阅读说明：本技术 一种变频器的电压或电流校准方法、变频器及系统 (Voltage or current calibration method of frequency converter, frequency converter and system ) 是由 史望龙 李崇波 毛康宇 邹缙 于 2020-12-29 设计创作，主要内容包括：本发明公开了一种变频器的电压或电流校准方法、变频器及系统,涉及变频器控制技术领域,该校准方法包括以下步骤：获取输入或输出变频器的电压或电流的实际有效值,并获取变频器采集的电压或电流的采样有效值；根据实际有效值和采样有效值计算偏差倍数,并根据所述偏差倍数计算变频器的校准采样系数；利用校准采样系数对变频器采集的电压或电流进行校准。本发明通过计算变频器采集的电压或电流的校准采样系数,利用校准采样系数对变频器采集的电压或电流进行校准,校准过程基本不需要人工干预,可快速实现变频器采集的电压或电流的校准。(The invention discloses a voltage or current calibration method of a frequency converter, the frequency converter and a system, and relates to the technical field of frequency converter control, wherein the calibration method comprises the following steps: acquiring an actual effective value of voltage or current input or output to the frequency converter, and acquiring a sampling effective value of the voltage or current acquired by the frequency converter; calculating a deviation multiple according to the actual effective value and the sampling effective value, and calculating a calibration sampling coefficient of the frequency converter according to the deviation multiple; and calibrating the voltage or current collected by the frequency converter by utilizing the calibration sampling coefficient. According to the invention, the calibration sampling coefficient of the voltage or the current collected by the frequency converter is calculated, the voltage or the current collected by the frequency converter is calibrated by using the calibration sampling coefficient, manual intervention is basically not required in the calibration process, and the calibration of the voltage or the current collected by the frequency converter can be quickly realized.)

1. A voltage or current calibration method of a frequency converter is characterized by comprising the following steps:

acquiring an actual effective value of voltage or current input or output to the frequency converter, and acquiring a sampling effective value of the voltage or current acquired by the frequency converter;

calculating a deviation multiple according to the actual effective value and the sampling effective value, and calculating a calibration sampling coefficient of the frequency converter according to the deviation multiple;

and calibrating the voltage or current collected by the frequency converter by utilizing the calibration sampling coefficient.

2. A method of calibrating voltage or current of a frequency converter according to claim 1, wherein said calculating a deviation multiple from the actual effective value and the sampled effective value and calculating a calibrated sampling coefficient of the frequency converter from the deviation multiple comprises:

according to formula K_Deflection＝T_{Fruit of Chinese wolfberry}/T_MiningAnd T_Mining＝K_{First stage}*T_{First stage}Calculating deviation multiple K_Deflection；

Wherein, T_{Fruit of Chinese wolfberry}For inputting or outputting an actual effective value, T, of the voltage or current of the frequency converter_MiningEffective value of voltage or current sampled for a frequency converter, K_{First stage}Is the initial sampling coefficient, T, of the frequency converter_{First stage}Is the initial sampling value of the frequency converter.

3. A method of calibrating voltage or current of a frequency converter according to claim 2, wherein said calculating a deviation multiple from the actual effective value and the sampled effective value and calculating a calibrated sampling coefficient of the frequency converter from the deviation multiple comprises:

according to formula K_School＝K_{First stage}*K_DeflectionCalculating a calibration sampling coefficient K_School。

4. The method for calibrating voltage or current of a frequency converter according to claim 1, wherein before calibrating the voltage or current collected by the frequency converter by using the calibration sampling coefficient, the method comprises:

judging whether the deviation multiple is within 0.8-1.1: if so, adjusting the sampling coefficient of the frequency converter according to the deviation multiple; if not, stopping calibration.

5. The method for calibrating voltage or current of a frequency converter according to claim 1, wherein before obtaining the actual effective value of the voltage or current of the input or output frequency converter and obtaining the sampled effective value of the voltage or current collected by the frequency converter, the method comprises:

the actual effective value of the voltage or current input or output to the frequency converter is measured by a standard meter.

