TWM555556U - Switching driving circuit for electromagnetic contact - Google Patents

Abstract

本創作一種電磁接觸器之切換式驅動電路，包括一線圈，具有第一端、第二端及中間端，線圈由投入線圈及保持線圈組成，其中第一端與中間端為投入線圈的連接端，中間端與第二端為保持線圈的連接端，一場效電晶體連接於中間端與第二端之間並聯於保持線圈，一導通時間單元控制場效電晶體於一投入時段導通，使電流只流經投入線圈，或者導通時間單元控制場效電晶體於一保持時段開路，使電流流經投入線圈串聯保持線圈，達成投入線圈與保持線圈的切換控制，使本創作在無PWM切換電路的情況下，仍能達到降低激磁電流、功耗與線圈溫升的功效。 This invention creates a switching drive circuit for an electromagnetic contactor, including a coil with a first end, a second end, and an intermediate end. The coil is composed of an input coil and a holding coil, where the first end and the intermediate end are the connection ends of the input coil , The middle end and the second end are the connection ends of the holding coil, a field effect transistor is connected between the middle end and the second end in parallel with the holding coil, a conduction time unit controls the field effect transistor to be turned on during an input period, so that the current It only flows through the input coil, or the on-time unit controls the field effect transistor to open in a holding period, so that the current flows through the input coil in series with the holding coil to achieve the switching control of the input coil and the holding coil, which makes this creation without a PWM switching circuit. Under the circumstances, it can still achieve the effect of reducing the excitation current, power consumption and coil temperature rise.

Description

電磁接觸器之切換式驅動電路 Switching drive circuit of electromagnetic contactor

本創作係關於一種電磁接觸器之切換式驅動電路，特別是關於一種雙線圈切換驅動的電磁接觸器。 This creation relates to a switching drive circuit for an electromagnetic contactor, especially to an electromagnetic contactor that is driven by a dual coil switch.

按，電磁接觸器(Magnetic Contactor)是使用在交流電動機上的控制開關或繼電器，可控制二相電動機或三相電動機，如工業馬達、壓縮機等。一般電磁接觸器除了主接點連接交流電源與交流電動機之外，更設有輔助接點，有常開接點(或稱a接點)及常閉接點(或稱b接點)，利用一驅動電路控制線圈激磁吸持主接點閉合，使交流電動機的線路連接至交流電源。 Press, Magnetic Contactor (Magnetic Contactor) is a control switch or relay used on AC motor, can control two-phase motor or three-phase motor, such as industrial motor, compressor, etc. In addition to the main contact for connecting the AC power supply and the AC motor, the general electromagnetic contactor is also equipped with auxiliary contacts, which have normally open contacts (or a contact) and normally closed contacts (or b contact). A driving circuit controls the coil excitation to hold the main contact closed, so that the line of the AC motor is connected to the AC power supply.

而習知電磁驅動器的驅動電路是以輔助b接點來切換線圈進行投入與保持狀態，如圖1即為一種習知驅動電路的示意圖，透過輔助b接點(SW)吸持，再切換至電容抗降壓以保持線圈的電磁力，如此可省略判斷結束吸持狀態的複雜電路，達到簡化驅動電路，降低成本的目的。然而此種輔助b接點的可靠度不穩，可能發生a接點未完全閉合的狀態下，b接點已經斷路，如此將導致線圈無法正常激磁；抑或者發生b接點未切斷的狀態下，線圈持續激磁，如此造成激磁電流持續很大，最後導致線圈燒毀。 The driving circuit of the conventional electromagnetic driver uses the auxiliary b contact to switch the coil to input and maintain the state, as shown in FIG. 1 is a schematic diagram of a conventional driving circuit, through the auxiliary b contact (SW) holding, and then switch to The capacitance resists the voltage drop to maintain the electromagnetic force of the coil, so that the complicated circuit for judging the end of the holding state can be omitted, so as to simplify the driving circuit and reduce the cost. However, the reliability of this auxiliary b-contact is unstable. It may happen that the a-contact is not fully closed and the b-contact has been disconnected, which will cause the coil to fail to be excited normally; or the b-contact may not be cut off. Next, the coil continues to be excited, which causes the excitation current to continue to be large, and finally causes the coil to burn.

