TWI447400B - Inrush current measuring device - Google Patents
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本發明是有關於一種電流量測裝置。特別是有關於一種湧入電流量測裝置，用來量測馬達或機電設備的能源供應系統之湧入電流。The invention relates to a current measuring device. In particular, there is an inrush current measuring device for measuring the inrush current of an energy supply system of a motor or electromechanical device.
湧入電流指的是當一電子設備剛開啟電源時，最高、瞬間輸入的電流值。它常見於馬達或機電設備的能源供應系統。當該馬達或機電設備開啟時，一大電流會瞬時地產生。有時，該湧入電流能比穩態電流高上5至10倍，而該穩態電流僅短暫出現於該馬達或機電設備暖機後。能源供應系統的電壓值隨著湧入電流出現而波動。如果未做好適當保護，該湧入電流會造成整個系統的損壞。Inrush current refers to the highest, instantaneous input current value when an electronic device is just turned on. It is commonly found in energy supply systems for motors or electromechanical devices. When the motor or electromechanical device is turned on, a large current is instantaneously generated. Sometimes, the inrush current can be 5 to 10 times higher than the steady state current, and the steady state current only occurs briefly after the motor or electromechanical device is warmed up. The voltage value of the energy supply system fluctuates as the inrush current appears. If not properly protected, this inrush current can cause damage to the entire system.
大部分習知技術聚焦於如何避免或降低湧入電流，然而湧入電流的量測方法卻付之闕如。在湧入電流的量測方面，因為湧入電流發生的時間難以掌控，量測值變異量相當大。因此，取樣次數要多且將最大值定為湧入電流。從而，許多時間需要用於得到正確的數值。在某些傳統的瞬時停電設備中，設定的的中斷定時和實際中斷的例子之間有顯著差異，影響的結果造成了該例子產生一反電動勢。Most of the prior art focuses on how to avoid or reduce the inrush current, but the method of measuring the inrush current is not. In terms of the measurement of the inrush current, since the time at which the inrush current occurs is difficult to control, the variation of the measured value is quite large. Therefore, the number of samplings is large and the maximum value is set as the inrush current. Thus, much time is needed to get the correct value. In some conventional instantaneous power-off devices, there is a significant difference between the set interrupt timing and the actual interrupt example, and the result of the effect causes the example to generate a counter electromotive force.
雖然有觀察設備，例如示波器，能用於瞬時地停止一個電源和檢查該電源的特性，然而這樣一個觀察裝置只適合於測量迭代波形，並不適合量測僅產生一次的波形。While an observation device, such as an oscilloscope, can be used to instantaneously stop a power supply and check the characteristics of the power supply, such an observation device is only suitable for measuring iterative waveforms and is not suitable for measuring waveforms that are generated only once.
在這種停電設備裏，一切換電流段提供於一商用電源至一動力裝置線路間，且藉由開關該切換電流段，該電源關閉或開啟。在其間，一高電壓施加於外接電源輸入端子，該商用電源連接至該外接電源輸入端子，且該高電壓亦施加於外接電源輸出端子，待測的動力裝置連接至該外接電源輸出端。因此，因為一高壓施加於該外接電源輸入與輸出端子，必要地，在完全地切斷該商用電源後，與外接電源輸入端子相連的作業會結束，而在完全地切斷前面的停電設備切換電流段後，與外接電源輸出端子相連的作業會進行。為此，實施些許量測以便操作人員能知曉電力被饋送至該外接電源輸入與輸出端子，是需要的。但用於該目的量測至今仍顯不甚適當，甚至可能造成意外事故。In such a power outage device, a switching current segment is provided between a commercial power source and a power unit line, and the power source is turned off or on by switching the switching current segment. In the meantime, a high voltage is applied to the external power input terminal, the commercial power source is connected to the external power input terminal, and the high voltage is also applied to the external power output terminal, and the power device to be tested is connected to the external power output terminal. Therefore, since a high voltage is applied to the external power input and output terminals, if necessary, after the commercial power supply is completely cut off, the operation connected to the external power input terminal is ended, and the power-off device switching in front is completely cut off. After the current section, the operation connected to the external power output terminal will be performed. To this end, it is desirable to perform some measurements so that the operator can know that power is being fed to the external power input and output terminals. However, the measurement used for this purpose is still not very suitable so far, and may even cause an accident.
換句話說，傳統湧入電流量測主要需要偵測湧入電流的電流值的一觀察起始點或一連續偵測時段，以得到正確的湧入電流量測值。In other words, the conventional inrush current measurement mainly needs to detect an observation starting point or a continuous detection period of the current value of the inrush current to obtain a correct inrush current measurement value.