6. A frequency converter with voltage or current calibration, comprising:

the acquisition module is used for acquiring the actual effective value of the voltage or the current of the input or output frequency converter and acquiring the sampling effective value of the voltage or the current collected by the frequency converter;

the calculating module is used for calculating a deviation multiple according to the actual effective value and the sampling effective value and calculating a calibration sampling coefficient of the frequency converter according to the deviation multiple;

and the calibration module is used for calibrating the voltage or the current collected by the frequency converter by utilizing the calibration sampling coefficient.

7. The apparatus for calibrating voltage or current of a frequency converter according to claim 6, wherein:

the calculation module is used for calculating the formula K_Deflection＝T_{Fruit of Chinese wolfberry}/T_MiningAnd T_Mining＝K_{First stage}*T_{First stage}Calculating deviation multiple K_Deflection(ii) a Wherein, T_{Fruit of Chinese wolfberry}Is input orActual effective value of voltage or current, T, of output frequency converter_MiningEffective value of voltage or current sampled for a frequency converter, K_{First stage}Is the initial sampling coefficient, T, of the frequency converter_{First stage}Is the initial sampling value of the frequency converter.

8. The apparatus for calibrating voltage or current of a frequency converter according to claim 7, wherein:

the calculation module is used for calculating the formula K_School＝K_{First stage}*K_DeflectionCalculating a calibration sampling coefficient K_School。

9. The apparatus for calibrating voltage or current of a frequency converter according to claim 6, further comprising:

the judgment module is used for judging whether the deviation multiple is located in 0.8-1.1: if so, the calibration module calibrates the voltage or the current collected by the frequency converter according to the calibration sampling coefficient; if not, the calibration module stops calibration.

10. A voltage or current calibration system for a frequency converter, comprising:

a standard meter for measuring an actual effective value of a voltage or a current input to or output from the frequency converter;

the frequency converter is used for acquiring an actual effective value measured by the standard instrument and acquiring a sampling effective value of voltage or current acquired by the frequency converter; calculating a deviation multiple according to the actual effective value and the sampling effective value, and calculating a calibration sampling coefficient of the frequency converter according to the deviation multiple; and calibrating the voltage or current collected by the frequency converter by utilizing the calibration sampling coefficient.

Technical Field

The invention relates to the technical field of frequency converter control, in particular to a voltage or current calibration method of a frequency converter, the frequency converter and a system.

Background

Currently, in the control of a high-voltage inverter, the voltage or current of an input or output inverter needs to be sampled in real time for control, such as overvoltage and overcurrent protection. Due to the influence of external factors (temperature, humidity and the like), parameters of some analog devices such as a part of resistance-capacitance operational amplifier of a sampling circuit of the frequency converter can be changed, and the value of a sampling coefficient is uncertain under the influence of the external factors at different temperatures, so that certain deviation occurs in a voltage or current sampling instantaneous value, the control of the frequency converter is deviated and even wrong, and the hazards of overvoltage and overcurrent protection, malfunction, shutdown and the like occur.

In the prior art, the adjustment is performed by artificially changing the sampling coefficient. However, this method usually requires manual adjustment for many times to find the correct sampling coefficient, which is time-consuming and requires skilled personnel to operate, which is very inconvenient, and if the setting is incorrect, this may result in disadvantages such as trip.

Disclosure of Invention

The embodiment of the invention provides a voltage or current calibration method of a frequency converter, the frequency converter and a system, and aims to solve the technical problems that in the related art, the sampling coefficient of the frequency converter needs to be adjusted manually for multiple times, the time consumption is long, and the technical requirements on personnel are high.

In a first aspect, a voltage or current calibration method for a frequency converter is provided, which includes the following steps:

acquiring an actual effective value of voltage or current input or output to the frequency converter, and acquiring a sampling effective value of the voltage or current acquired by the frequency converter;

calculating a deviation multiple according to the actual effective value and the sampling effective value, and calculating a calibration sampling coefficient of the frequency converter according to the deviation multiple;

and calibrating the voltage or current collected by the frequency converter by utilizing the calibration sampling coefficient.