因此業界開發出一種使用脈沖寬度調變(PWM)技術的驅動 電路，如圖2所示，在線圈激磁投入後，利用PWM高頻切換進行線圈激磁電流的控制，以保持線圈的電磁力，優點是利用半導體開關元件進行斬波控制而形成微少電流，缺點是有電磁干擾(EMI)問題，必需增加EMI濾波元件，因此會增加電磁接觸器的體積及成本。故習知的電磁接觸器驅動電路仍有可改善的空間。 Therefore, the industry has developed a driver using pulse width modulation (PWM) technology The circuit, as shown in Figure 2, after the coil excitation is switched on, the coil excitation current is controlled by PWM high-frequency switching to maintain the electromagnetic force of the coil. The advantage is that the semiconductor switching element is used for chopping control to form a small current, the disadvantage is There are electromagnetic interference (EMI) problems, it is necessary to increase EMI filter components, so it will increase the size and cost of electromagnetic contactors. Therefore, the conventional electromagnetic contactor drive circuit still has room for improvement.

本創作的目的在於提供一種電磁接觸器之切換式驅動電路，利用線圈中間抽頭的方式，將線圈分成投入線圈與保持線圈，再透過投入線圈與保持線圈的切換控制，可在無PWM切換電路的情況下，達到降低激磁電流、功耗與線圈溫升的功效，更解決EMI干擾問題而簡化濾波電路。 The purpose of this creation is to provide a switching drive circuit for an electromagnetic contactor. By using the middle tap of the coil, the coil is divided into an input coil and a holding coil, and then through the switching control of the input coil and the holding coil Under the circumstances, the effect of reducing the excitation current, power consumption and coil temperature rise is achieved, and the problem of EMI interference is further solved and the filter circuit is simplified.

為了達成上述目的及功效，本創作主要技術特徵係在於提供一種電磁接觸器之切換式驅動電路，包括一線圈，具有第一端、第二端及中間端，線圈由投入線圈及保持線圈組成，其中第一端與中間端為投入線圈的連接端，中間端與第二端為保持線圈的連接端，一場效電晶體連接於中間端與第二端之間並聯於保持線圈，一導通時間單元控制場效電晶體於一投入時段導通，使電流只流經投入線圈，或者導通時間單元控制場效電晶體於一保持時段開路，使電流流經投入線圈串聯保持線圈，達成投入線圈與保持線圈的切換驅動。 In order to achieve the above objectives and effects, the main technical feature of this creation is to provide a switching drive circuit for an electromagnetic contactor, including a coil with a first end, a second end and an intermediate end, the coil is composed of an input coil and a holding coil, The first end and the middle end are the connection ends of the input coil, the middle end and the second end are the connection ends of the holding coil, a field effect transistor is connected between the middle end and the second end in parallel with the holding coil, and a conduction time unit Control the field effect transistor to be turned on during an input period, so that the current only flows through the input coil, or the conduction time unit controls the field effect transistor to be open during a holding period, so that the current flows through the input coil to maintain the coil in series, to achieve the input coil and the holding coil Switching driver.

為達上述目的及功效，本創作的次一技術特徵係在於提供上述電磁接觸器之切換式驅動電路，更包括一橋式整流器連接於交流電源，輸出至線圈的第一端與第二端，用以將交流電整流成全波直流電源。 In order to achieve the above purpose and effect, the next technical feature of this creation is to provide the switching drive circuit of the above electromagnetic contactor, and further includes a bridge rectifier connected to the AC power supply and output to the first end and the second end of the coil. In order to rectify the AC power into a full-wave DC power supply.