舉例來說，美國專利第6,628,113號揭露了一種用於準確地量測浪湧電流，如馬達開啟湧入電流，的方法與設備，如第1圖所示。從電流傳感器的一輸入信號進行監視，並當輸入信號的變化和超過一預定門檻值，就能檢測到一個浪湧電流。在一個預定的時間週期內獲得的輸入信號，是藉由一個快速採樣類比數位轉換器而得到，其將輸入信號轉換成一系列的數字化樣本，作為瞬時電流值的代表。這些數值經過處理，以計算平均電流或平方平均值電流，然後將其顯示。For example, U.S. Patent No. 6,628,113 discloses a method and apparatus for accurately measuring inrush current, such as motor inrush current, as shown in FIG. Monitoring is performed from an input signal of the current sensor, and when the input signal changes and exceeds a predetermined threshold, an inrush current can be detected. The input signal obtained over a predetermined period of time is obtained by a fast sampling analog-to-digital converter that converts the input signal into a series of digitized samples as a representative of the instantaneous current value. These values are processed to calculate the average current or squared average current and then display it.
從該發明的描述中很明顯得知，預設門檻值與時間週期 兩者缺一不可。然而，在該門檻值找到前，湧入電流可能早已出現。因此，完整且正確的量測湧入電流仍難獲得。It is apparent from the description of the invention that the threshold value and time period are preset. Both are indispensable. However, the inrush current may have already appeared before the threshold is found. Therefore, complete and correct measurement of inrush current is still difficult to obtain.
因此，用以量測湧入電流，而沒有限制門檻值與時間週期的一個較精確的量測裝置，急為所需。Therefore, a more accurate measuring device for measuring the inrush current without limiting the threshold value and time period is urgently needed.
本段文字提取和編譯本發明的部分特色；其他特色將被描述於後續段落裏。它的目的是涵蓋包含於其後專利範圍的精神與範圍中，不同的潤飾與相似的安排方式。This paragraph of text extracts and compiles some of the features of the present invention; other features will be described in subsequent paragraphs. Its purpose is to cover the spirit and scope of the subsequent patent scope, different retouching and similar arrangements.
依照本發明的一個樣態，一種湧入電流量測裝置，包含：一電流感測單元，用以接收一電流及產生與該接收之電流成比例的一電壓訊號；一類比數位轉換器，電連接於該電流感測單元，用以放大或衰減該電壓訊號、將該電壓訊號由類比式轉換為數位式，及調整電流取樣；一濾波器，電連接於該類比數位轉換器，用以調整電流取樣，以便控制來自該類比數位轉換器的數位電壓訊號的一輸出速度；一微控制器，電連接於該濾波器，用以依照該數位電壓訊號計算一對應電流值，及輸出該電流值；及一顯示單元，電連接於該微控制器，用以供一螢幕編碼電流值。According to one aspect of the present invention, an inrush current measuring device includes: a current sensing unit for receiving a current and generating a voltage signal proportional to the received current; an analog to digital converter, Connected to the current sensing unit for amplifying or attenuating the voltage signal, converting the voltage signal from analog to digital, and adjusting current sampling; a filter electrically connected to the analog digital converter for adjusting Current sampling to control an output speed of the digital voltage signal from the analog digital converter; a microcontroller electrically coupled to the filter for calculating a corresponding current value according to the digital voltage signal, and outputting the current value And a display unit electrically connected to the microcontroller for encoding a current value of the screen.
根據本案構想，該電流取樣發生於時間單元裏。According to the present concept, this current sampling takes place in a time unit.
根據本案構想，該時間單元等於數個電力訊號週期。According to the present concept, the time unit is equal to several power signal periods.
根據本案構想，該電力訊號週期是20ms或16.67ms。According to the concept of the present case, the power signal period is 20ms or 16.67ms.
根據本案構想，該濾波器為一梳狀濾波器。According to the present concept, the filter is a comb filter.
根據本案構想，該梳狀濾波器為一第四階梳狀濾波器。According to the present invention, the comb filter is a fourth-order comb filter.
根據本案構想，該湧入電流量測裝置進一步包含一多工器，裝設於該電流感測單元與類比數位轉換器間，用以切換訊號的不同頻道。According to the present invention, the inrush current measuring device further includes a multiplexer disposed between the current sensing unit and the analog digital converter for switching different channels of the signal.
