CN220527885U - Frequency converter - Google Patents
Frequency converter Download PDFInfo
- Publication number
- CN220527885U CN220527885U CN202321054922.1U CN202321054922U CN220527885U CN 220527885 U CN220527885 U CN 220527885U CN 202321054922 U CN202321054922 U CN 202321054922U CN 220527885 U CN220527885 U CN 220527885U
- Authority
- CN
- China
- Prior art keywords
- frequency converter
- electric energy
- energy metering
- main control
- control chip
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 238000000034 method Methods 0.000 claims abstract description 10
- 238000005070 sampling Methods 0.000 claims description 68
- 238000012544 monitoring process Methods 0.000 abstract description 8
- 230000000694 effects Effects 0.000 abstract description 3
- 238000004364 calculation method Methods 0.000 description 14
- 239000003990 capacitor Substances 0.000 description 14
- 238000010586 diagram Methods 0.000 description 3
- 238000005265 energy consumption Methods 0.000 description 3
- 230000003993 interaction Effects 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 3
- 238000005259 measurement Methods 0.000 description 2
- 238000012800 visualization Methods 0.000 description 2
- 230000005540 biological transmission Effects 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 230000008094 contradictory effect Effects 0.000 description 1
- 230000005611 electricity Effects 0.000 description 1
- 238000000605 extraction Methods 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- 238000005272 metallurgy Methods 0.000 description 1
- -1 metallurgy Substances 0.000 description 1
- 230000002093 peripheral effect Effects 0.000 description 1
- 230000002265 prevention Effects 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 239000004753 textile Substances 0.000 description 1
Landscapes
- Supply And Distribution Of Alternating Current (AREA)
Abstract
The utility model discloses a frequency converter, and belongs to the technical field of frequency converters. The frequency converter comprises a frequency converter main control chip, wherein the frequency converter main control chip is electrically connected with an electric energy metering card, the input end of the electric energy metering card is connected to the power grid side, and the frequency converter main control chip receives and displays electric energy metering parameters output by the electric energy metering card. According to the utility model, the main control chip of the frequency converter does not execute the metering process of the input electric energy, the electric energy metering card meters the electric energy input to the frequency converter at the power grid side, the main control chip of the frequency converter directly reads the electric energy metering parameters from the electric energy metering card, the normal motor control algorithm execution of the frequency converter is not influenced, the additional main control chip is not needed, the cost of the electric energy meter is far lower, the equivalent metering effect of the electric energy meter is realized, and the cost of the frequency converter required in the process of equipment-level energy monitoring is further reduced.
Description
Technical Field
The utility model relates to the technical field of frequency converters, in particular to a frequency converter.
Background
The frequency converter is widely applied to various manufacturing occasions such as elevators, textiles, metallurgy, chemical industry and the like. In various manufacturing occasions, the frequency converter reconstructs the running state of the motor through output side voltage and current sampling, and further, the rotating speed and the torque of the motor are accurately controlled. However, in the above process, only the output energy of the frequency converter is calculated, but the energy consumption of the frequency converter is ignored, and the parameters which can be calculated are limited, that is, the frequency converter is difficult to meet the equipment-level energy (energy consumption of each equipment) monitoring requirement.
At present, aiming at the problem that the frequency converters are difficult to meet the equipment-level energy monitoring requirement, one of the solutions is to input an externally-hung ammeter for each frequency converter, but the scheme has huge cost and cannot be popularized on a large scale.
Disclosure of Invention
The main purpose of the utility model is to provide a frequency converter, which aims at reducing the cost required by the frequency converter in the process of equipment-level energy monitoring.
In order to achieve the above purpose, the frequency converter provided by the utility model comprises a frequency converter main control chip, wherein the frequency converter main control chip is electrically connected with an electric energy metering card, the input end of the electric energy metering card is connected to the power grid side, and the frequency converter main control chip receives and displays electric energy metering parameters output by the electric energy metering card.
Optionally, the electric energy metering card is integrated on a frequency converter control board where the frequency converter main control chip is located.