為達上述目的及功效，本創作的再一技術特徵係在於提供上 述電磁接觸器之切換式驅動電路，更包括一判斷位準單元連接於橋式整流器及導通時間單元，用以判斷全波直流電源的電壓位準，使導通時間單元依據電壓位準控制場效電晶體的導通/開路時間。 In order to achieve the above purpose and effect, another technical feature of this creation is to provide The switching drive circuit of the electromagnetic contactor further includes a judgment level unit connected to the bridge rectifier and the on-time unit for judging the voltage level of the full-wave DC power supply, so that the on-time unit controls the field effect according to the voltage level The on / off time of the transistor.

為達上述目的及功效，本創作的又一技術特徵係在於提供上述電磁接觸器之切換式驅動電路，更包括一降壓單元連接於橋式整流器，用以將全波直流電源降壓成一穩定直流電源供應至判斷位準單元及導通時間單元。 In order to achieve the above purpose and effect, another technical feature of the present invention is to provide the switching drive circuit of the above-mentioned electromagnetic contactor, and further includes a step-down unit connected to the bridge rectifier for stepping down the full-wave DC power supply into a stable DC power is supplied to the judgment level unit and the on-time unit.

10‧‧‧線圈 10‧‧‧coil

11‧‧‧投入線圈 11‧‧‧Into the coil

12‧‧‧保持線圈 12‧‧‧ Holding coil

13‧‧‧第一端 13‧‧‧The first end

14‧‧‧第二端 14‧‧‧The second end

15‧‧‧中間端 15‧‧‧middle end

20‧‧‧切換式驅動電路 20‧‧‧Switching drive circuit

21‧‧‧場效電晶體 21‧‧‧Field effect transistor

22‧‧‧導通時間單元 22‧‧‧ON time unit

23‧‧‧橋式整流器 23‧‧‧ bridge rectifier

24‧‧‧判斷位準單元 24‧‧‧judgment level unit

25‧‧‧降壓單元 25‧‧‧ Buck unit

T1‧‧‧投入時段 T1‧‧‧ Input period

圖1為習知電磁接觸器驅動電路示意圖。 FIG. 1 is a schematic diagram of a conventional electromagnetic contactor driving circuit.

圖2為習知電磁接觸器的PWM驅動電路示意圖。 2 is a schematic diagram of a PWM driving circuit of a conventional electromagnetic contactor.

圖3為本創作電磁接觸器之切換式驅動電路示意圖。 FIG. 3 is a schematic diagram of a switching drive circuit for creating an electromagnetic contactor.

圖4A及圖4B為本創作投入時段及保持時段的電流路徑示意圖。 4A and 4B are schematic diagrams of current paths during a creative investment period and a retention period.

圖5為本創作時序狀態示意圖。 Figure 5 is a schematic diagram of the state of the creation timing.

為了使 貴審查委員能更進一步瞭解本創作為達成預定目的所採取之技術、手段及功效，請參閱以下有關本創作之詳細說明與附圖，相信本創作之目的、特徵與特點，當可由此得一深入且具體之瞭解，然而所附圖式僅提供參考與說明用，並非用來對本創作加以限制者。 In order to enable your reviewer to further understand the technology, means and effects of this creation to achieve the intended purpose, please refer to the following detailed description and drawings of this creation, I believe the purpose, characteristics and characteristics of this creation For an in-depth and specific understanding, the attached drawings are provided for reference and explanation only, and are not intended to limit this creation.