根據本案構想，該湧入電流量測裝置進一步包含一記憶體模組，電連接於該微控制器，用以儲存該電流值。According to the present invention, the inrush current measuring device further includes a memory module electrically connected to the microcontroller for storing the current value.
根據本案構想，該湧入電流量測裝置進一步包含一輸出輸入控制單元，電連接於該微控制器，用以控制該電流值的輸出與輸入。According to the present invention, the inrush current measuring device further includes an output input control unit electrically connected to the microcontroller for controlling the output and input of the current value.
根據本案構想，該螢幕為一液晶顯示螢幕(LCD)。According to the concept of the present invention, the screen is a liquid crystal display (LCD).
本發明將參照下述實施例而更明確地描述。請注意本發明的實施例的以下描述，僅止於描述用途；這不意味為本發明已詳盡的描述或限制於該揭露之形式。The invention will be more clearly described with reference to the following examples. It is to be noted that the following description of the embodiments of the present invention is intended to be illustrative only.
請參閱第2圖，依照本發明的一實施例揭露一種湧入電流量測裝置。該湧入電流量測裝置10包括一電流感測單元101、一多工器102、一類比數位轉換器103、一濾波器104、一微控制器105、一記憶體模組106、一輸出輸入控制單元107與一顯示單元108。在實作上，該多工器102，類比數位轉換器103，濾波器104，微控制器105，記憶體模組106，輸出輸入控制單元107與顯示單元108能被整合於一單一積體電路晶片(被包圍在第2圖 的虛線內)中。Referring to FIG. 2, an inrush current measuring device is disclosed in accordance with an embodiment of the invention. The inrush current measuring device 10 includes a current sensing unit 101, a multiplexer 102, an analog-to-digital converter 103, a filter 104, a microcontroller 105, a memory module 106, and an output input. The control unit 107 and a display unit 108. In practice, the multiplexer 102, the analog-to-digital converter 103, the filter 104, the microcontroller 105, the memory module 106, the output input control unit 107 and the display unit 108 can be integrated into a single integrated circuit. Wafer (enclosed in Figure 2 Within the dotted line).
電流感測單元101接收自一外接電源傳來的電流，並產生與該接收電流成比例的一電壓訊號。一般來說，電流傳感器能被用來完成此目的。較佳地，霍爾效應設備或線圈也能被使用。在本實施例中，電流感測單元101是一個霍爾效應設備。類比數位轉換器103電連接於該電流感測單元101用以放大或衰減該電壓訊號，且由類比式至數位式轉換該電壓訊號。此外，類比數位轉換器103能被用來調整電流取樣，當類比轉數位處理程序進行時，這強化了類比數位轉換器103的解析度。The current sensing unit 101 receives a current from an external power source and generates a voltage signal proportional to the received current. In general, current sensors can be used to accomplish this. Preferably, a Hall effect device or coil can also be used. In the present embodiment, the current sensing unit 101 is a Hall effect device. The analog-to-digital converter 103 is electrically connected to the current sensing unit 101 for amplifying or attenuating the voltage signal, and converting the voltage signal by an analog to digital conversion. In addition, the analog to digital converter 103 can be used to adjust current sampling, which enhances the resolution of the analog digital converter 103 when analog to digital bit processing.
實作上，電流取樣發生於一時間單元。該時間單元等於數個電力訊號週期。對於不同系同而言，電力訊號週期也會不同。譬如在歐洲，交流電源系統是以60Hz在進行運作，電力訊號週期16.67ms。在台灣，交流電源系統是以50Hz在進行運作，電力訊號週期20ms。In practice, current sampling occurs in a time unit. This time unit is equal to several power signal periods. For different systems, the power signal cycle will be different. For example, in Europe, the AC power system operates at 60 Hz with a power signal cycle of 16.67 ms. In Taiwan, the AC power system operates at 50 Hz with a power signal cycle of 20 ms.
多工器102裝設於該電流感測單元101與類比數位轉換器103間。當多於一個電流感測單元101被使用於量測電流，亦即，湧入電流量測裝置10能在不同設備中，量測湧入電流，該多工器102能切換訊號的不同輸入頻道，以便不同的湧入電流值能於同時間取得。簡單地說，一個斷路器可以用來發揮多工器102的作用。The multiplexer 102 is disposed between the current sensing unit 101 and the analog digital converter 103. When more than one current sensing unit 101 is used to measure current, that is, the inrush current measuring device 10 can measure the inrush current in different devices, the multiplexer 102 can switch different input channels of the signal. So that different inrush current values can be obtained at the same time. Briefly, a circuit breaker can be used to function as multiplexer 102.
