected to the power transformer, and the primary circuit of the single-phase bridge inverter circuit in the power drive unit is made of SiC switching tube.

[0033] The power supply method suitable for an underground environment includes: in response to a power supply instruction, a main control unit generates multiple groups of control signals, the voltage signals in each group of control signals have the same frequency and a phase difference of 180°; a plurality of switches in a power drive unit are closed and opened in a preset manner, and a sinusoidal wave voltage is generated according to the multiple groups of control signals; the sinusoidal wave voltage is amplified by a power transformer, and the amplified sinusoidal wave voltage is sent to an instrument motor.

[0034] The inverter power supply suitable for underground environment provided by the present invention can ensure normal operation under 175°C environment, and under this temperature environment, the conversion efficiency of the high-temperature lithium battery power supply is not less than 85%. Secondly, the power supply method suitable for underground environment provided by the present invention can monitor the voltage and output current of the high-temperature lithium battery in real time, and monitor the power of the high-temperature lithium battery in real time. Finally, the remaining power result of the high-temperature lithium battery can be stored and uploaded to the inside of the instrument. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0036] Figure 1 Schematic diagram of the circuit structure of an inverter power supply suitable for an underground environment in an embodiment of the present invention;

[0037] Figure 2 Schematic diagram of a power supply method suitable for an underground environment provided in an embodiment of the present invention Figure 1 ;

[0038] Figure 3 It is a flowchart of step 200 in the power supply method applicable to the underground environment provided in an embodiment of the present invention;

[0039] Figure 4 Schematic diagram of a power supply method suitable for an underground environment provided in an embodiment of the present invention Figure 2 ;

[0040] Figure 5 Schematic diagram of a power supply method suitable for an underground environment provided in an embodiment of the present invention Figure 3 ;

[0041] Figure 6 A schematic diagram of the structure of a main control unit provided in an embodiment of the present invention;

[0042] Figure 7 Schematic diagram of a power supply method suitable for an underground environment provided in an embodiment of the present invention Figure 4 ;

[0043] Figure 8 It is a flow chart of a power supply method suitable for an underground environment in a specific application example of the present invention;

[0044] Fig. 9 It is a schematic diagram of the structure of an electronic device in an embodiment of the present invention. DETAILED DESCRIPTION

[0045] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0046] In the prior art, the patent application with application number 201410847822.3 relates to a high-temperature power supply for oil well logging, which includes an input filter circuit, a PWM main controller circuit, a flyback transformer circuit, a power switch tube circuit, an output rectifier filter circuit and a feedback circuit. The flyback transformer circuit is respectively connected to the input filter circuit, the switch power tube circuit, the PWM main controller circuit and the output rectifier filter circuit. The switch power tube circuit is also connected to the PWM main controller circuit. The feedback circuit is respectively connected to the output rectifier filter circuit and the PWM main controller circuit. The high-temperature power supply for oil well logging can apply the switch power supply to the high-temperature environment of industrial fields such as oil and steel, providing a fundamental guarantee for measuring instruments. It can not only solve the stability and reliability problems of the high-temperature field environment in the industrial field, but also open up a new and broad space for the application of the switch power supply. This high-temperature power supply embodies its advantages of small size, high efficiency, high cost performance and high reliability. The operating temperature range of this power supply is generally between -40℃ and +85℃, which cannot meet the high-temperature applications in some specific industrial fields such as petroleum, steel and other industries, that is, it cannot be used in a high-temperature environment of +85℃ to +125℃.

[0047] Embodiment 1:

[0048] Based on this, the embodiment of the present invention provides a specific implementation of an inverter power supply suitable for an underground environment, see Figure 1 , main control unit, power drive unit and power transformer, among which:

[0049] The main control unit includes an FPGA main control unit and at least one follower drive unit;

[0050] The power drive unit is connected to the FPGA main control unit through the follower drive unit and is connected to the power transformer, and the primary circuit of the single-phase bridge inverter circuit in the power drive unit is made of SiC switch tube.

[0051] FPGA (Field-Programmable Gate Array) is an integrated circuit chip with flexible and programmable logic and circuit functions. Unlike traditional ASIC (Application-Specific Integrated Circuit), FPGA can be reprogrammed after the design is completed, so that it can adapt to different application requirements.