請參閱圖3所示，即為本創作電磁接觸器之切換驅動電路示意圖，本創作的線圈10較佳地可設計成具有中心抽頭，使線圈10形成第一端13、第二端14及中間端15，且該線圈10由二組線圈組成，分別是投入線 圈11及保持線圈12，其中第一端13與中間端15為投入線圈11的連接端，中間端15與第二端14為保持線圈12的連接端。 Please refer to FIG. 3, which is a schematic diagram of the switching drive circuit of the electromagnetic contactor. The coil 10 of the invention can be preferably designed with a center tap, so that the coil 10 forms the first end 13, the second end 14, and the middle. End 15, and the coil 10 is composed of two sets of coils, which are input wires In the coil 11 and the holding coil 12, the first end 13 and the middle end 15 are the connecting ends of the input coil 11, and the middle end 15 and the second end 14 are the connecting ends of the holding coil 12.

本創作的切換式驅動電路20包括有一場效電晶體21、一導通時間單元22、一橋式整流器23、一判斷位準單元24及一降壓單元25。其中場效電晶體21的汲極端(D)與源極端(S)分別連接於線圈10的中間端15與第二端14之間，換言之是與保持線圈12並聯，場效電晶體21的閘極端(G)連接於導通時間單元22，場效電晶體21受導通時間單元22的控制導通或開路。其中橋式整流器23的輸入端連接至交流電源，輸出端連接至線圈10的第一端13及第二端14，橋式整流器23可將交流電源整流成全波直流電源，輸出至線圈10的第一端13及第二端14。 The switching driving circuit 20 of the present invention includes a field effect transistor 21, an on-time unit 22, a bridge rectifier 23, a judgment level unit 24 and a voltage step-down unit 25. The drain terminal (D) and source terminal (S) of the field effect transistor 21 are connected between the middle end 15 and the second end 14 of the coil 10, in other words, in parallel with the holding coil 12, the gate of the field effect transistor 21 The terminal (G) is connected to the on-time unit 22, and the field effect transistor 21 is turned on or opened under the control of the on-time unit 22. The input end of the bridge rectifier 23 is connected to an AC power source, and the output end is connected to the first end 13 and the second end 14 of the coil 10. The bridge rectifier 23 can rectify the AC power source into a full-wave DC power source and output it to the first end of the coil 10 One end 13 and the second end 14.

其中判斷位準單元24的輸入端連接於橋式整流器23的輸出端，判斷位準單元24的輸出端連接至導通時間單元22，判斷位準單元24判斷全波直流電源的電壓位準，使導通時間單元22依據電壓位準控制場效電晶體21的導通或開路時間。其中降壓單元25連接於橋式整流器23的輸出端，可將全波直流電源降壓成一穩定直流電源，供應給判斷位準單元24及導通時間單元22。 The input terminal of the judgment level unit 24 is connected to the output terminal of the bridge rectifier 23, the output terminal of the judgment level unit 24 is connected to the on-time unit 22, and the judgment level unit 24 judges the voltage level of the full-wave DC power supply, so that The on time unit 22 controls the on or open time of the field effect transistor 21 according to the voltage level. The step-down unit 25 is connected to the output end of the bridge rectifier 23, and can step down the full-wave DC power supply into a stable DC power supply, which is supplied to the judgment level unit 24 and the conduction time unit 22.

本創作的電路動作原理包括有三個時段，一投入時段、一保持時段及一釋放時段。當本創作在投入時段T1，請一併參閱圖4A及圖5所示，圖4A為本創作於投入時段的電流路徑示意圖，圖5為本創作的時序狀態示意圖。判斷位準單元24判斷全波直流電源的電壓位置達到預設值時，導通時間單元22輸出訊號給場效電晶體21，控制場效電晶體21導通，使汲極端(D)與源極端(S)之間形成短路，因此保持線圈12的中間端15與第二端14之 間也形成短路，這時電流只會流經投入線圈11，如圖4A中的虛線箭頭，驅動投入線圈11激磁產生電磁力，電磁接觸器的電磁鐵(圖中未示)作動吸持，切換電磁接觸器的複數個主接點閉合，這些主接點可連接二相或三相交流電與一電動機(圖中未示)之間，可控制電動機的啟動或關閉。 The circuit action principle of this creation includes three periods, an input period, a holding period and a release period. When the creation is in the input period T1, please refer to FIGS. 4A and 5 together. FIG. 4A is a schematic diagram of the current path of the creation in the input period, and FIG. 5 is a schematic diagram of the timing state of the creation. When the judging level unit 24 judges that the voltage position of the full-wave DC power supply reaches a preset value, the on-time unit 22 outputs a signal to the field effect transistor 21 to control the field effect transistor 21 to turn on, so that the drain terminal (D) and the source terminal ( S) a short circuit is formed between them, thus keeping the middle end 15 and the second end 14 of the coil 12 There is also a short circuit between them. At this time, the current will only flow through the input coil 11, as shown by the dashed arrow in FIG. The multiple main contacts of the contactor are closed. These main contacts can be connected between two-phase or three-phase AC power and a motor (not shown in the figure), which can control the starting or closing of the motor.