濾波器104電連接於該類比數位轉換器103。它能調整電流取樣，以便控制來自類比數位轉換器103的數位電壓訊號之輸出速度。該濾波器104為一梳狀濾波器。 較佳地，該梳狀濾波器為一第四階梳狀濾波器。電流取樣被濾波器104內的一輸出碼所控制。Filter 104 is electrically coupled to analog-like digital converter 103. It can adjust the current sampling to control the output speed of the digital voltage signal from the analog digital converter 103. The filter 104 is a comb filter. Preferably, the comb filter is a fourth-order comb filter. Current sampling is controlled by an output code within filter 104.
微控制器105電連接於該濾波器104。它能依照該數位電壓訊號與輸出的電流值，計算一對應電流值。本發明的精神在於蒐集至少5筆電流值以決定一湧入電流。電流值的輸出代表湧入電流之值，該電流值反映了在湧入電流發生時，蒐集的5筆電流值。Microcontroller 105 is electrically coupled to the filter 104. It can calculate a corresponding current value according to the digital voltage signal and the output current value. The spirit of the invention consists in collecting at least five current values to determine an inrush current. The output of the current value represents the value of the inrush current, which reflects the five current values collected when the inrush current occurs.
記憶體模組106電連接於該微控制器105，用以儲存來自微控制器105的電流值。輸出輸入控制單元107電連接於該微控制器105，用以控制來自微控制器105電流值的輸入與輸出。舉例而言，藉由按下控制盤(未繪示)的一個按鈕，使用者能選擇一顯示模式、閃爍發光二極體(LED)或於一螢幕顯示。如果多於一個電流感測單元101被使用，該輸出輸入控制單元107也能選擇哪一條連接的電線應該被監測，以量測湧入電流。顯示單元108電連接於該微控制器105。它將電流值編碼並呈現於一螢幕。在本實施例中，該螢幕為一液晶顯示螢幕(LCD)，螢幕20。值得注意的是顯示方法取決於輸出輸入控制單元107。意即該電流值被顯示單元108編碼，是基於來自輸出輸入控制單元107的指示。該被編碼的電流值也能顯示於一LED模組上(未繪示)。The memory module 106 is electrically connected to the microcontroller 105 for storing current values from the microcontroller 105. The output input control unit 107 is electrically coupled to the microcontroller 105 for controlling the input and output of current values from the microcontroller 105. For example, by pressing a button of a control panel (not shown), the user can select a display mode, a blinking LED (LED) or a screen display. If more than one current sensing unit 101 is used, the output input control unit 107 can also select which of the connected wires should be monitored to measure the inrush current. Display unit 108 is electrically coupled to the microcontroller 105. It encodes and presents the current value on a screen. In this embodiment, the screen is a liquid crystal display (LCD) screen. It is to be noted that the display method depends on the output input control unit 107. That is, the current value is encoded by the display unit 108 based on an indication from the output input control unit 107. The encoded current value can also be displayed on an LED module (not shown).
為了對該湧入電流量測裝置10如何計算湧入電流有一較佳理解，請參閱第3圖。它顯示了湧入電流的現象。在此實施例中，類比數位轉換器103的過採樣率設為 32。低通濾波器頻寬為256。類比數位轉換器103的時脈為400KHz。湧入電流量測裝置10輸出速度的均方根值為48.82 Hz(20.48ms內輸出一組)(輸出速度的均方根值=類比數位轉換器103時脈/類比數位轉換器103的過採樣率/低通濾波器頻寬=400KHz/32/256=48.82 Hz)In order to better understand how the inrush current measuring device 10 calculates the inrush current, please refer to FIG. It shows the phenomenon of inrush current. In this embodiment, the oversampling rate of the analog to digital converter 103 is set to 32. The low pass filter has a bandwidth of 256. The clock of the analog-to-digital converter 103 is 400 kHz. The rms value of the inrush current measuring device 10 is 48.82 Hz (output group within 20.48 ms) (root mean value of output speed = oversampling of the analog-to-digital converter 103 clock/analog digital converter 103) Rate / low pass filter bandwidth = 400KHz / 32 / 256 = 48.82 Hz)
當湧入電流發生時，最大的5筆電流(第3圖中標示1~5)用以計算平方平均湧入電流。即
其中I1 、I2 、I3 、I4 與I5 代表最大電流值。整個過程需耗時102.4ms。Wherein I 1 , I 2 , I 3 , I 4 and I 5 represent the maximum current value. The entire process takes 102.4ms.