Optionally, the electric energy metering card is integrated on a PCB board, and the PCB board and a frequency converter control board where the frequency converter main control chip is located are mutually independent.
Optionally, the electric energy metering card includes sampling circuit and electric energy metering chip, sampling circuit's input access electric wire netting side, sampling circuit's output with electric energy metering chip's input electric connection, electric energy metering chip's output with converter main control chip's input electric connection, wherein:
the sampling circuit collects sampling current and sampling voltage at the power grid side and transmits the sampling current and the sampling voltage to the electric energy metering chip;
the electric energy metering chip receives the sampling current and the sampling voltage and outputs electric energy metering parameters to the main control chip of the frequency converter.
Optionally, the electric energy metering chip is electrically connected with the main control chip of the frequency converter through an SPI interface.
Optionally, the sampling circuit adopts a resistor voltage division mode to sample voltage, and adopts a transformer differential input mode to sample current.
Optionally, the electric energy metering card and the main control chip of the frequency converter are used for transmitting the calibration parameters.
Optionally, the electric energy metering card is electrically connected with a power supply of the frequency converter.
Optionally, the electric energy metering card is electrically connected with the main control chip of the frequency converter through a flat cable.
According to the technical scheme, the electric energy metering parameters input to the frequency converter at the power grid side are obtained through the electric energy metering card, and the frequency converter main control chip receives and displays the electric energy metering parameters output by the electric energy metering card. That is, the main control chip of the frequency converter does not execute the metering process of the input electric energy, the electric energy metering card meters the electric energy input to the frequency converter at the power grid side, the main control chip of the frequency converter directly reads the electric energy metering parameters from the electric energy metering card, the normal motor control algorithm of the frequency converter is not affected, the extra main control chip is not needed, the cost far lower than that of the electric energy meter is used, the metering effect equivalent to the electric energy meter is realized, and the cost required by the frequency converter in the process of equipment-level energy monitoring is further reduced.
Drawings
In order to more clearly illustrate the embodiments of the present utility model or the technical solutions in the prior art, the drawings that are required in the embodiments or the description of the prior art will be briefly described, and it is obvious that the drawings in the following description are only some embodiments of the present utility model, and other drawings may be obtained according to the structures shown in these drawings without inventive effort for a person skilled in the art.
FIG. 1 is a schematic diagram of a first embodiment of a transducer energy visualization system according to the present utility model;
fig. 2 is a schematic circuit diagram of a sampling circuit according to the present utility model.
The achievement of the objects, functional features and advantages of the present utility model will be further described with reference to the accompanying drawings, in conjunction with the embodiments.
Detailed Description
The following description of the embodiments of the present utility model will be made clearly and fully with reference to the accompanying drawings, in which it is evident that the embodiments described are only some, but not all embodiments of the utility model. All other embodiments, which can be made by those skilled in the art based on the embodiments of the utility model without making any inventive effort, are intended to be within the scope of the utility model.
It should be noted that all directional indicators (such as up, down, left, right, front, and rear … …) in the embodiments of the present utility model are merely used to explain the relative positional relationship, movement, etc. between the components in a particular posture (as shown in the drawings), and if the particular posture is changed, the directional indicator is changed accordingly.
In the present utility model, unless specifically stated and limited otherwise, the terms "connected," "affixed," and the like are to be construed broadly, and for example, "affixed" may be a fixed connection, a removable connection, or an integral body; can be mechanically or electrically connected; either directly or indirectly, through intermediaries, or both, may be in communication with each other or in interaction with each other, unless expressly defined otherwise. The specific meaning of the above terms in the present utility model can be understood by those of ordinary skill in the art according to the specific circumstances.
Furthermore, descriptions such as those referred to as "first," "second," and the like, are provided for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implying an order of magnitude of the indicated technical features in the present disclosure. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include at least one such feature. In addition, the meaning of "and/or" as it appears throughout is meant to include three side-by-side schemes, for example, "a and/or B", including a scheme, or B scheme, or a scheme that is satisfied by both a and B. In addition, the technical solutions of the embodiments may be combined with each other, but it is necessary to base that the technical solutions can be realized by those skilled in the art, and when the technical solutions are contradictory or cannot be realized, the combination of the technical solutions should be considered to be absent and not within the scope of protection claimed in the present utility model.