當本創作在保持時段，請一併參閱圖4B及圖5所示，圖4B為本創作保持時段的電流路徑示意圖。圖5中非T1的時段為保持時段，此時段導通時間單元22中斷給場效電晶體21的輸出訊號，因此場效電晶體21開路，電流流經投入線圈11與保持線圈12的串聯，如圖4B中的虛線箭頭，換言之電流經過整個線圈10，線圈的阻抗增大，使得流過線圈10的電流降低，但線圈10仍保持激磁狀態，電磁鐵仍維持作動吸持的閉合狀態。最後當本創作在釋放時段時，交流電為0，線圈10上的儲能電流會經第二端14流向橋式整流器23，回流至第一端13以釋放線圈10上的儲能電流。 When the creation is in the holding period, please refer to FIG. 4B and FIG. 5 together. FIG. 4B is a schematic diagram of the current path during the holding period of the creation. The non-T1 period in FIG. 5 is the holding period. During this period, the on-time unit 22 interrupts the output signal to the field effect transistor 21, so the field effect transistor 21 is open, and the current flows through the series connection of the input coil 11 and the holding coil 12, as The dashed arrow in FIG. 4B, in other words, the current passing through the entire coil 10, the impedance of the coil is increased, so that the current flowing through the coil 10 is reduced, but the coil 10 still maintains the excitation state, and the electromagnet still maintains the closed state of actuation. Finally, when the creative is in the release period, the alternating current is 0, and the energy storage current on the coil 10 will flow to the bridge rectifier 23 through the second end 14 and return to the first end 13 to release the energy storage current on the coil 10.

本創作已藉由上述相關實施例的描述，確實達到不需使用PWM切換電路，即可完成投入時段與保持時段的切換，並產生降低激磁電流、功耗與線圈溫升的功效，然而上述實施例僅為實施本創作之範例，並未限制本創作之範圍。相反地，包含於申請專利範圍之精神及範圍之修改及均等設置，均包含於本創作之範圍內。 This creation has been achieved through the description of the above related embodiments, and it is indeed achieved that the switching between the input period and the holding period can be completed without using a PWM switching circuit, and the effect of reducing the excitation current, power consumption and coil temperature rise is produced. However, the above implementation The examples are only examples of implementing this creation and do not limit the scope of this creation. On the contrary, the spirit and scope of modifications and equal settings included in the scope of patent application are included in the scope of this creation.

10‧‧‧線圈 10‧‧‧coil

11‧‧‧投入線圈 11‧‧‧Into the coil

12‧‧‧保持線圈 12‧‧‧ Holding coil

13‧‧‧第一端 13‧‧‧The first end

14‧‧‧第二端 14‧‧‧The second end

15‧‧‧中間端 15‧‧‧middle end

20‧‧‧切換式驅動電路 20‧‧‧Switching drive circuit

21‧‧‧場效電晶體 21‧‧‧Field effect transistor

22‧‧‧導通時間單元 22‧‧‧ON time unit

23‧‧‧橋式整流器 23‧‧‧ bridge rectifier

24‧‧‧判斷位準單元 24‧‧‧judgment level unit

25‧‧‧降壓單元 25‧‧‧ Buck unit

Claims (5)