當然，以上的設定能經調整以便有不同的輸出速度的均方根值。因此，愈大的輸出速度的均方根值，會有愈多的湧入電流值能被觀測。可施加到不同的交流電源系統，是本發明的一個好處。Of course, the above settings can be adjusted to have different root mean square values of the output speed. Therefore, the larger the rms value of the output speed, the more inrush current values can be observed. It can be applied to different AC power systems, which is a benefit of the present invention.
雖然本發明已以實施例揭露如上，然其並非用以限定本發明，任何所屬技術領域中具有通常知識者，在不脫離本發明之精神和範圍內，當可作些許之更動與潤飾，因此本發明之保護範圍當視後附之申請專利範圍所界定者為準。Although the present invention has been disclosed in the above embodiments, it is not intended to limit the invention, and any one of ordinary skill in the art can make some modifications and refinements without departing from the spirit and scope of the invention. The scope of the invention is defined by the scope of the appended claims.
10‧‧‧湧入電流量測裝置10‧‧‧Inrush current measuring device
101‧‧‧電流感測單元101‧‧‧ Current sensing unit
102‧‧‧多工器102‧‧‧Multiplexer
103‧‧‧類比數位轉換器103‧‧‧ Analog Digital Converter
104‧‧‧濾波器104‧‧‧ Filter
105‧‧‧微控制器105‧‧‧Microcontroller
106‧‧‧記憶體模組106‧‧‧Memory Module
107‧‧‧輸出輸入控制單元107‧‧‧Output input control unit
108‧‧‧顯示單元108‧‧‧Display unit
20‧‧‧螢幕20‧‧‧ screen
第1圖顯示一湧入電流量測裝置的習知技術。Figure 1 shows a conventional technique for inrushing a current measuring device.
第2圖為依照本發明的實施例之一湧入電流量測裝置。Figure 2 is an inrush current measuring device in accordance with an embodiment of the present invention.
第3圖為一湧入電流現象示意圖。Figure 3 is a schematic diagram of an inrush current phenomenon.
10‧‧‧湧入電流量測裝置10‧‧‧Inrush current measuring device
101‧‧‧電流感測單元101‧‧‧ Current sensing unit
102‧‧‧多工器102‧‧‧Multiplexer
103‧‧‧類比數位轉換器103‧‧‧ Analog Digital Converter
104‧‧‧濾波器104‧‧‧ Filter
105‧‧‧微控制器105‧‧‧Microcontroller
106‧‧‧記憶體模組106‧‧‧Memory Module
107‧‧‧輸出輸入控制單元107‧‧‧Output input control unit
108‧‧‧顯示單元108‧‧‧Display unit
20‧‧‧螢幕20‧‧‧ screen
Claims (8)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| TW101131557A TWI447400B (en) | 2012-08-30 | 2012-08-30 | Inrush current measuring device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| TW101131557A TWI447400B (en) | 2012-08-30 | 2012-08-30 | Inrush current measuring device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| TW201409040A TW201409040A (en) | 2014-03-01 |
| TWI447400B true TWI447400B (en) | 2014-08-01 |
Family
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| TW101131557A TWI447400B (en) | 2012-08-30 | 2012-08-30 | Inrush current measuring device |
Country Status (1)
| Country | Link |
|---|---|
| TW (1) | TWI447400B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| TWI644113B (en) * | 2018-03-06 | 2018-12-11 | 桓達科技股份有限公司 | Flow-calculating method using electromagnetic flowmeter |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| TW349170B (en) * | 1997-02-18 | 1999-01-01 | Fluke Corp | RMS converter using digital filteringby using a squaring circuit followed by an rms digital filter and a square root circuit |
| US6628113B2 (en) * | 2001-05-09 | 2003-09-30 | Fluke Corporation | Surge current measurement |
| TW201113533A (en) * | 2009-01-14 | 2011-04-16 | Qualcomm Inc | Current sensing mechanism |
-
2012
- 2012-08-30 TW TW101131557A patent/TWI447400B/en active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| TW349170B (en) * | 1997-02-18 | 1999-01-01 | Fluke Corp | RMS converter using digital filteringby using a squaring circuit followed by an rms digital filter and a square root circuit |
| US6628113B2 (en) * | 2001-05-09 | 2003-09-30 | Fluke Corporation | Surge current measurement |
| TW201113533A (en) * | 2009-01-14 | 2011-04-16 | Qualcomm Inc | Current sensing mechanism |
Also Published As
| Publication number | Publication date |
|---|---|
| TW201409040A (en) | 2014-03-01 |
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