Explain the working principle of the brake unit circuit:
The working principle of the brake unit circuit is as follows: When the motor decelerates under the effect of an external force and is in the power generation state, it will generate regenerative energy. Its three-phase AC EMF is rectified by the three-phase full-control bridge composed of six free-wheeling diamonds in the frequency changer, causing the voltage of the DC-bus in the frequency changer to continue to rise. When the direct current voltage reaches the starting voltage of the brake unit (such as DC690V), the power switch tube in the brake unit is turned on, and the current flows through the brake resistance. The brake resistance releases heat to absorb regenerative energy, causing the motor speed to decrease, and at the same time, the voltage of the frequency changer's direct current bus to decrease. When the voltage of the direct current bus drops to the stopping voltage of the brake unit (such as DC690V), the power tube of the brake unit is turned off. At this time, no brake current flows through the resistance, and the brake resistance naturally dissipates heat and lowers temperature. When the voltage of the direct current bus rises again, the brake unit will be activated. The above process will be repeated to balance the bus voltage and ensure the normal operation of the system. In addition, the brake unit is composed of a high-power transistor-GTL and its driving circuit. Its function is to increase the speed of consuming regenerative electric energy by adding an external brake component when the discharge current part of the current link cannot be stored within the specified voltage range or the internal braking resistance cannot be consumed in time, causing the direct current part to be "over-pressured". In some applications that require rapid deceleration, according to the principle of the induction motor, when the deceleration rate increases, the brake moment increases, the system deceleration time is greatly shortened, the energy feedback is accelerated, and the voltage of the direct current bus rises rapidly. At this time, the brake unit system can quickly consume the energy.(The energy is converted into heat energy by the braking resistance), which makes up for the shortcomings of the ordinary frequency changer, such as slow braking speed and small braking moment (less than 20% of the rated moment). It is suitable for cranes and other potential energy loads and occasions that need to be quickly braked but are short-term work systems. Read more exciting novels for free
What does it mean to reverse the control circuit and explain the working principle?
The reverse rotation control circuit was a circuit used to control the forward and reverse rotation of the motor. The working principle was as follows: - ** Contactor Interlock Positive and Negative Rotation Control Circuit **: - ** Forward Rotation **: Press the Forward Rotation Start button (such as SSB2), and the coil of the Forward Rotation Contactor (such as Km1) will be energized. The Km1 auxiliary normally open contact is closed to achieve self-locking, ensuring that the circuit remains connected after the button is released; the Km1 auxiliary normally closed contact is disconnected and interlocked with the reversing contact (Km2) coil to prevent simultaneous power-on. At the same time, the main contact of Km1 was closed, and the motor was powered up and began to rotate forward. - ** Reverse **: Press the reverse start button (like SSB3), and the Km2 coil will be energized. The Km2 auxiliary normally open contact is closed and self-locked, and the Km2 auxiliary normally closed contact is disconnected, causing the Km1 coil to lose power (forming an interlocked). The Km1 main contact is reset, the Km2 main contact is closed, and the motor runs in reverse. - ** Double Interlock Positive and Negative Rotation Control Circuit of the Button-Contactor **: Add the Button-Contactor Interlock to the Contactor Interlock. The normally closed contact of the reverse start button is connected in series with the coil of the contactors that control the forward rotation, and the normally closed contact of the forward start button is connected in series with the coil of the contactors that control the reverse rotation. This was equivalent to double insurance, further ensuring that the positive and reverse contactors would not be energized at the same time, improving the safety and reliability of the circuit. The principle of the positive and negative rotation control in the ladder diagram was similar: - Two start-stop circuits were used to control the forward and reverse rotation of the motor. Pressing the forward start button (such as SSB2), the corresponding input point (such as X0) will turn ON, and its normally open contact will be connected, so that the coil of the output point (such as Y0) will be "energized" and self-protect, so that the coil of the forward rotating contactors (such as KM1) will be energized, and the motor will rotate forward. - Pressing the stop button (such as SSB1), the corresponding input point (such as X2) will turn ON, and its normally closed contact will be disconnected, causing the coil of the forward output point (such as Y0) to "lose power" and the motor will stop running. - In order to ensure that the forward and reverse rotation do not work at the same time, the normally closed contacts of the forward rotation output point (such as Y0) and the reverse rotation output point (such as Y1) are connected in series with each other's coil to achieve interlocked connection; and the button is interlocked, that is, the normally closed point of the reverse rotation start button is connected in series with the coil of the output point (such as Y0) that controls the forward rotation, and the normally closed contact of the forward rotation start button is connected in series with the coil of the output point (such as Y1) that controls the reverse rotation. In this way, when the motor was rotating forward, if it wanted to change to reverse operation, it could directly press the reverse start button without pressing the stop button, and through the switching of the contacts, it could realize forward transformation and reverse rotation. In addition, there are often overload protection components in the circuit, such as thermal relay (FT). When the induction motor is seriously overloaded for a long time, after a certain delay, the thermal relay will act, and its normally closed contact will be broken. When it is connected in series with the coil of the contactors, it can make the coil of the contactors cut off, and the motor will stop running, playing a protective role. Some thermal relay needed to be manually reset, and some had an automatic reset function. During the circuit connection and use, the connection position of the contacts needed to be reasonably arranged according to its characteristics to ensure safe operation. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
Try to analyze the working principle of reverse brake
Reversed brake appeared when the potential load moment exceeded the electromagnetic moment. For example, when a crane was lowering a heavy object, this working state was often used to control the descending speed. The principle was that under normal circumstances, when the weight rose at the rated speed, the relevant contactors were connected, and the external resistance in the rotor-circuit was cut off; when the weight fell, the relevant contactors were cut off, and all the resistance was connected to the rotor-circuit, which caused the critical point of the mechanical characteristics to move down significantly. At this time, the power supply was still connected, but the motor was reversed, thus forming a reverse brake. In this braking state, the mechanical power input into the motor shaft was converted into electric power, which was consumed by the resistance of the motor circuit together with the electromagnetic power transmitted from the motor. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
How do you look at the internal circuit diagram of the brake unit?