[0052] In an embodiment of the present invention, the FPGA is composed of a programmable logic unit (PLU) and a programmable interconnect resource (PIR). The programmable logic unit is a group of basic logic units, such as gates, triggers, and multiplexers, which can be programmed to implement the required logic functions. The programmable interconnect resource is a set of programmable wires and crosspoints that can connect the logic units together according to design requirements. FPGA programming usually uses a hardware description language (HDL) to describe logic functions and circuit connections. Commonly used HDLs include VHDL (VHSIC Hardware Description Language) and Verilog. By writing HDL code, the designer can define the signal transmission and logic operations between logic units.

[0053] One of the advantages of FPGA is flexibility. Due to its reprogrammable nature, FPGA can be modified and optimized after the design is completed without redesigning and manufacturing new chips. This flexibility makes FPGA play an important role in rapid prototyping, algorithm verification, and product customization. In addition, FPGA also has highly parallel processing capabilities. The logic units in FPGA can perform multiple operations at the same time, thereby achieving efficient data processing and calculation. This makes FPGA advantageous in applications that require high performance and low latency, such as digital signal processing, image processing, and network communications. However, one of the disadvantages of FPGA is its relatively high power consumption and cost. Compared with ASIC, FPGA usually requires more power consumption to achieve the same logical function, and its manufacturing cost is also higher. Therefore, in applications with strict requirements on power consumption and cost, ASIC may be more suitable. In general, FPGA is a flexible and programmable integrated circuit chip with highly parallel processing capabilities. It plays an important role in rapid prototyping, algorithm verification, and product customization, but it also has problems with high power consumption and cost.

[0054] It should be noted that the FPGA main control unit uses an FPGA chip that can operate in an environment of 175°C as the core processor.

[0055] In addition, the power drive unit uses high-temperature resistant SiC switching tubes to build an H-bridge circuit to provide power for the normal operation of the high-temperature motor.

[0056] The power drive unit selects SiC switching tube as the core power chip, which is a power device that can work normally in an environment of 175°C. At the same time, it has high voltage resistance and high-speed switching characteristics to obtain higher working efficiency and less electromagnetic interference.

[0057] A power transformer, also known as an electric transformer, is an electrical device used to change AC voltage and current. Through the principle of electromagnetic induction, it converts the electrical energy at the input end into the electrical energy at the output end, achieving voltage rise and fall and current conversion.

[0058] A power transformer consists of two or more coils wound around the same core, one of which is called the primary coil and the other or other coils are called the secondary coils. The primary coil is connected to the power supply and inputs the electrical energy into the transformer, while the secondary coil is connected to the load and outputs the electrical energy from the transformer. By adjusting the ratio of the number of turns of the primary coil and the secondary coil, the input voltage to the output voltage can be transformed. Its working principle is based on the law of electromagnetic induction. When an alternating current is passed through the primary coil, the alternating magnetic field generated passes through the secondary coil, thereby inducing an electromotive force in the secondary coil. According to the law of electromagnetic induction, the electromotive force induced in the secondary coil is proportional to the current in the primary coil. Therefore, by controlling the ratio of the number of turns of the primary and secondary coils, the input and output voltages can be transformed. Power transformers have the following important features:

[0059] Transformation ratio: A transformer can transform input voltage into different output voltages. The transformation ratio is the ratio of the number of turns of the primary coil to the number of turns of the secondary coil, which determines the voltage conversion ratio of the transformer.

[0060] Power Transmission: Power transformers can realize the conversion of input power to output power. The converted power is equal to the input voltage multiplied by the input current, and also equal to the output voltage multiplied by the output current.

[0061] Efficiency: The efficiency of a power transformer is the ratio of output power to input power. Efficiency is usually higher under high load conditions, but may drop under low load conditions.

[0062] Insulation performance: Power transformers usually have good insulation performance, which can isolate the input and output circuits to ensure safe and reliable operation.

[0063] From the above description, it can be seen that an embodiment of the present invention provides an inverter power supply suitable for an underground environment, including: a main control unit, a power drive unit and a power transformer; the main control unit includes an FPGA main control unit and at least one follower drive unit; the power drive unit is connected to the FPGA main control unit through the follower drive unit, and is connected to the power transformer, and the primary circuit of the single-phase bridge inverter circuit in the power drive unit is made of SiC switching tube.

[0064] The embodiment of the present invention provides an inverter power supply that can convert the low-voltage DC of the battery into a high-voltage AC that can be used by the motor in a high-temperature environment to realize the opening and closing operations of the wellbore arm; at the same time, it can accurately monitor the working status of the high-temperature lithium battery in real time to ensure safe use.

[0065] Embodiment 2:

[0066] In some embodiments of the present invention, see Figure 1 , the inverter power supply suitable for underground environment also includes: undervoltage control circuit and current limiting control circuit

[0067] The undervoltage control circuit and the current limiting control circuit are both connected to the FPGA main control unit;

[0068] The undervoltage control circuit is used to monitor the voltage of the inverter power supply;

[0069] The current limiting control circuit is used to monitor the current of the inverter power supply.

[0070] Specifically, an undervoltage control circuit is a circuit used to monitor the voltage of a circuit or device and trigger corresponding protection measures when the voltage is lower than a set threshold. It is used to protect the circuit or device from damage or failure caused by too low voltage.

[0071] In an embodiment of the present invention, the undervoltage control circuit is composed of a comparator, a reference voltage source and some external components. The reference voltage source provides a set threshold voltage, and the comparator compares the input voltage with the reference voltage. When the input voltage is lower than the set threshold, the output of the comparator triggers the corresponding protection mechanism, such as disconnecting the power supply, cutting off the load, triggering an alarm, etc.

[0072] In the undervoltage control circuit, the selection of the reference voltage source is very critical. Preferably, the reference voltage source can be implemented by components such as a resistor divider, a voltage regulator diode, and a voltage regulator. By adjusting the parameters of these components, the required undervoltage protection threshold can be set.

[0073] A current limiting control circuit is a circuit used to monitor the current of a circuit or device and trigger corresponding protective measures when the current exceeds a set threshold. It is used to protect circuits or devices from damage or failure caused by current overload. The current limiting control circuit consists of a current sensor, a comparator, and some external components. The current sensor is used to detect the current in a circuit or device and convert it into a voltage signal. The comparator compares the current signal with the set threshold. When the current exceeds the set threshold, the output of the comparator triggers the corresponding protection mechanism, such as disconnecting the power supply, cutting off the load, triggering an alarm, etc.

[0074] In the current limiting control circuit, the selection of current sensor is very important. Commonly used current sensors include resistive current sensor, Hall effect sensor, current transformer, etc. Different sensors have different characteristics and application ranges, and need to be selected according to specific requirements.

[0075] In some embodiments of the present invention, see Figure 1 , inverter power supplies suitable for underground environments also include:

[0076] A DC voltage monitoring circuit, a DC current monitoring circuit and a digital-to-analog conversion circuit, wherein:

[0077] The undervoltage control circuit and the current limiting control circuit are connected to the power driving unit via the DC voltage monitoring circuit, the DC current monitoring circuit and / or the digital-to-analog conversion circuit.

[0078] The DC voltage monitoring circuit is a circuit used to monitor the voltage in a DC power supply or circuit and provide a corresponding voltage signal. It consists of a voltage sensor, a comparator, and some external components. The voltage sensor is used to detect the voltage in a DC power supply or circuit and convert it into a voltage signal. The comparator compares the voltage signal with the set threshold. When the voltage exceeds or falls below the set threshold, the output of the comparator triggers the corresponding protection mechanism, such as disconnecting the power supply, cutting off the load, triggering an alarm, etc.

[0079] The DC current monitoring circuit is used to monitor the current in a DC power supply or circuit and provide a corresponding current signal. It consists of a current sensor, a comparator, and some external components. The current sensor is used to detect the current in a DC power supply or circuit and convert it into a voltage signal. The comparator compares the current signal with the set threshold. When the current exceeds or falls below the set threshold, the output of the comparator triggers the corresponding protection mechanism, such as disconnecting the power supply, cutting off the load, triggering an alarm, etc.

[0080] The digital-to-analog converter (ADC) is a circuit that converts analog signals into digital signals. It consists of a sample and hold circuit, an analog-to-digital converter, and some external components. The sample and hold circuit is used to obtain the instantaneous value of the analog signal and hold it in a fixed capacitor or voltage memory. The analog-to-digital converter converts the held analog signal into a digital signal, usually using a successive approximation (SAR) or integral (Sigma-Delta) converter. The converted digital signal can be processed and analyzed by a microcontroller, digital signal processor, or other digital circuit.

[0081] In some embodiments of the present invention, see Figure 1 The inverter power supply suitable for underground environment also includes: AC voltage monitoring circuit, AC current monitoring circuit, signal voltage dividing circuit and rectification circuit, among which:

[0082] The DC voltage monitoring circuit, the DC current monitoring circuit and the digital-to-analog conversion circuit are connected to the power transformer via the AC voltage monitoring circuit, the AC current monitoring circuit, the signal voltage divider circuit and / or the rectifier circuit. Specifically:

[0083] The AC voltage monitoring circuit is a circuit used to monitor the voltage in the AC power supply or circuit and provide a corresponding voltage signal. It consists of a voltage sensor, a comparator and some external components. The voltage sensor is used to detect the voltage in the AC power supply or circuit and convert it into a voltage signal. The comparator compares the voltage signal with the set threshold. When the voltage exceeds or falls below the set threshold, the output of the comparator triggers the corresponding protection mechanism, such as disconnecting the power supply, cutting off the load, triggering an alarm, etc.

[0084] The AC current monitoring circuit is a circuit used to monitor the current in the AC power supply or circuit and provide a corresponding current signal. It consists of a current sensor, a comparator and some external components. The current sensor is used to detect the current in the AC power supply or circuit and convert it into a voltage signal. The comparator compares the current signal with the set threshold. When the current exceeds or falls below the set threshold, the output of the comparator triggers the corresponding protection mechanism, such as disconnecting the power supply, cutting off the load, triggering an alarm, etc.

[0085] The signal voltage divider circuit is used to reduce the amplitude of the input signal to a level suitable for subsequent circuit processing. It consists of a resistor divider, a comparator, and some external components. The resistor divider reduces the amplitude of the input signal according to the required voltage divider ratio, and the comparator compares the divided signal with the set threshold. Based on the comparison result, the output of the comparator can trigger the corresponding logic control or protection measures.

[0086] Rectifier circuit is a circuit used to convert AC signal into DC signal. It consists of a diode bridge rectifier and some external components. The diode bridge rectifier can convert the negative half cycle of AC signal into positive half cycle, thus obtaining an output signal close to DC. Rectifier circuit is often used for AC power conversion and DC circuit power supply.

[0087] In some embodiments of the present invention, see Figure 1 , inverter power supplies suitable for underground environments also include:

[0088] A 485 bus communication unit, used to transmit the battery usage result of the inverter power supply to the ground system; and

[0089] The step-up ratio of the power transformer is 1:2.

[0090] 485 bus communication is a serial communication protocol used to achieve data transmission between devices in applications such as industrial automation and remote monitoring.

[0091] 485 bus communication uses differential signals to transmit data. On the transmission line, two wires are used to transmit the positive and negative logic levels respectively, and the binary data is represented by the level difference. This differential transmission method can effectively resist external electromagnetic interference and improve the reliability of data transmission. In 485 bus communication, each device has a unique address to indicate the data sending and receiving objects. A master device can communicate with multiple slave devices at the same time, and realize data transmission by sending instructions and receiving responses. The communication rate can select different baud rates. A higher baud rate can increase the data transmission speed, but it also increases the noise interference of the communication line.

[0092] 485 bus communication supports multiple master-slave structures. The master device can actively send instructions to the slave device, or receive data actively reported by the slave device. This flexible communication method makes 485 bus communication suitable for complex industrial automation scenarios, such as monitoring systems, building automation, environmental monitoring, etc.

[0093] Preferably, the power transformer uses a 1:2 step-up transformer to step up the pulsating AC signal of about 100V to 220VAC@50Hz AC to power the 220AC single-phase AC motor used in the high-temperature storage logging instrument. Since the transformer is relatively large, it is installed externally on the instrument frame. It can work normally at temperatures below 200°C.

[0094] Embodiment three:

[0095] The embodiment of the present invention also provides a power supply method suitable for underground environment, which is applied to an inverter power supply suitable for underground environment. Figure 2 , the method specifically includes the following contents:

[0096] Step 100: In response to the power supply instruction, a plurality of control signals are generated by the main control unit, wherein the voltage signals in each control signal have the same frequency and a phase difference of 180°;

[0097] Specifically, see Figure 1 , using an FPGA chip that can work in an environment of 175℃ as the core processor, the voltages V1 and V2 output from ports 1 and 2 of the FPGA main control unit are both 50Hz and square wave pulses with a phase difference of 180°; the voltages V3 and V4 output from ports 3 and 4 are also square wave pulses with a frequency of 50Hz and a phase difference of 180°. Among them, the amplitude V1=V2=V3=V4, V1 and V4 have the same phase, V2 and V3 have the same phase, and the generated control signal is sent after the follower drive unit and controls the power drive unit.

[0098] Step 200: performing preset closing and opening operations on a plurality of switches in the power drive unit, and generating a sinusoidal wave voltage according to the plurality of control signals;

[0099] SiC switch tube is a new type of power semiconductor device, which uses silicon carbide (SiC) as the main material. Compared with traditional silicon (Si) power devices, SiC switch tube has higher operating temperature, lower conduction and switching losses, higher switching speed and higher voltage resistance. SiC switch tube has the following main features:

[0100] High temperature characteristics: SiC material has high thermal conductivity and low temperature coefficient, which enables SiC switch tubes to work in high temperature environments. In contrast, the operating temperature of traditional silicon power devices is usually limited.

[0101] Low conduction and switching losses: Due to the wide bandgap of SiC materials, SiC switches have lower conduction and switching losses. This makes SiC switches more efficient and smaller in high-frequency and high-power applications.

[0102] High switching speed: SiC switch tubes have very fast switching speeds, which can achieve higher switching frequencies. This is very important for some applications that require high-speed switching, such as power conversion, electric vehicles, and solar inverters.

[0103] High voltage resistance: SiC switch tubes have higher voltage resistance and can withstand higher voltages. This makes SiC switch tubes more reliable and stable in high voltage applications.

[0104] Step 300: Amplify the sinusoidal wave voltage through a power transformer, and send the amplified sinusoidal wave voltage to the instrument motor.

[0105] In some embodiments of the present invention, the circuit layout of the inverter power supply adopts a modular approach, that is, different functional modules (such as rectifier module, inverter module, control module, etc.) are arranged separately to reduce electromagnetic interference between them. At the same time, in order to reduce heat concentration, high-power devices can be dispersed and sufficient heat dissipation space can be left around key devices.

[0106] Embodiment 4:

[0107] In some embodiments of the present invention, see Figure 3 , step 200 comprises:

[0108] Step 201: closing or opening two switches among the plurality of switches at a preset frequency to generate an AC voltage;

[0109] Step 202: Perform capacitor filtering on the AC voltage to generate the sinusoidal wave voltage.

[0110] In step 201 and step 202, specifically, a SiC switch tube is used to build a Figure 1 The primary side of the single-phase bridge inverter circuit shown in the figure. The circuit receives a drive signal from the FPGA, and the switch T 1 、T 4 Closed, T 2 、T 3 Disconnect:u 0 =U d ; Switch T 1 、T 4 Disconnect, T 2 、T 3 Closed: u 0 =-U d ; When the frequency f s Alternate switch T 1 、T 4 and T 2 、T 3 When the load transformer is connected to the load, an alternating voltage waveform (positive and negative alternating square wave) is obtained, and its period T s =1 / f s , which converts the DC voltage E into an AC voltage u o , and then it is filtered by capacitors to form a sinusoidal voltage.

[0111] In some embodiments of the present invention, see Figure 4 , the power supply method suitable for underground environment applied to the inverter power supply suitable for underground environment also includes:

[0112] Step 400: Monitor the voltage and output current of the battery through the FPGA main control unit in the main control unit.

[0113] In some embodiments of the present invention, see Figure 5 , the power supply method suitable for underground environment applied to the inverter power supply suitable for underground environment also includes:

[0114] Step 500: The battery usage power, supply current, accumulated usage time and supply voltage are stored in a processor via the FPGA main control unit to generate a battery usage result.

[0115] In step 400 and step 500, see Figure 6The battery measurement circuit connects a 100mΩ current sampling resistor in series to the negative end of the power supply circuit output by the battery pack of the battery short section. The current sampling resistor uses a 275℃ high-temperature, high-power, low-resistance resistor. When the battery short section is connected to the load instrument, a loop is formed. The current range through the sampling resistor is generally 300mA~1A, and the voltage range across the sampling resistor is generally 30mV~100mV; at the same time, a low-power dual op amp AD8634 is used to amplify the voltage across the sampling resistor by 20 times and then send it to the FPGA main control unit for collection; after the battery voltage is divided by the voltage divider resistor, it is isolated by the follower and sent to the FPGA main control unit for collection.