Fig. 1 is a schematic structural diagram of a first embodiment of a frequency converter according to the present utility model. The frequency converter in this embodiment may include a frequency converter main control chip, and the frequency converter main control chip is electrically connected with the electric energy metering card. Wherein: the input end of the electric energy metering card is connected to the power grid side, and the main control chip of the frequency converter receives and displays the electric energy metering parameters output by the electric energy metering card.
The frequency converter provided by the embodiment obtains the electric energy metering parameters input to the frequency converter at the power grid side through the electric energy metering card, and the main control chip of the frequency converter receives and displays the electric energy metering parameters output by the electric energy metering card. That is, the main control chip of the frequency converter does not execute the metering process of the input electric energy, the electric energy metering card meters the electric energy input to the frequency converter at the power grid side, the main control chip of the frequency converter directly reads the electric energy metering parameters from the electric energy metering card, the normal motor control algorithm of the frequency converter is not affected, the extra main control chip is not needed, the cost far lower than that of the electric energy meter is used, the metering effect equivalent to the electric energy meter is realized, and the cost required by the frequency converter in the process of equipment-level energy monitoring is further reduced.
It should be noted that, in this embodiment, the electric energy metering card is disposed at the power grid side, that is, the input side of the frequency converter, the input voltage at the power grid side is collected as the sampling voltage, the input current at the power grid side is collected as the sampling current, and the electric energy calculation is performed based on the sampling voltage and the sampling current, so that the energy consumption of the load side (the motor side) and the frequency converter itself is accurately calculated, the accurate energy monitoring of the whole equipment of the frequency converter-load (the motor) is realized, and further, the energy monitoring and the energy saving management of the whole workshop or even the factory are facilitated, and further, the green intelligent manufacturing is realized.
In one embodiment, the input current at the power grid side of the frequency converter is a non-sinusoidal current, and the power calculation method of the non-sinusoidal circuit can be adopted for electric energy calculation. The power calculation method of the non-sinusoidal circuit comprises the following steps:
the Fourier series form of the port voltage and the port current is set as follows:
wherein ω is the angular frequency corresponding to the fundamental frequency, U 0 And I 0 The direct current components, U, of the voltage and current waveforms, respectively n And I n Effective values of nth harmonic components of voltage and current waveforms, alpha n And beta n The primary phases of the nth harmonic component of the voltage and current waveforms, respectively.
The effective values of the voltage and the current are as follows:
wherein U is a voltage effective value, I is a current effective value, U n And I n The effective values of the nth frequency multiplication harmonic components of the voltage and current waveforms respectively;
the apparent power is calculated as:
S＝UI；
wherein S is apparent power, U is voltage effective value, I is current effective value;
the calculation formula of the active power is as follows:
wherein P is active power, T is sampling period, U (T) is Fourier series form of port voltage, i (T) is Fourier series form of port current, U 0 And I 0 Voltage and current respectivelyThe DC component of the waveform, U n And I n Effective values of nth harmonic components of voltage and current waveforms, respectively, θ n Is U (U) n And I n Phase difference, P 0 Is the direct current active power, P 1 Is the fundamental wave active power, P n Is harmonic active power;
the calculation formula of the reactive power is as follows:
wherein Q is reactive power, U n And I n Effective values of nth harmonic components of voltage and current waveforms, respectively, θ n Is U (U) n And I n Is a phase difference of (2);
it should be noted that, the relation of power triangle is not satisfied between the active power, the reactive power and the apparent power, that is, the apparent power includes the active power and the inactive power, but the inactive power is not equal to the reactive power, for this purpose, the distortion power D needs to be defined:
S 2 ＝P 2 +Q 2 +D 2 。
it should be noted that, after sampling the voltage and current at the grid side, the electric energy metering card can implement energy calculation based on the power calculation method of the non-sinusoidal circuit.
