What are the braking methods of the inverter? Generally speaking, braking refers to the technical measures taken during the operation of the motor due to fault protection or man-made active shutdown, and the commonly used inverter braking methods include energy consumption braking, feedback braking, DC braking and DC feedback braking.
1. Energy consumption braking
The energy consumption braking mode uses the chopper and braking resistor, and uses the braking resistor set in the DC circuit to absorb the regenerative electric energy of the motor and realize the rapid braking of the inverter.
The advantages of energy consumption braking: simple structure, no pollution to the power grid (compared with the feedback system), low cost;
Disadvantages of energy-consumption braking: low operating efficiency, especially in frequent braking, a large amount of energy will be consumed and the capacity of the braking resistor will increase.
2. Feedback braking
The feedback braking mode is to use active inverter technology to invert the regenerative electric energy into alternating current at the same frequency and phase as the power grid and send it back to the power grid, so as to achieve braking. To achieve energy feedback braking, it requires voltage and frequency and phase control, feedback current control and other conditions.
The advantages of feedback braking: it can operate in four quadrants, and the electric energy feedback improves the efficiency of the system;
Disadvantages of feedback braking: (1) This feedback braking method can only be used under a stable grid voltage that is not prone to failure (the grid voltage fluctuation is not more than 15%). Because when the grid voltage failure time is greater than 2ms during the power generation braking operation, the commutation failure may occur and the device will be damaged. (2) When giving back, there is harmonic pollution to the power grid; (3) The control is complex and the cost is high.
3. DC braking
DC braking, generally refers to when the output frequency of the inverter is close to zero and the motor speed is reduced to a certain value, the inverter reverses to the stator winding of the asynchronous motor to pass into the DC to form a static magnetic field, at this time, the motor is in a state of braking with energy consumption, and the rotor is rotated to cut the static magnetic field and generate braking torque, so that the motor stops quickly.
It can be used in situations where accurate parking is required or for irregular rotation of the brake motor due to external factors before starting.
1. Elements of DC braking
(1) DC braking voltage value, the essence is to set the size of the braking torque, obviously the greater the inertia of the drag system, the DC braking voltage value should be correspondingly larger, the general DC voltage in about 15-20% of the rated output voltage of the inverter is about 60-80V, and some use the percentage of braking current;
(2) DC braking time, that is, the time when DC current is introduced to the stator winding, it should be slightly longer than the actual required shutdown time;
(3) DC braking starting frequency, when the working frequency of the inverter drops to how big it becomes, it begins to change from energy consumption braking to DC braking, which is related to the load requirements for braking time, if there is no strict requirement, the DC braking starting frequency is set as small as possible;
Fourth, DC feedback braking
The principle of the shared DC bus feedback braking mode is: the regenerative energy of motor A is fed back to the common DC bus, and then its regenerative energy is consumed through motor B;
The shared DC bus feedback braking mode can be divided into two modes: shared DC balanced bus feedback braking and shared DC loop bus feedback braking;
1. Shared DC equalization bus feedback braking: The shared DC equalization bus feedback braking method is to use the connection module to connect to the DC circuit bus. The connection module includes a reactor, a fuse and a contactor, which must be individually designed on a case-by-case basis. Each inverter is relatively independent and can be connected to or off the DC bus as needed.
2. Shared DC circuit bus feedback braking: The shared DC circuit bus feedback braking method is to connect the inverter part to a common DC bus only.
|
More on that
|
Hollysys edge intelligent controller and edge intelligent all-in-one machine launched new products
Transportation power, urban rail responsibility. With the vigorous development of emerging technologies such as 5G, cloud computing, big data, and artificial intelligence, more innovative technologies are accelerating the empowerment of urban rail transit, and smart urban rail is ushering in a "golden age" of development. As a deep cultivator in the field of smart urban rail, Hollysys adheres to technological innovation.
|
|
Megmeet inverter - the selection principle and precautions of the inverter
1. Select the inverter according to the load characteristics
A: Fans and pumps are the most common loads: the requirements for the inverter are the simplest, as long as the inverter capacity is equal to the capacity of the motor (air compressors, deep water pumps, sediment pumps, and fast-changing music fountains need to increase their capacity).
...
|
|
Megmeet PLC - What are the steps to complete PLC commissioning?
1. Check the circuit according to the drawing (without power transmission)
The drawings of the general PLC system include two parts: the drawings in the cabinet and the drawings outside the cabinet; The drawing in the cabinet refers to the wiring diagram inside the cabinet; The out-of-cabinet drawings are the wiring diagrams of all electrical cabinets.
This part needs to be checked for;
...
|
|
Megmeet inverter - what are the control methods of the inverter?
Sinusoidal Pulse Width Modulation (SPWM) control mode
It is characterized by simple structure of control circuit, low cost, good hardness of mechanical characteristics, and can meet the smooth speed regulation requirements of general transmission, and has been widely used in various fields of industry. However, this type of control is at low frequencies, ...
|
|
Megmeet drives – what are the basic requirements for regular replacement of drive components?