In some embodiments, the calculating a deviation multiple according to the actual effective value and the sampling effective value, and calculating a calibration sampling coefficient of the frequency converter according to the deviation multiple includes:

according to formula K_Deflection＝T_{Fruit of Chinese wolfberry}/T_MiningAnd T_Mining＝K_{First stage}*T_{First stage}Calculating deviation multiple K_Deflection；

Wherein，T_{Fruit of Chinese wolfberry}For inputting or outputting an actual effective value, T, of the voltage or current of the frequency converter_MiningEffective value of voltage or current sampled for a frequency converter, K_{First stage}Is the initial sampling coefficient, T, of the frequency converter_{First stage}Is the initial sampling value of the frequency converter.

In some embodiments, the calculating a deviation multiple according to the actual effective value and the sampling effective value, and calculating a calibration sampling coefficient of the frequency converter according to the deviation multiple includes:

according to formula K_School＝K_{First stage}*K_DeflectionCalculating a calibration sampling coefficient K_School。

In some embodiments, before calibrating the voltage or current collected by the frequency converter by using the calibration sampling coefficient, the method includes:

judging whether the deviation multiple is within 0.8-1.1: if so, adjusting the sampling coefficient of the frequency converter according to the deviation multiple; if not, stopping calibration.

In some embodiments, before obtaining the actual effective value of the voltage or the current input to or output from the frequency converter and obtaining the sampled effective value of the voltage or the current collected by the frequency converter, the method includes:

the actual effective value of the voltage or current input or output to the frequency converter is measured by a standard meter.

In a second aspect, there is provided a frequency converter with voltage or current calibration function, comprising:

the acquisition module is used for acquiring the actual effective value of the voltage or the current of the input or output frequency converter and acquiring the sampling effective value of the voltage or the current collected by the frequency converter;

the calculating module is used for calculating a deviation multiple according to the actual effective value and the sampling effective value and calculating a calibration sampling coefficient of the frequency converter according to the deviation multiple;

and the calibration module is used for calibrating the voltage or the current collected by the frequency converter by utilizing the calibration sampling coefficient.

In some embodiments, the calculation module is configured to calculate the value according to formula K_Deflection＝T_{Fruit of Chinese wolfberry}/T_MiningAnd T_Mining＝K_{First stage}*T_{First stage}Calculating deviation multiple K_Deflection(ii) a Wherein, T_{Fruit of Chinese wolfberry}For inputting or outputting an actual effective value, T, of the voltage or current of the frequency converter_MiningEffective value of voltage or current sampled for a frequency converter, K_{First stage}Is the initial sampling coefficient, T, of the frequency converter_{First stage}Is the initial sampling value of the frequency converter.

In some embodiments, the calculation module is configured to calculate the value according to formula K_School＝K_{First stage}*K_DeflectionCalculating a calibration sampling coefficient K_School。

In some embodiments, the frequency converter further comprises:

the judgment module is used for judging whether the deviation multiple is located in 0.8-1.1: if so, the calibration module calibrates the voltage or the current collected by the frequency converter according to the calibration sampling coefficient; if not, the calibration module stops calibration.

In a third aspect, a voltage or current calibration system for a frequency converter is provided, comprising:

a standard meter for measuring an actual effective value of a voltage or a current input to or output from the frequency converter;

the frequency converter is used for acquiring an actual effective value measured by the standard instrument and acquiring a sampling effective value of voltage or current acquired by the frequency converter; calculating a deviation multiple according to the actual effective value and the sampling effective value, and calculating a calibration sampling coefficient of the frequency converter according to the deviation multiple; and calibrating the voltage or current collected by the frequency converter by utilizing the calibration sampling coefficient.

The technical scheme provided by the invention has the beneficial effects that:

the embodiment of the invention provides a voltage or current calibration method of a frequency converter, the frequency converter and a system, wherein the frequency converter calculates a deviation multiple according to an actual effective value of voltage or current of an input or output frequency converter and a sampling effective value of voltage or current acquired by the frequency converter, calculates a calibration sampling coefficient of the frequency converter according to the actual effective value and the sampling effective value, ensures that the calibration sampling coefficient meets the calibration requirement, and finally realizes the voltage or current calibration of the frequency converter by using the calibration sampling coefficient.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.