In some embodiments, the electric energy metering card includes sampling circuit and electric energy metering chip, and sampling circuit's input inserts the electric wire netting side, sampling circuit's output and electric energy metering chip's input electric connection, electric energy metering chip's output and converter main control chip's input electric connection, wherein: the sampling circuit collects sampling current and sampling voltage at the power grid side and transmits the sampling current and the sampling voltage to the electric energy metering chip; the electric energy metering chip receives the sampling current and the sampling voltage and outputs electric energy metering parameters to the main control chip of the frequency converter.
It should be noted that, as shown in fig. 1, the sampling circuit is electrically connected with the power grid through an input terminal, and is used for obtaining a sampling current and a sampling voltage at the power grid side; the output end of the sampling circuit is electrically connected with the input end of the electric energy metering chip, and the sampling current and the sampling voltage are respectively sent to the electric energy metering chip in the form of current sampling signal voltage sampling signals; the output end of the electric energy metering chip is electrically connected with the input end of the frequency converter main control chip, so that signal interaction between the electric energy metering chip and the frequency converter main control chip is realized, namely, the frequency converter main control chip reads the calculation result of electric energy calculation from the electric energy metering chip. The main control chip of the frequency converter is arranged in the main control board in fig. 1, and is not explicitly marked in fig. 1.
In this embodiment, the output end of the electric energy metering chip and the input end of the main control chip of the frequency converter may be electrically connected through an SPI (serial peripheral interface ) interface.
In some embodiments, the power metering card is integrated on a frequency converter control board where the frequency converter main control chip is located.
In some embodiments, the electric energy metering card is integrated on a PCB board, which is set independently of a frequency converter control board where the frequency converter main control chip is located, as shown in fig. 1.
It should be noted that, the electric energy metering card is integrated on the frequency converter control board where the frequency converter main control chip is located, or is integrated on the PCB board which is mutually independent with the frequency converter control board where the frequency converter main control chip is located, and specifically can be determined according to actual conditions, which is not limited in this embodiment of the present specification.
When the electric energy metering card is integrated on a PCB board card which is mutually independent with a frequency converter control board where the frequency converter main control chip is located, as shown in fig. 1, the electric energy metering card is electrically connected with the frequency converter main control chip through a flat cable, the sampling circuit is connected with a frequency converter main circuit through an output terminal, and the frequency converter main circuit is connected with a load motor. It can be understood that the electric energy metering card is connected with the main control chip of the frequency converter through a flat cable to realize data interaction and power supply, and is connected with the main circuit of the frequency converter through an external wiring mode, namely, the electric energy metering card and the main control chip of the frequency converter can quickly and conveniently form an energy visualization system.
In some embodiments, the power metering card is electrically connected to a power supply of the frequency converter. That is, the power required for operation of the power metering card is provided by the frequency converter.
In some embodiments, the transmission of the calibration parameters is performed between the electric energy metering card and the main control chip of the frequency converter. The meter calibrating parameters are used for calibrating the electric energy metering card, so that the accuracy of electric energy metering of the electric energy metering card is improved.
In some embodiments, the frequency converter main control chip is further configured to send a control instruction to the electric energy metering card, where the control instruction includes a full wave electric energy metering mode or a fundamental wave active electric energy metering mode; the electric energy metering card is also used for calculating electric energy based on the sampling current and the sampling voltage by adopting a full-wave electric energy metering mode or a fundamental wave active electric energy measuring mode to obtain a calculation result.
The full-wave electric energy metering mode comprises the following steps:
taking a multifunctional three-phase electric energy special-purpose electric energy metering chip ATT7022C as an example, seven paths of second-order sigma-delta ADC are integrated in the multifunctional three-phase electric energy special-purpose electric energy metering chip ATT7022C, wherein three paths of the multifunctional three-phase electric energy special-purpose electric energy metering chip are used for three-phase voltage sampling, three paths of the multifunctional three-phase electric energy special-purpose electric energy metering chip are used for three-phase current sampling, and the multifunctional three-phase electric energy special-purpose electric energy metering chip is used for zero line current or sampling of other electricity larceny prevention parameters. Assuming that the sampling period is T and the sampling times in the period is N, the following physical quantity can be calculated:
the active power calculation formula is as follows:
wherein P is active power, N is sampling times in a period, U (t k ) For the value of the sampled voltage of each sampling in the period after the DC component is removed, I (t k ) The dc component of the sampled current is removed for each sample in the cycle.
