Inverter harmonic calculation method - LS power generation

Create Date: 2024-8-30 12:03:23|Source: LS/Power Generation

1. Method 1

Method 1: Fourier transform to obtain the amplitude and phase of each harmonic of voltage and current, calculate the active power of each harmonic according to P=√3UIcosφ, and add the active power of all harmonics to obtain the harmonic power.

Method 2: Measure the total active power, obtain the fundamental amplitude and phase of voltage and current by Fourier transform, and calculate the fundamental active power according to P=√3UIcosφ, and the total active power minus the fundamental active power is the harmonic power. The accuracy of harmonic power measurement is low, and the higher the harmonic frequency, the lower the accuracy, so the second method is recommended.

Inverter harmonic calculation method - LS power generation

Inverter harmonic calculation method - LS power generation

2. Method 2

1) Primary side of the inverter

The possibility of distortion of the power supply voltage is very small, while the distortion of current harmonics is very likely. It can be used in power calculations

　　P=U*I1*cosa1;

　　S=U*I;

　　PF=P/S=(I1/I)*cosa1;

You can also write a simplified formula of this formula according to the boundary of THDi and DPF; There is a lot of writing in various textbooks.

2) Secondary side of inverter:

According to Zhou Shouchang's "Circuit Principle" and "Non-sinusoidal Periodic Current Circuit Analysis", the power cannot occur between different harmonic voltages and currents, and its product is 0. Then, in addition to the fundamental power, the harmonic power is easy to calculate. Able to write summation symbols (h=1 to ∞) (Uh*Ih*cosah).

More on that

	The basic method and steps of inverter debugging - power inverter 1. No-load energizing test of inverter 1. Ground the grounding terminal of the inverter. 2. Connect the power input terminal of the inverter to the power supply through the leakage maintenance switch. 3. Check whether the factory display window of the inverter is normal, if it is incorrect, it should be reset.
	The difference between voltage inverter and current inverter - LS produces electricity For example, the operating principle of voltage inverter is mainly to regulate the voltage source, and the voltage source regulates the current to achieve the role of conditioning, while the current inverter is to directly regulate the current to achieve the role of conditioning. ...
	Wiring method of the main circuit of the inverter - LS power generation 1. The power supply should be connected to the R, S, and T terminals of the VFD, and should not be connected to the VFD (U, V, W), otherwise the VFD will be damaged. It is necessary to clean up the trivial parts of the wire head after wiring, which may lead to abnormalities, failures, and failures, and it is necessary for the VFD to always be clean. When punching holes in the console, note that ...
	The main functions and functions of LS power production PLC 1. For sequential control: sequential control is based on the current and pre-historical conditions of the input switch, and produces the required switching output, so that the system can work in a certain order. This is the basic manipulation of the system. It is also a common manipulation in discrete production processes. ...
	LS power generation installs the switching power supply step 1. Confirm the location of the device Before the equipment switches on and off the power supply, it is necessary to confirm the location of the equipment, and generally require the equipment to be in a ventilated, boring, non-corrosive gas and dust-free place. 2. Equipment holder The fixed base of the switching power supply is fixed on the orientation of the equipment, and the general ...
	Methods for extending the service life of inverters - LS generates electricity 1. The influence of electromagnetic disturbance on the inverter: In the modern industrial control system, the microcomputer or PLC control technology is mostly selected, and in the process of system planning or transformation, it is necessary to pay attention to the disturbance of the inverter to the microcomputer control board. The inverter is disturbed by the outside world, because the user ...
	An internal component of LS's power circuit breaker 1. Auxiliary contact: the contact mechanically linked with the main circuit of the circuit breaker and the closing mechanism is mainly used for the display of the circuit breaker and the closing status, and is connected to the control circuit of the circuit breaker through the opening and closing of the circuit breaker to control or interlock its related electrical appliances. For example, output to signal lights, relays, etc.
	Introduction to the working principle of LS electric molded case circuit breaker Molded case circuit breakers are also known as equipment circuit breakers, all parts are sealed in plastic housings, auxiliary contacts, undervoltage trippers and shunt trippers are modular. Because of the very compact structure, the molded case circuit breaker is basically impossible to maintain. It is mostly manually operated, and the large capacity ...
	Analysis of the working principle of the inverter - LS power generation The rectified DC voltage of the rectifier contains the pulsating voltage of the power supply 6 times the frequency, and the pulsating current generated by the inverter also changes the DC voltage. The main power is the power replacement part of the power supply for the asynchronous motor voltage regulation and frequency modulation power supply, and the main power of the inverter can be roughly divided into two ...
	Six misunderstandings in the installation and use of inverters - electricity production Myth 1: Connect electromagnetic switches and electromagnetic touches in the output circuit of the inverter In practical application, some occasions need to use the touch device for frequency converter switching: such as switching to the power frequency state when the frequency conversion is faulty, or the election is used to drag two methods, a motor is faulty, and the variable frequency is used.
	Distinguish between good and bad inverters - LS produces electricity The quality of a thing is relatively speaking, the inverter as a power supply used to drive the motor to run, its function is to regulate the speed, under the premise of normal wiring, reasonable parameters, and no fault with the load, if the speed of the motor can be controlled according to the requirements, the shaking error is less than the equipment ...
	Key points of LS power BKN circuit breaker design (1) The cooperation between the circuit breaker and the circuit breaker should consider the instantaneous trip device action value of the superior circuit breaker, which should be greater than the maximum expected short-circuit current at the outlet end of the lower circuit breaker.
	Classification of the nature of DC power supply of inverter - LS power generation A frequency converter is actually an inverter. It starts by turning alternating current into direct current. Then the direct current is switched on and off with electronic components. Becomes alternating current. Thyristors for general inverters with larger power. And set up a device with adjustable frequency. Make the frequency adjustable within a certain range. Used to control ...
	The wiring distance between the motor and the inverter Burn two new motors in a row! The output current and voltage of the inverter are balanced, the input voltage is balanced, the current is unstable, and the fluctuation is 20%-50%, the inverter is burned off by a short circuit between 35Hz turns, the grid voltage is very stable, 720V, the interval between the motor and the inverter is 120m, and the input and output terminals of the inverter are powered ...
	The role of contactors in industrial electricity - LS generates electricity The contactor is an automatic switch in industrial electricity that uses a button to control its on/off. The contactor consists of an electromagnetic coil, a static armature, a moving armature, a static contact, a moving contact and a fixing bracket. The principle is that when the electromagnetic coil of the contactor is connected to the communication electricity, a strong magnetic field will be generated to make the center of the coil ...
	Models and features of LS Metasol series products Metasol series MS (100A and below) products are newly launched and the primary product specifications: contactors, thermal relays, and center relays. Features: The body is small, the internal structure is sealed, and the safety factor is high ...
	Introduction to the use of PLC for power production 1. It is used for switching control The ability of PLC to manipulate switching quantities is very strong. The number of points in and out of the control, less than a dozen points, dozens of points, more can be hundreds, thousands, or even tens of thousands of points, because it can be networked, the number of points is almost unlimited, no matter how many points can be controlled, the control ...
	Elements of LS power inverter operation 1. Physical environment (1) Temperature factor Temperature has a huge impact on the lifetime and reliability of the electronic components inside the inverter. When using the inverter in a high operating temperature environment, it is necessary to take additional cooling measures to ensure that the ambient temperature is stable in the inverter.
	Inverter harmonic suppression method - LS power generation 1. Install an appropriate reactor The input side and the output side of the inverter are connected in series with suitable reactors to absorb harmonics and increase the impedance of the power supply or load, so as to achieve the purpose of pressing harmonics to reduce electromagnetic radiation in the transmission process. After pressing the harmonic current, the power factor is changed from the original ...
	Dealing with intermittent shutdown fault measures - power generation Because the touch of the network adapter is not good, perhaps due to disturbance and other problems, the DP network that has been used for a long time may show a "transient disconnection" situation, that is, it will be disconnected by an occasional moment, and it will soon recover normally. If OB86 is not downloaded, the CPU will stop during a transient outage. Now all over the option to download a ...