Fig. 1 is a schematic flowchart of a voltage or current calibration method for a frequency converter according to an embodiment of the present invention;

fig. 2 is a schematic diagram of a frequency converter with a voltage or current calibration function according to an embodiment of the present invention;

fig. 3 is a schematic diagram of a frequency converter of a voltage or current calibration system of the frequency converter according to an embodiment of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, are within the scope of the present invention.

The embodiment of the invention provides a voltage or current calibration method of a frequency converter, which can solve the technical problems that in the prior art, the sampling coefficient of the frequency converter needs to be manually adjusted for many times, the time consumption is long, and the technical requirement on personnel is high.

Referring to fig. 1, a voltage or current calibration method for a frequency converter includes the following steps:

101. and acquiring an actual effective value of the voltage or current input or output to the frequency converter, and acquiring a sampling effective value of the voltage or current collected by the frequency converter.

102. And calculating a deviation multiple according to the actual effective value and the sampling effective value, and calculating a calibration sampling coefficient of the frequency converter according to the deviation multiple.

In particular, according to formula K_Deflection＝T_{Fruit of Chinese wolfberry}/T_MiningAnd T_Mining＝K_{First stage}*T_{First stage}Calculating deviation multiple K_Deflection. Wherein, T_{Fruit of Chinese wolfberry}For inputting or outputting an actual effective value, T, of the voltage or current of the frequency converter_MiningEffective value of voltage or current sampled for a frequency converter, K_{First stage}Is the initial sampling coefficient, T, of the frequency converter_{First stage}Is the initial sampling value of the frequency converter. Further, according to formula K_School＝K_{First stage}*K_DeflectionCalculating a calibration sampling coefficient K_School。

103. And calibrating the voltage or current collected by the frequency converter by utilizing the calibration sampling coefficient.

The following description is made with respect to calibration of the input voltage:

before calibration, the effective sampling value of the voltage collected by the frequency converter is assumed to be T_Mining＝K_{First stage}*T_{First stage}9.7KV and the actual effective value of the voltage currently input to the frequency converter is T_{Fruit of Chinese wolfberry}10 KV. According to formula K_Deflection＝T_{Fruit of Chinese wolfberry}/T_MiningCalculating deviation multiple K_Deflection10/9.7-1.031. According to formula K_School＝K_{First stage}*K_DeflectionCalculating a calibration sampling coefficient K_School＝1.031K_{First stage}。

After calibration, the effective sampling value of the voltage collected by the frequency converter is T_Mining’＝K_School*T_{First stage}＝K_{First stage}*K_Deflection*T_{First stage}＝10KV，T_Mining' has an actual effective value of T_{Fruit of Chinese wolfberry}The term "equal" means that the sampled effective value of the voltage sampled by the frequency converter is accurate, and the sampled effective value of the voltage sampled by the frequency converter is obtained based on the sampled instantaneous value at each moment, so that the sampled instantaneous value of the voltage sampled by the frequency converter is also accurate.

Therefore, in the voltage or current calibration method for the frequency converter in the embodiment of the invention, the actual effective value and the sampling effective value of the voltage or current input or output to the frequency converter are obtained, the deviation multiple is calculated according to the actual effective value and the sampling effective value, the calibration sampling coefficient of the frequency converter is calculated according to the deviation multiple, the calibration sampling coefficient is ensured to meet the calibration requirement, finally, the voltage or current collected by the frequency converter is calibrated by utilizing the calibration sampling coefficient, the calibration process basically does not need manual intervention, and the calibration of the voltage or current collected by the frequency converter can be quickly realized.