1. It is necessary to figure out the basic parameters and shape of the device that needs to be replaced. The basic parameters include the rated operating current, the capacitance of the capacitor, the resistance value of the resistor, the value of the GTR Darlington device (current amplification factor), the switching characteristics of the IGBT (including IPM) device, and the saturation voltage ...
|
|
Megmeet PLC - the basic composition of PLC
a. Power supply
The power supply of the PLC plays a very important role in the whole system. It can't work properly without a good and reliable power supply system, so PLC manufacturers also attach great importance to the design and manufacture of power supplies. General AC voltage fluctuations are +10% (+15%) ...
|
|
Megmeet PLC - an introduction to the classification of PLC
There are many types of PLC products, and their specifications and performance also vary. PLCs are usually classified according to their different structural forms, differences in functions, and the number of I/O points.
2.1 Classification by structural form
According to the structural form of PLC, PLC can be divided into whole ...
|
|
Megmeet PLC - What is the difference between PLC and MCU?
1. PLC is a relatively mature control system composed of single-chip microcomputer, which is the product of a mature and stable single-chip microcomputer application system that has been debugged. It is highly versatile.
2. The single-chip microcomputer can form a variety of application systems, and the application range is wider. In the case of a single "microcontroller", it ...
|
|
Megmeet PLC - the difference between PLC and frequency converter
1. The role is different
A PLC (Programmable Logic Controller) is an electronic system designed for digital operations in an industrial environment.
The inverter is the application of frequency conversion technology and microelectronics technology to control the AC motor by changing the frequency of the motor working power supply.
|
|
Megmeet Inverter - Precautions for the Use of Inverter (1-10)
1. The inverter must be selected correctly.
2. Read the product manual carefully, and wiring, installation and use in accordance with the requirements of the manual.
3. The inverter device should be reliably grounded, and the radio frequency interference should be suppressed to prevent the inverter from causing electric shock due to leakage.
4、 ...
|
|
Megmeet inverters – seven areas of application for high-voltage inverters
1. Metallurgical industry - the application of high-voltage inverter in the metallurgical profession mainly includes plate and wire rod rolling mills, coilers, fans, slurry pumps, etc., with the primary intention of motor energy saving.
2. Electric power industry - China's power generation capacity ranks second in the world, second only to United States. The power profession is also changing.
|
|
Megmeet drives – the replacement steps for high-voltage drive power units
1) Shut down, so that the inverter out of the operating state;
2) Cut off the high-voltage power supply and push out the high-voltage cabinet trolley (when there is a bypass cabinet. The inverter can be isolated by the disconnecting switch of the bypass cabinet), the local or remote high-voltage disconnect switch can be locked, and the high-voltage cabinet grounding switch can be grounded;
3) Hit ...
|
|
Megmeet welding machine - resistance welding or laser soldering who is more suitable for electronics industry applications
Today's electronics industry revolves around high-speed communication and supercomputing on the Internet, and the requirements for electronic products are getting higher and higher. A large number of micro-precision electronic products are constantly testing the response speed and level of major enterprises in the market. Electronics manufacturers perform real-time, accurate ...
|
|
Megmeet inverters – Routine maintenance of high-voltage inverters requires precautions
1. The operating ambient temperature of the inverter (mainly refers to the air temperature of the air inlet of the power unit cabinet) requires a minimum ambient temperature of -5 °C and a maximum ambient temperature of 40 °C. In order to improve the reliability and extend the service life of the drive, check the following items:
Air conditioning and refrigeration ...
|
|
Megmeet PLC - the characteristics of the working process of PLC
1. The PLC adopts the mode of centralized sampling and centralized output, which can reduce the influence of external interference.
2. The working process of PLC is the process of cyclic scanning. The duration of the cyclic scan depends on the speed of execution of the instructions and the length of the user's program.
3. Output to input ...
|
|
Megmeet inverter - 5 precautions for the use of inverter
1. The circuit board inside the inverter belongs to precision electronic components, which needs to be moisture-proof and dust-proof, and the temperature and humidity are not too high, and cannot be installed on the bare wall, so the inverter should be installed in the middle of the control cabinet; The inverter should be installed vertically, and the installation should be avoided directly above and below ...
|
|
Megmeet PLC - Comparison of the advantages of PLC and DDC in building automation systems
1. Application field: The initial design goal of PLC is only to replace complex relay circuits, and DDC is originally only used in industrial automation instruments: PLC emphasizes versatility, DDC emphasizes specificity: PLC is used in the field of industrial control, and DDC is used in professional building systems.
2. Structural differences ...
|
|
Megmeet PLC - What are the main components of PLC control cabinet?
1. Air switch
Air switch is also called air circuit breaker, referred to as air open, is an indispensable component of the control cabinet, usually from the outside into the cabinet of power supply, must go through the air open, in order to reach the inside, the function of air open in addition to the power supply, more as short circuit protection and overload protection...
|
|
Megmeet inverter - the speed regulation method of high-voltage inverter
1. Hydraulic coupling method. That is, a hydraulic coupling device is inserted between the motor and the load in series, and the size of the coupling force between the motor and the load is adjusted by the height of the liquid level, so as to realize the speed adjustment of the load;
2. Cascade speed regulation. Tandem speed regulation must use a wound asynchronous motor, and the rotor ...
|
|
Megmeet Electric participated in the 2021 CHINAPLAS World Rubber and Plastics Exhibition
From April 13 to 16, 2021, CHINAPLAS 2021 was grandly held at the Shenzhen World Convention and Exhibition Center (Bao'an New Hall) with the theme of "New Era· New Power, · Sustainable Innovation".
As a vane of rubber and plastics professions and a barometer of shopping malls, the World Rubber and Plastics Exhibition has a 350,000 square meter ...
|
|
Contact
working hours