Explain the circuit of the cell phone unit
The circuit of the cell phone unit includes many parts. 1. ** Amplification **: Its function is to amplify the AC signal. Due to the long transmission distance from the base station to the mobile phone antenna, the radio signal entering the mobile phone was weak. In order to further process the signal, it had to be amplified first. According to the type of signal, it can be divided into low-frequency amplifier, intermediate-frequency amplifier, radio frequency amplifier, and radio frequency power amplifier. 2. ** Oscillator **: It is widely used in electronic equipment. The main technical indicators are the accuracy, stability, and amplitude of the frequency. Oscillators require a direct current power source to provide energy, and can convert the direct current power source into alternating current oscillation energy, similar to an amplifier in this function. 3. ** Mix **: For superheterodyne-type and direct-conversion receiver, the high-frequency signal needs to be converted once during reception; for double-superheterodyne-type receiver, it needs to be converted twice, and this work is completed by the mixing circuit. 4. ** Electronic switch circuit **: The working state of the triode has saturation and cut-off. The electrical signal used for control is provided by the logic circuit. The circuit devices used to realize the electronic switch could be triode, field effect tube, integrated circuit, etc. 5. ** filter **: It has two main functions: one is to filter useful signals and suppress interference; the other is to achieve the function of matching the resistance to obtain a larger transmission power. According to the signal filtering characteristics, it could be divided into four types: low-pass, high-pass, band-pass, and band-stop. In addition, the mobile phone also included a radio frequency circuit, a voice circuit, a processor and memory circuit, a power supply and charging circuit, an operation and screen display circuit, and an interface circuit. The radio frequency circuit was responsible for receiving and transmitting signals, while the processor and memory circuit were responsible for processing information and storing data. In the circuit system of the smartphone, the radio frequency circuit used the method of directly reconstructing the received base band information, which simplified the traditional superheterodyne-frequency conversion process and improved efficiency. It also integrated functions such as frequency combining and receiving voltage controlled oscillations, reducing the use of external components, reducing costs, and improving reliability. At the same time, there was a smart antenna system, a power amplifier circuit, a receiver circuit, a transmitter circuit, a frequency synthesize, a system logic control part, an audio signal processing part, an I/O interface, a power supply circuit, a boost circuit, a negative pressure generator, an internal charger, a touch screen circuit, a camera circuit, and other unit circuits. Together, they constituted the mobile phone circuit system and realized various functions of the mobile phone. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
Working Principle of Reverse Connection Control Circuit of Three-phase Induction Machine
The working principle of the three-phase induction motor reverse connection control circuit is as follows: 1. Reverse braking was completed with the help of the speed relay SD. There was a heavy object in the speed relay mechanically connected to the motor shaft. 2. After pressing the start button, the motor of the SSB1 rotated to a certain speed. Due to the inertia, the weight pressed the speed relay micro-switch to send a signal, and the SD contact was connected. 3. When the stop button SSB0 is pressed, the KM1 loses power, and the motor enters the free parking state instantly after being disconnected from the power supply; after the normally closed contact of the KM1 recovers, the KM2 is energized, and the motor enters the braking state after being connected with the reverse power supply; when the speed of the motor drops and is lower than the speed at which the speed relay contacts are pressed together, the speed relay micro switch is disconnected, and the motor enters the free parking state again until it completely stops. 4. For KM1 and KM2, AC contactors with mechanical interlocks shall be selected, and their normally closed contacts shall be set with electrical interlocks to ensure safety. 5. Circuit breakers QF1 and QF2 are used for short-circuit protection, and thermal relay KH is used for long-term overload protection of the motor. 6. The resistance R was used to adjust the brake strength. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
Phaeton brake electronic control unit code error
If the electronic control unit of the Phaeton brake is incorrectly programmed, the electronic handbrake module needs to be recoded and the basic settings and brake gap adjustment needs to be carried out. If the new control unit was not codified or the code was lost, the code of the original control unit must be read before replacing the control unit. If the code of the original control unit could not be read, the corresponding code must be found with the part number. If the code is entered incorrectly, there will be an unknown fault code. Different part numbers and model year code values are different. After the code is completed, it may be necessary to make basic settings for the fault code (such as 01087) that has not been implemented. The method is to enter Special Function → Choose Electronic Park → and then set the release and recovery function.(e.g. Fault code 01279). After the above fault code processing is completed, the brake control unit-read fault code (e.g. Fault code 01316) will be automatically cleared. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
The working principle of oil extraction
The working principle of oil extraction included geological exploration, drilling, oil extraction, and transportation. The location and nature of the oil reservoir can be determined through geological survey and geological survey. Well drilling was the process of passing a drill bit through the earth and into the oil reservoir. Oil extraction was the process of extracting oil from a reservoir. Transportation was the process of transporting the extracted oil to its destination. The specific mining methods included natural pressure mining, artificial pumping, water flooding, and gas flooding.
The working principle of 2D and 3D
The working principles of the 2D and 3D are different. You can refer to the following explanation: Two-dimensional refers to the fictional two-dimensional world that usually appears in anime, comics, games, and other media. In the 2D world, characters, scenes, and things were flat, and the colors and shapes were simple geometric shapes. The working principle of 2D was based on the projection principle by projecting an image onto a two-dimensional plane to create a virtual world. The three-dimensional world refers to the real world we live in. In the three-dimensional world, characters, scenes, and things were all three-dimensional, and the colors and shapes were all complicated. The working principle of the three-dimensional world was based on the principle of perspective. By observing an object from different angles and distances, one could obtain its shape, size, position, and other characteristics. Therefore, the difference between the working principle of 2D and 3D was that they were based on different principles and presentation methods.
The working principle of the cvl transmission
The CVS transmission was mainly composed of two variable diameter rollers (shaped like a pair of cones) and a steel belt or chain. One of the rollers was connected to the engine (power input) and the other was connected to the drive shaft (power output). During operation, the transmission ratio was changed by changing the diameter of the rollers (that is, the contact diameter between the cone and the steel belt or chain). For example, when driving at a low speed, the diameter of the input end of the wheel was smaller and the speed was higher, while the diameter of the output end of the wheel was larger and the speed was lower. As the speed of the car increased, the diameter of the two wheels changed, causing the speed of the output end of the wheel to increase. According to the different power transmitting devices, it could be divided into steel belt CVs and chain CVs. When the steel-belt CVS works, the driving cone wheel presses the side of the steel belt formed by the overlapping of the metal sheets and the metal rings to form static friction force, and the hardness between the push sheet materials is used to form thrust force, so that the steel belt drives the driven cone wheel to rotate to transmit power. When the driving wheel is clamped to the middle by the oil pressure device, the steel belt moves upward along the side wall, the circumference of the driving wheel increases, and the circumference of the driven wheel decreases, thus realizing the amplification of the engine's torque-force. The chain of the chain-type CVS was composed of a ring-shaped steel sheet and a pull piece. When it worked, the chain did not directly contact the cone wheel, but the middle rocking arm pin was pressed to achieve the transmission of the moment. The novel "Watching the Moon on Fish Island" is equally exciting. Everyone is welcome to click and read it!
The Principle of Controlling the Circuit of the Dimmer Lamp with a Single Switch
The core technology of the dimming lamp was its built-in dimming circuit and sensing device. When a single-connected switch controls a dimmer, for dimmer lamps that adjust brightness by changing the current intensity (commonly used in incandescent lamps and halo lamps), the single-connected switch may adjust the current intensity by changing the resistance in the circuit, thus changing the brightness of the light; For dimmer lamps that control the brightness of the light by changing the current frequency (applicable to LED lamps and fluorescent lamps), the single-connected switch may change the frequency of the current through relevant circuit components to achieve the brightness of the light. At the same time, the dimming lamp can detect the change of the surrounding light or sound through infrared, light sensing or voice control sensors. The single-connected switch plays a role in coordinating with the circuit to achieve overall control in this process. For example, after the sensor detection conditions are met, the single-connected switch control circuit realizes the corresponding current intensity or frequency adjustment, thereby achieving the dimming effect. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>