As an optional implementation manner, before calibrating the voltage or current collected by the frequency converter by using the calibration sampling coefficient, judging whether the deviation multiple is within 0.8-1.1: if so, adjusting the sampling coefficient of the frequency converter according to the deviation multiple; if not, stopping adjusting the sampling coefficient of the frequency converter. The sampling coefficient deviation caused by external factors is generally small, only fine adjustment calibration needs to be carried out on the sampling coefficient, and the deviation multiple is generally caused by device faults. The embodiment of the invention judges whether the deviation multiple is within 0.8-1.1, and can prevent the calibration of larger deviation caused by device failure, thereby preventing the device failure from being calibrated to be failure-free and ensuring the equipment safety.

As an optional implementation manner, the actual effective value of the voltage or the current of the input or output frequency converter is obtained, and before the sampling effective value of the voltage or the current collected by the frequency converter is obtained, the actual effective value of the voltage or the current of the input or output frequency converter is measured by the standard instrument, so that the measurement precision of the standard instrument is high, and the standard instrument can be used as a reference for calculating deviation multiples, and the final calibration effect is improved.

Referring to fig. 2, an embodiment of the present invention further provides a frequency converter with a voltage or current calibration function, including: the device comprises an acquisition module, a calculation module and a calibration module.

The acquisition module is used for acquiring the actual effective value of the voltage or the current of the input or output frequency converter and acquiring the sampling effective value of the voltage or the current collected by the frequency converter.

The calculating module is used for calculating the deviation multiple according to the actual effective value and the sampling effective value and calculating the calibration sampling coefficient of the frequency converter according to the deviation multiple.

In particular, the calculation module is configured to calculate the value of the equation K according to the formula_Deflection＝T_{Fruit of Chinese wolfberry}/T_MiningAnd T_Mining＝K_{First stage}*T_{First stage}Calculating deviation multiple K_Deflection(ii) a Wherein, T_{Fruit of Chinese wolfberry}For inputting or outputting an actual effective value, T, of the voltage or current of the frequency converter_MiningEffective value of voltage or current sampled for a frequency converter, K_{First stage}Is the initial sampling coefficient, T, of the frequency converter_{First stage}Is the initial sampling value of the frequency converter. Further, the calculation module is used for calculating the formula K_School＝K_{First stage}*K_DeflectionCalculating a calibration sampling coefficient K_School。

The calibration module is used for calibrating the voltage or the current collected by the frequency converter by utilizing the calibration sampling coefficient.

As an optional implementation manner, the frequency converter with the voltage or current calibration function in the embodiment of the present invention further includes a determining module, where the determining module is configured to determine whether the deviation multiple is within 0.8-1.1: if so, adjusting the sampling coefficient of the frequency converter according to the deviation multiple; if not, stopping adjusting the sampling coefficient of the frequency converter. The sampling coefficient deviation caused by external factors is generally small, only fine adjustment calibration needs to be carried out on the sampling coefficient, and the deviation multiple is generally caused by device faults. The embodiment of the invention judges whether the deviation multiple is within 0.8-1.1, and can prevent the calibration of larger deviation caused by device failure, thereby preventing the device failure from being calibrated to be failure-free and ensuring the equipment safety.

Referring to fig. 3, an embodiment of the present invention further provides a voltage or current calibration system for a frequency converter, including: standard instruments and frequency converters.

The standard meter is used for measuring the actual effective value of the voltage or the current of the input or output frequency converter.

The frequency converter is used for acquiring an actual effective value measured by the standard instrument and acquiring a sampling effective value of voltage or current acquired by the frequency converter; calculating a deviation multiple according to the actual effective value and the sampling effective value, and calculating a calibration sampling coefficient of the frequency converter according to the deviation multiple; and calibrating the voltage or current collected by the frequency converter by utilizing the calibration sampling coefficient.

In the description of the present invention, it should be noted that the terms "upper", "lower", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, which are merely for convenience in describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed in a specific orientation, and operate, and thus, should not be construed as limiting the present invention. Unless expressly stated or limited otherwise, the terms "mounted," "connected," and "connected" are intended to be inclusive and mean, for example, that they may be fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

It is to be noted that, in the present invention, relational terms such as "first" and "second", and the like, are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.

The foregoing are merely exemplary embodiments of the present invention, which enable those skilled in the art to understand or practice the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.