It can be understood that the active power of each phase in the electric energy metering chip is obtained by performing a series of digital signal processing such as multiplication, addition, digital filtering and the like on the current and voltage signals after the direct current components are removed. The voltage and current sampling data contain up to 41 times of harmonic information, so that the active power calculated according to the formula also contains at least 41 times of harmonic information.
The total active power is the sum of the active powers of the phases.
The reactive power calculation formula is as follows:
wherein Q is reactive power, U n Is the effective value of the nth frequency multiplication harmonic component of the voltage waveform, I n Is the effective value of the nth frequency multiplication harmonic component of the current waveform, theta n Is U (U) n And I n Is a phase difference of (a) and (b).
It should be noted that, the measurement bandwidth of the reactive power of the ATT7022C of the electric energy metering chip can be up to 41 th harmonic.
The apparent power calculation formula is as follows:
wherein Q is reactive power and P is active power.
S＝U rms I rms ；
Wherein U is rms Is the effective value of the voltage, I rms Is the effective value of the current.
The fundamental wave active electric energy measuring mode attenuates harmonic signals higher than 3 times (150 Hz) through a fundamental wave extraction filter, only fundamental wave components are reserved, and therefore fundamental wave components in voltage and current signals are separated, and accurate fundamental wave active power and fundamental wave active electric energy measurement are provided.
In one embodiment, the sampling circuit adopts a resistor voltage division mode to sample voltage, and adopts a mutual inductor differential input mode to sample current.
In this embodiment, the sampling circuit includes a voltage sampling circuit and a current sampling circuit.
As shown in fig. 2 (a), the voltage sampling circuit includes a resistor R101, a resistor R102, a resistor R103, a capacitor C11, and a capacitor C12. One end of the resistor R101 is connected with the positive input end, the other end of the resistor R101 is electrically connected with one end of the resistor R102 and one end of the capacitor C11, one end of the capacitor C11 is connected with the positive output end, the other end of the resistor R102 is electrically connected with one end of the resistor R103, the other end of the capacitor C11 is electrically connected with one end of the capacitor C12 and grounded, the other end of the resistor R103 is connected with the negative input end, the other end of the resistor R103 is electrically connected with the other end of the capacitor C12, and the other end of the capacitor C12 is connected with the negative output end.
As shown in fig. 2 (b), the current sampling circuit includes a resistor R1, a resistor R2, a resistor R3, a resistor R4, a capacitor C1, and a capacitor C2. One end of the resistor R1 is electrically connected with one end of the resistor R2 and is connected with the first input end, the other end of the resistor R1 is electrically connected with one end of the resistor R3 and is connected with the reference signal output end, the other end of the resistor R3 is electrically connected with one end of the resistor R4 and is connected with the second input end, the other end of the resistor R2 is electrically connected with one end of the capacitor C1 and is connected with the first output end, the other end of the resistor R4 is electrically connected with one end of the capacitor C2 and is connected with the second output end, and the other end of the capacitor C1 is electrically connected with the other end of the capacitor C2.
The foregoing description is only of the preferred embodiments of the present utility model and is not intended to limit the scope of the utility model, and all equivalent structural changes made by the description of the present utility model and the accompanying drawings or direct/indirect application in other related technical fields are included in the scope of the utility model.
Claims (9)
1. The frequency converter is characterized by comprising a frequency converter main control chip, wherein the frequency converter main control chip is electrically connected with an electric energy metering card, the input end of the electric energy metering card is connected to the power grid side, and the frequency converter main control chip receives and displays electric energy metering parameters output by the electric energy metering card.
2. The frequency converter according to claim 1, wherein the electric energy metering card is integrated on a frequency converter control board where the frequency converter main control chip is located.