[0116] When the battery short section is connected to other circuit short sections for power supply, the FPGA main control unit stores the battery usage, power supply current, cumulative usage time and power supply voltage in the electrically erasable programmable read only memory (EEPROM) inside the processor. Each time the instrument is powered on, the timing and current collection are started and accumulated and stored respectively.

[0117] In some embodiments of the present invention, see Figure 7 , the power supply method suitable for underground environment applied to the inverter power supply suitable for underground environment also includes:

[0118] Step 600: Send the battery usage result to the ground system via the 485 bus communication unit.

[0119] The ground system can query the stored data in real time through the 485 bus communication mode to timely grasp the battery status. Preferably, after replacing the new battery assembly, the ground system can receive a battery power clearing command to clear the stored data and restart the recording of the battery power usage and accumulated usage time.

[0120] Embodiment five:

[0121] To further illustrate the present solution, the present invention also provides a specific application example of a power supply method suitable for an underground environment applied to the inverter power supply suitable for an underground environment, see Figure 8 , the method comprises the following steps:

[0122] S1: Generate fixed frequency pulses through the FPGA main control unit and use PWM to drive subsequent circuits.

[0123] Specifically, a fixed-frequency pulse signal is multiplied by a variable modulation signal to generate an output signal with an adjustable average value. The width of the pulse represents the amplitude of the signal, and the period of the pulse represents the frequency of the modulation signal. The average energy of the output signal can be controlled by changing the duty cycle of the pulse width. This method has the following advantages:

[0124] High efficiency: Since the average power of the output signal can be controlled by adjusting the pulse width, PWM technology can achieve efficient energy conversion. Compared with linear modulation technology, PWM technology can reduce power loss and improve the energy efficiency of the system.

[0125] Accuracy: PWM technology can achieve precise output control. By adjusting the pulse width and frequency, the output signal amplitude, frequency and phase can be precisely controlled.

[0126] Good output signal quality: The output signal generated by PWM technology is a pulse signal with a fixed frequency and an adjustable average value, which can get a smooth analog signal at the output. This makes PWM technology very useful in applications such as audio, power conversion and motor control.

[0127] S2: Generates fixed frequency low voltage AC power through H bridge method.

[0128] In the specific application example of the present application, the H-bridge is composed of four switching elements (usually transistors or MOSFETs), forming a structure similar to the letter "H". Its working principle is to control the on and off states of the four switching elements to change the polarity and magnitude of the power supply voltage applied to the load, thereby achieving forward, reverse and speed control of the motor or load.

[0129] There are two basic operating modes of an H-bridge: unidirectional and bidirectional.

[0130] Unidirectional H-bridge mode: In a unidirectional H-bridge, two diagonal switching elements are turned on at the same time, and the other two switching elements are in the off state. In this way, the power supply voltage will be applied to the load to achieve forward operation. When operating in the reverse direction, the two diagonal switching elements are turned off, and the other two switching elements are turned on, changing the polarity of the power supply voltage and causing the load to operate in the reverse direction.

[0131] Bidirectional H-bridge mode: In a bidirectional H-bridge, four switching elements operate through appropriate control logic. When two diagonal switching elements are turned on and the other two switching elements are turned off, the power supply voltage is applied to the load to achieve forward operation. When two diagonal switching elements are turned off and the other two switching elements are turned on, the polarity of the power supply voltage is changed to make the load run in the reverse direction. The advantages of the H-bridge include: The H-bridge can achieve forward and reverse operation, thereby achieving bidirectional control. By controlling the on and off states of the switching elements, precise control of the motor or load can be achieved, including speed, steering and braking. The H-bridge can achieve efficient energy conversion, and the power supply voltage can be effectively applied to the load to reduce energy loss.

[0132] S3: A fixed-ratio high-temperature transformer is used to achieve a stable output of 220V, 50Hz AC power at 175°C.

[0133] S4: Real-time monitoring of battery voltage and current through FPGA to achieve precise control of battery power and safe use of high-temperature lithium batteries; at the same time, the battery power information is stored in EEPROM to provide a reference for subsequent use.

[0134] S5: Heating test.

[0135] The test was carried out at 175℃ in a heating box, and the test data is shown in Table 1. The conversion efficiency under the load of the inverter plus the motor was mainly tested. The inverter was powered by a high-power DC power supply, and the motor was a 220AC single-phase AC motor used for high-temperature storage logging instruments. The test results showed that the inverter efficiency could reach more than 85% when it was unloaded.

[0136] Table 1

[0137]

[0138] From the above description, it can be seen that an embodiment of the present invention provides a power supply method suitable for an underground environment, including: in response to a power supply instruction, a plurality of control signals are generated by a main control unit, the voltage signals in each group of control signals have the same frequency and a phase difference of 180°; a plurality of switches in a power drive unit are closed and opened in a preset manner, and a sinusoidal wave voltage is generated according to the plurality of control signals; the sinusoidal wave voltage is amplified by a power transformer, and the amplified sinusoidal wave voltage is sent to the instrument motor.

[0139] The power supply method suitable for underground environment provided by the present invention can monitor the voltage and output current of the high temperature lithium battery in real time, and monitor the power of the high temperature lithium battery in real time. Finally, the remaining power of the high temperature lithium battery can be stored and uploaded to the instrument.

[0140] Embodiment six:

[0141] The embodiments of the present application also provide a specific implementation of an electronic device capable of implementing all steps of the power supply method suitable for an underground environment in the above embodiments, see Fig. 9 , electronic equipment specifically includes the following:

[0142] Processor (processor) 1201, memory (memory) 1202, communication interface (CommunicationsInterface) 1203 and bus 1204;

[0143] The processor 1201, the memory 1202, and the communication interface 1203 communicate with each other through the bus 1204; the communication interface 1203 is used to realize information transmission between the server device and the client device and other related devices;

[0144] The processor 1201 is used to call the computer program in the memory 1202. When the processor executes the computer program, all steps in the power supply method applicable to the underground environment in the above embodiment are implemented. For example, when the processor executes the computer program, the following steps are implemented:

[0145] Step 100: In response to the power supply instruction, a plurality of control signals are generated by the main control unit, wherein the voltage signals in each control signal have the same frequency and a phase difference of 180°;

[0146] Step 200: performing preset closing and opening operations on a plurality of switches in the power drive unit, and generating a sinusoidal wave voltage according to the plurality of control signals;

[0147] Step 300: Amplify the sinusoidal wave voltage through a power transformer, and send the amplified sinusoidal wave voltage to the instrument motor.

[0148] Embodiment seven:

[0149] The embodiments of the present application also provide a computer-readable storage medium capable of implementing all the steps of the power supply method applicable to the underground environment in the above-mentioned embodiments. The computer-readable storage medium stores a computer program. When the computer program is executed by a processor, all the steps of the power supply method applicable to the underground environment in the above-mentioned embodiments are implemented. For example, when the processor executes the computer program, the following steps are implemented:

[0150] Step 100: In response to the power supply instruction, a plurality of control signals are generated by the main control unit, wherein the voltage signals in each control signal have the same frequency and a phase difference of 180°;

[0151] Step 200: performing preset closing and opening operations on a plurality of switches in the power drive unit, and generating a sinusoidal wave voltage according to the plurality of control signals;

[0152] Step 300: Amplify the sinusoidal wave voltage through a power transformer, and send the amplified sinusoidal wave voltage to the instrument motor.

[0153] Each embodiment in this specification is described in a progressive manner, and the same or similar parts between the embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the hardware + program embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiment.

[0154] The above is a description of a specific embodiment of the present specification. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recorded in the claims can be performed in an order different from that in the embodiments and still achieve the desired results. In addition, the processes depicted in the accompanying drawings do not necessarily require the specific order or continuous order shown to achieve the desired results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0155] Although the present application provides method operation steps such as embodiments or flow charts, more or fewer operation steps may be included based on conventional or non-creative labor. The order of steps listed in the embodiments is only one way of executing the order of many steps and does not represent the only execution order. When the actual device or client product is executed, it can be executed in the order of the method shown in the embodiments or the drawings or in parallel (for example, in a parallel processor or multi-threaded processing environment).

[0156] For the convenience of description, the above devices are described in various modules according to their functions. Of course, when implementing the embodiments of this specification, the functions of each module can be implemented in the same or more software and / or hardware, or the module implementing the same function can be implemented by a combination of multiple sub-modules or sub-units. The device embodiments described above are only schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0157] Those skilled in the art also know that, in addition to implementing the controller in a purely computer-readable program code, the controller can be made to implement the same function in the form of logic gates, switches, application-specific integrated circuits, programmable logic controllers, and embedded microcontrollers by logically programming the method steps. Therefore, such a controller can be considered as a hardware component, and the devices for implementing various functions included therein can also be considered as structures within the hardware component. Or even, the devices for implementing various functions can be considered as both software modules for implementing the method and structures within the hardware component.

[0158] In a typical configuration, a computing device includes one or more processors (CPU), input / output interfaces, network interfaces, and memory.

[0159] The memory may include non-permanent storage in a computer-readable medium, random access memory (RAM) and / or non-volatile memory in the form of read-only memory (ROM) or flash RAM. The memory is an example of a computer-readable medium.

[0160] Each embodiment in this specification is described in a progressive manner, and the same and similar parts between the embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the system embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiment. In the description of this specification, the description of the reference terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the embodiment of this specification. In this specification, the schematic representation of the above terms does not necessarily target the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, in the absence of contradiction, a person skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0161] The above is only an example of the embodiment of the present specification and is not intended to limit the embodiment of the present specification. For those skilled in the art, the embodiment of the present specification may have various changes and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the embodiment of the present specification shall be included in the scope of the claims of the embodiment of the present specification.

Claims

1. An inverter power supply applicable to underground environments, characterized in that, it includes: a main control unit, a power drive unit, and a power transformer, where: the main control unit includes an FPGA main control unit and at least one follower drive unit; the power drive unit is connected to the FPGA main control unit through the follower drive unit, and is connected to the power transformer, and the primary circuit of the single-phase bridge inverter circuit in the power drive unit is made of SiC switching tubes.

2. The inverter power supply applicable to underground environments according to claim 1, characterized in that, it further includes: an undervoltage control circuit and a current limiting control circuit, where: both the undervoltage control circuit and the current limiting control circuit are connected to the FPGA main control unit; the undervoltage control circuit is used to monitor the voltage of the inverter power supply; the current limiting control circuit is used to monitor the current of the inverter power supply.

3. The inverter power supply applicable to underground environments according to claim 2, characterized in that, it further includes: a DC voltage monitoring circuit, a DC current monitoring circuit, and an analog-to-digital conversion circuit, where: the undervoltage control circuit and the current limiting control circuit are connected to the power drive unit through the DC voltage monitoring circuit, the DC current monitoring circuit, and / or the analog-to-digital conversion circuit.

4. The inverter power supply applicable to underground environments according to claim 3, characterized in that, it further includes: an AC voltage monitoring circuit, an AC current monitoring circuit, a signal voltage dividing circuit, and a rectifying circuit, where: the DC voltage monitoring circuit, the DC current monitoring circuit, and the analog-to-digital conversion circuit are connected to the power transformer through the AC voltage monitoring circuit, the AC current monitoring circuit, the signal voltage dividing circuit, and / or the rectifying circuit.

5. The inverter power supply applicable to underground environments according to claim 1, characterized in that, it further includes: a 485 bus communication unit for transmitting the battery usage result of the inverter power supply to the ground system; and the step-up ratio of the power transformer is 1:

2.

6. A power supply method applicable to underground environments for the inverter power supply applicable to underground environments according to any one of claims 1 to 5, characterized in that, it includes: in response to a power supply instruction, generating multiple groups of control signals through the main control unit, where the voltage signals in each group of control signals have the same frequency and a phase difference of 180°; by performing preset closing and opening operations on multiple switches in the power drive unit, and generating a sine wave voltage according to the multiple groups of control signals; amplifying the sine wave voltage through the power transformer and sending the amplified sine wave voltage to the instrument motor.

7. The power supply method applicable to underground environments according to claim 6, characterized in that, the step of performing preset closing and opening operations on multiple switches in the power drive unit and generating a sine wave voltage according to the multiple groups of control signals includes: closing or opening two switches among the multiple switches at a preset frequency to generate an AC voltage; performing capacitor filtering on the AC voltage to generate the sine wave voltage.

8. The power supply method applicable to the underground environment according to claim 6, characterized in that, it further includes: monitoring the voltage and output current of the battery through the FPGA main control unit in the main control unit.

9. The power supply method applicable to the underground environment according to claim 8, characterized in that, it further includes: storing the power consumption, supply current, cumulative usage time, and supply voltage of the battery in the processor through the FPGA main control unit to generate a battery usage result.

10. The power supply method applicable to the underground environment according to claim 9, characterized in that, it further includes: sending the battery usage result to the ground system through the 485 bus communication unit.

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