一種電磁接觸器之切換式驅動電路，至少包括：一線圈，具有一第一端、一第二端及一中間端，該線圈由一投入線圈及一保持線圈組成，其中該第一端與該中間端為該投入線圈的連接端，該中間端與該第二端為該保持線圈的連接端；一場效電晶體，其汲極端與源極端分別連接於該線圈之中間端與第二端之間以並聯該保持線圈；及一導通時間單元，連接該場效電晶體的閘極端，控制該場效電晶體導通以短路該保持線圈，使電流只流經該投入線圈，以驅動該投入線圈作動在一投入時段，或者控制該場效電晶體開路，使電流流經該投入線圈與該保持線圈的串聯，以驅動該線圈作動於一保持時段。 A switching drive circuit of an electromagnetic contactor includes at least a coil having a first end, a second end and an intermediate end. The coil is composed of an input coil and a holding coil, wherein the first end is connected to the The middle end is the connection end of the input coil, and the middle end and the second end are the connection ends of the holding coil; a field effect transistor whose drain and source terminals are respectively connected to the middle end and the second end of the coil The holding coil is connected in parallel; and a conduction time unit is connected to the gate terminal of the field effect transistor to control the field effect transistor to turn on to short the holding coil so that current only flows through the input coil to drive the input coil Acting during an input period, or controlling the field effect transistor to open, so that current flows through the series connection of the input coil and the holding coil to drive the coil to actuate for a holding period. 如請求項1所述之電磁接觸器之切換式驅動電路，其中更包括一橋式整流器，輸入端連接至一交流電源及輸出端連接該線圈之第一端及第二端，用以將該交流電源整流成全波直流電源，輸出至該線圈之第一端及第二端。 The switching drive circuit of the electromagnetic contactor as described in claim 1, further comprising a bridge rectifier, the input end is connected to an AC power source and the output end is connected to the first end and the second end of the coil to The power supply is rectified into a full-wave DC power supply and output to the first and second ends of the coil. 如請求項2所述之電磁接觸器之切換式驅動電路，其中更包括一判斷位準單元，連接於該橋式整流器之輸出端及該導通時間單元，用以判斷該全波直流電源的電壓位準，使該導通時間單元依據該電壓位準控制該場效電晶體的導通/開路時間。 The switching drive circuit of the electromagnetic contactor according to claim 2, further comprising a judgment level unit connected to the output terminal of the bridge rectifier and the on-time unit for judging the voltage of the full-wave DC power supply The level enables the on-time unit to control the on / off time of the field effect transistor according to the voltage level. 如請求項3所述之電磁接觸器之切換式驅動電路，其中更包括一降壓單元，連接於該橋式整流器之輸出端及該判斷位準 單元及該導通時間單元，用以將該全波直流電源降壓成一穩定直流電源供應至該判斷位準單元及該導通時間單元。 The switching drive circuit of the electromagnetic contactor as described in claim 3, which further includes a step-down unit connected to the output end of the bridge rectifier and the judgment level The unit and the on-time unit are used to step down the full-wave DC power supply into a stable DC power supply to the judgment level unit and the on-time unit. 如請求項1所述之電磁接觸器之切換式驅動電路，其中該線圈激磁形成電磁力，使一電磁鐵吸持切換複數主接點閉合，該些主接點連接於二相或三相交流電源與一電動機之間，用以控制電動機啟動或關閉。 The switching drive circuit of the electromagnetic contactor according to claim 1, wherein the coil is excited to form an electromagnetic force, and an electromagnet is held to switch the plurality of main contacts closed, and the main contacts are connected to two-phase or three-phase AC Between the power supply and a motor, used to control the motor to start or shut down.