3. The frequency converter according to claim 1, wherein the electric energy metering card is integrated on a PCB card, and the PCB card and a frequency converter control board where the frequency converter main control chip is located are set independently of each other.
4. The frequency converter according to claim 1 or 2, wherein the electric energy metering card comprises a sampling circuit and an electric energy metering chip, an input end of the sampling circuit is connected to a power grid side, an output end of the sampling circuit is electrically connected to an input end of the electric energy metering chip, and an output end of the electric energy metering chip is electrically connected to an input end of the frequency converter main control chip, wherein:
the sampling circuit collects sampling current and sampling voltage at the power grid side and transmits the sampling current and the sampling voltage to the electric energy metering chip;
the electric energy metering chip receives the sampling current and the sampling voltage and outputs electric energy metering parameters to the main control chip of the frequency converter.
5. The transducer of claim 4, wherein the power metering chip is electrically connected to the transducer main control chip via an SPI interface.
6. The frequency converter of claim 4, wherein the sampling circuit performs voltage sampling by using a resistor voltage division method, and the sampling circuit performs current sampling by using a transformer differential input method.
7. The frequency converter according to claim 1, wherein the power metering card and the frequency converter main control chip are used for transmitting meter calibration parameters.
8. The frequency converter of claim 1, wherein the power metering card is electrically connected to a power supply of the frequency converter.
9. The transducer of claim 1, wherein the power metering card is electrically connected to the transducer main control chip by a bus.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202321054922.1U CN220527885U (en) | 2023-05-05 | 2023-05-05 | Frequency converter |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202321054922.1U CN220527885U (en) | 2023-05-05 | 2023-05-05 | Frequency converter |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN220527885U true CN220527885U (en) | 2024-02-23 |
Family
ID=89937045
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202321054922.1U Active CN220527885U (en) | 2023-05-05 | 2023-05-05 | Frequency converter |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN220527885U (en) |
-
2023
- 2023-05-05 CN CN202321054922.1U patent/CN220527885U/en active Active
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN107643447B (en) | Vehicle insulation detection circuit and method | |
| CN108445870B (en) | Insulation monitoring circuit of motor controller | |
| CN110171319B (en) | Three-phase standard alternating-current charging pile capable of being used for tracing | |
| CN203365535U (en) | Vehicle current collection system and car having same | |
| CN220527885U (en) | Frequency converter | |
| CN108414838A (en) | A kind of inverter parallel system line impedance measurement method | |
| CN205160467U (en) | A environmental parameter gather box for photovoltaic power generation system monitoring devices | |
| CN114019242A (en) | Method and device for detecting insulation impedance of direct current side of photovoltaic inverter | |
| CN211928021U (en) | Three-phase electric energy data acquisition circuit of transformer parameter measurement device | |
| CN103543317A (en) | Method for measuring IEC (International Electrical Commission) standard voltage flicker | |
| CN104569675A (en) | Flickering detecting circuit and detecting method in electric energy measuring chip | |
| CN104345218A (en) | Reactance value measurement system and method for three-phase reactor | |
| CN203364846U (en) | A signal conditioning apparatus | |
| CN217543237U (en) | Power consumption metering circuit and charging metering system | |
| CN205160469U (en) | A monitor cell for photovoltaic power generation system monitoring devices | |
| CN214150961U (en) | Hardware circuit of control system of circuit breaker motion characteristic detection device | |
| CN207611099U (en) | A kind of transducer testing system | |
| CN203909130U (en) | High precision multipath AC current true virtual value detection circuit | |
| CN109030943B (en) | ATT 7022C-based voltage harmonic continuous measurement method | |
| CN2695979Y (en) | Three-pincers graphic phase voltammeter | |
| CN104977465A (en) | Remote electric parameter measurement system | |
| CN111220837A (en) | Output voltage detector of broadband PWM frequency converter | |
| CN216209499U (en) | System for detecting three-phase output voltage and current performance state of frequency converter | |
| CN218068139U (en) | Power grid frequency detection circuit and device | |
| CN206132849U (en) | Wide range electric energy metering device |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant |