Li Rong said: "You are not in the company?"
Peng Jian said: "I went to the machining factory. Several people were testing there recently."
Li Rong said: "What important projects have been carried out recently?"
Peng Jian said: "We are preparing to build a reservoir."
Prefabricated reservoirs are produced in the factory and then assembled on site and can be installed quickly, thus greatly shortening the construction cycle and saving time and labor costs.
Li Rong said: "You are in the new project team, are you getting used to it?"
Peng Jian said: "Adapt."
Guan Lilong thought for a moment and realized that this sentence was redundant. Peng Jian had the strongest adaptability.
Peng Jian said: "Come back and solder another piece of this circuit board."
Next to him is Jiang Sheng, a new worker.
Li Rong came to his laboratory with Peng Jian and Jiang Sheng.
The position recommended by Peng is an ordinary electrician's table. The steel plate is used as the frame, and the outer surface is sprayed with colorful epoxy polyplastic, which looks sturdy and durable. The desktop is made of high-density fiberboard. He borrowed an oscilloscope from another project team. Bring your own soldering iron and solder. The metal cabinet next to it contained many disassembled circuit boards.
Peng Jian said to Jiang Sheng next to him while doing this.
Draw the wiring of the circuit board, draw the circuit schematic, give the component list, and package library. Divide the board into different functional areas. Ensure good isolation between different voltage areas. Factors such as signal transmission speed, power and electromagnetic interference need to be considered. Minimum line width and spacing requirements must be met.
Solder this patch-type component. There is a row of resistors here. To tin one side of the pad first, heat the soldering iron to tin the pad. Be careful not to add too much tin to prevent the two pads from being connected. Then use tweezers to hold the resistor, place the resistor on the pad, melt the solder and position the resistor at the same time. After placing it, remove the soldering iron and loosen the resistor. Then fix the other end and place the solder wire next to the resistor to tin it.
After welding, he took out the signal transmitter, multimeter, and oscilloscope and started measuring.
The input signal is 1kHz, the output signal is 10kHz, OK, and meets the requirements.
There are some circuits that control the motor. Generally, pulse width modulation signals are used for control.
There are several reasons for using pulse width modulation instead of voltage speed regulation. Pulse width modulation can be used for DC and AC motor speed regulation, and can also be combined with frequency modulation, which is highly versatile. In motor driving, the power amplifier works in a nonlinear state. Pulse width modulation allows the power amplifier to work in a switching state, which can reduce active power consumption and obtain higher efficiency and better linearity. Keeping the motor in a powered state is beneficial to the dynamic characteristics of the motor.
For DC motors, there are three speed regulation methods, namely changing the external voltage, changing the excitation flux and changing the rotor loop resistance speed regulation. Changing the duty cycle of the pulse width modulation signal is equivalent to changing the average voltage applied to the electrode circuit. Changing the duty cycle of the signal can change the speed of the DC motor.
For AC motors, using an AC-DC-AC frequency converter can change the voltage and frequency of the control signal at the same time to keep the magnetic flux constant while changing the speed of the AC motor.
For stepper motors, each phase winding is energized separately, causing the rotor to rotate, which can change the frequency of the input pulse signal. The greater the frequency, the faster the motor rotates.
The control part in CNC machine tools controls the movement of the worktable along the x-axis and y-axis. Control the tool to move up and down along the z-axis. Control the rotation of the tool. So milling CNC machine tools and drilling CNC machine tools basically require 4 motors. The lathe's motor controls the rotation of the blank, and also controls the tool's proximity to the blank. Some CNC machine tools have a tool library, and the manipulator must be controlled to take the tool out of the tool library and place it in the place where the tool is clamped.
The detection part in CNC machine tools. The detection device is used to detect the rotation speed of the motor, the moving speed and displacement of the worktable, and the moving speed and displacement of the tool holder. Resolvers and induction synchronizers can be used to detect the rotational speed. If high detection accuracy is required, a grating sensor can be used to detect the moving speed and displacement of the workbench.
Li Rong said: "What's wrong with these CNC machine tools?"
Peng Jian said: "The motor windings were severely overheated and affected by moisture. Electrical breakdown occurred due to weak insulation between the stator windings."
Li Rong said: "The humidity has been quite high recently."
After returning to the company, Li Rong met Xiao Jiong. He pointed to a location on the map near the edge of the city and said, "You have to look over there to see why these large wind turbines started spinning on their own."
Li Rong said, "Okay. I'll go over and have a look."
Li Rong went to the large motor control area and checked the control circuit and mechanical parts of the fan.
Xiao Jiong said: "Can you find out the reason?"
Li Rong said: "There is no problem with the circuit. The software doesn't know. When the wind blows, will the fan rotate?"
Xiao Jiong said: "No."
Li Rong said: "There must be strong winds recently."
Xiao Jiong said: "It seems there is."
In a certain office building.
Tan Pu said: "Those reservoirs block the flowing ore underground. I hope you can delay it for some time. It won't take long, we need to dig first."
Hyena said: "Okay."
Tan Pu said: "It also needs some water power or other things to assist, as a blocking and offensive weapon."
Hui said: "These are being prepared. We have tried several fans on the edge of the city. We can then use thermal distribution stones to assist in generating cyclones."
