CN102426288A - Inverter tube current sampling circuit - Google Patents
Inverter tube current sampling circuit Download PDFInfo
- Publication number
- CN102426288A CN102426288A CN2011103271251A CN201110327125A CN102426288A CN 102426288 A CN102426288 A CN 102426288A CN 2011103271251 A CN2011103271251 A CN 2011103271251A CN 201110327125 A CN201110327125 A CN 201110327125A CN 102426288 A CN102426288 A CN 102426288A
- Authority
- CN
- China
- Prior art keywords
- inverter
- current
- current transformer
- circuit
- bridge circuit
- 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.)
- Pending
Links
Images
Abstract
The invention discloses an inverter tube current sampling circuit. The circuit comprises: a half-bridge circuit, an inverter and a current transformer. One input terminal of the inverter is connected with the half-bridge circuit and the other input terminal is connected with one end of a primary winding of the current transformer. The other end of the primary winding is connected with the half-bridge circuit. Two output terminals of the inverter are high voltage terminals. One end of a secondary winding of the current transformer is grounded and the other end of the secondary winding is connected with an anode of a rectifier diode and one end of a sampling resistor respectively. A cathode of the rectifier diode is connected with a current sampling terminal. The other end of the sampling resistor is grounded. In the invention, the primary winding of the current transformer is connected between the input terminal of the inverter and the half-bridge circuit. A skeleton of the current transformer does not need to be high-pressure-resistant. A signal of the current sampling terminal can reflect the current of the tube and stability of the tube current can be increased.
Description
[technical field]
The present invention relates to fluorescent tube, relate in particular to a kind of inverter lamp tube current sample circuit.
[background technology]
Inverter lamp tube current sample circuit of the prior art; Like Fig. 1; Comprise half-bridge circuit, inverter T1, current transformer T2, two input ends of inverter T1 6,7 are connected with half-bridge circuit, and the output terminal 3 of inverter T1 is high-pressure side+HV1; The output terminal 1 of inverter T1 is connected with an end 4 of the former limit winding of current transformer T2; The other end 3 of former limit winding is high-pressure side+HV2, an end 1 ground connection of the secondary winding of current transformer T2, and the other end 2 of secondary winding meets current sample end Isense through commutation diode D1; The negative electrode of commutation diode D1 meets current sample end Isense; Between the other end 2 of secondary winding and ground, be connected with sampling resistor R2, between an end 1 of end 4 of former limit winding and secondary winding, be connected to distributed capacitance C2, between an end 2 of end 3 of former limit winding and secondary winding, be connected to distributed capacitance C3; And between current sample end Isense and ground, being connected to filtering circuit, this filtering circuit comprises parallel resistor R1 and R3 and capacitor C 1.
Wherein, Half-bridge circuit comprises metal-oxide-semiconductor Q2 and Q1; The drain electrode 2 of metal-oxide-semiconductor Q2 connects the 400V power supply, and the source electrode 3 of metal-oxide-semiconductor Q2 is connected with the drain electrode 2 of metal-oxide-semiconductor Q1, and the grid 1 of metal-oxide-semiconductor Q2 meets drive signal Gate1 and Gate2 respectively with the grid 1 of metal-oxide-semiconductor Q1; The source ground of metal-oxide-semiconductor Q1, and between the source electrode 3 of the drain electrode 2 of metal-oxide-semiconductor Q2 and metal-oxide-semiconductor Q1, be in series with capacitor C 4 and C5; The input end 6 of inverter T1 is connected between the drain electrode 2 of source electrode 3 and metal-oxide-semiconductor Q1 of metal-oxide-semiconductor Q2, and the input end 7 of inverter T1 is connected between capacitor C 4 and the C5.
Because current transformer T2 is connected the high-pressure side and detects lamp current, require the withstand voltage height of wanting of skeleton of current transformer T2, need withstand voltage high framework material (such as LCP) to process; The WV of high-pressure side+HV2 is about 1000Vrms in addition; Frequency of operation is between 50-80KHz; This moment, capacitor C 2 had leakage current with C3; On sampling resistor R2, produce voltage, the signal of current sample end Isense will comprise two signals: 1. lamp current is through the current signal of current transformer T2 induction; 2. pass through the leakage current signal of capacitor C 3; When capacitor C 2, C3, high-pressure side+HV1 changes, all can cause the signal transformation of current sample end Isense like this, this signal just can not truly reflect lamp tube current, can not satisfy needed lamp current requirement.
[summary of the invention]
The invention provides a kind of inverter lamp tube current sample circuit, it does not require the withstand voltage height of skeleton of current transformer, and the signal of current sample end can truly reflect lamp tube current, the stability of raising lamp current.
Technical scheme of the present invention is:
A kind of inverter lamp tube current sample circuit; Comprise half-bridge circuit, inverter summation current transformer; It is characterized in that: an input end of inverter is connected with half-bridge circuit; Another input end is connected with an end of the former limit winding of current transformer, and the other end of former limit winding is connected with half-bridge circuit;
Two output terminals of inverter are respectively high-pressure side; One end ground connection of the secondary winding of current transformer; The other end of secondary winding is connected with the anode of commutation diode and an end of sampling resistor respectively, and the negative electrode of commutation diode connects the current sample end, the other end ground connection of sampling resistor.
Inverter lamp tube current sample circuit of the present invention, the former limit winding of current transformer is connected between the input end and half-bridge circuit of inverter, does not need the withstand voltage height of skeleton of current transformer; And can reduce the former limit winding of current transformer and the voltage between the secondary winding; Improve the stability of operation of current transformers; And can reduce the leakage current that is connected the distributed capacitance between former limit winding and the secondary winding; Make the signal of current sample end can truly reflect lamp tube current, improve the stability of lamp current.
[description of drawings]
Fig. 1 is the circuit theory diagrams of inverter lamp tube current sample circuit of the prior art;
Fig. 2 is the circuit theory diagrams of inverter lamp tube current sample circuit of the present invention.
[embodiment]
Below in conjunction with accompanying drawing specific embodiment of the present invention is done a detailed elaboration.
Like Fig. 2; Inverter lamp tube current sample circuit of the present invention; Comprise half-bridge circuit, inverter T1 summation current transformer T2; The input end 6 of inverter T1 is connected with half-bridge circuit, and another input end 7 is connected with an end 3 of the former limit winding of current transformer T2, and the other end 4 of former limit winding is connected with half-bridge circuit;
Two output terminals 1,3 of inverter T1 be respectively high-pressure side+HV2 ,+HV1; One end, 1 ground connection of the secondary winding of current transformer T2; The other end 2 of secondary winding is connected with the anode of commutation diode D1 and the end of sampling resistor R2 respectively; The negative electrode of commutation diode D1 meets current sample end Isense, the other end ground connection of sampling resistor R2; Between an end 1 of end 4 of former limit winding and secondary winding, be connected to distributed capacitance C2, between an end 2 of end 3 of former limit winding and secondary winding, be connected to distributed capacitance C3.
During practical implementation; Half-bridge circuit comprises metal-oxide-semiconductor Q1 and Q2; The drain electrode 2 of metal-oxide-semiconductor Q2 connects the 400V power supply, and the source electrode 3 of metal-oxide-semiconductor Q2 is connected with the drain electrode 2 of metal-oxide-semiconductor Q1, and the grid 1 of metal-oxide-semiconductor Q2 meets drive signal Gate1 and Gate2 respectively with the grid 1 of metal-oxide-semiconductor Q1; The source ground of metal-oxide-semiconductor Q1, and between the source electrode 3 of the drain electrode 2 of metal-oxide-semiconductor Q2 and metal-oxide-semiconductor Q1, be in series with capacitor C 4 and C5; The input end 6 of inverter T1 is connected between the drain electrode 2 of source electrode 3 and metal-oxide-semiconductor Q1 of metal-oxide-semiconductor Q2, and an end 4 of the former limit winding of current transformer T2 is connected between capacitor C 4 and the C5.
In addition, the stability for the signal that improves current sample end Isense further also is connected to filtering circuit between current sample end Isense and ground, and like Fig. 2, this filtering circuit can comprise parallel resistor R1, R3 and capacitor C 1.
This shows, inverter lamp tube current sample circuit of the present invention, the former limit winding of current transformer T2 is connected between the input end and half-bridge circuit of inverter T1, does not need the withstand voltage height of skeleton of current transformer T2; And can reduce the former limit winding of current transformer T2 and the voltage between the secondary winding; Improve the stability of current transformer T2 work; And can reduce the leakage current that is connected the distributed capacitance between former limit winding and the secondary winding; Make the signal of current sample end Isense can truly reflect lamp tube current, improve the stability of lamp current.
Above-described embodiment of the present invention does not constitute the qualification to protection domain of the present invention.Any modification of within spirit of the present invention and principle, being done, be equal to replacement and improvement etc., all should be included within the claim protection domain of the present invention.
Claims (3)
1. inverter lamp tube current sample circuit; Comprise half-bridge circuit, inverter summation current transformer; It is characterized in that: an input end of inverter is connected with half-bridge circuit; Another input end is connected with an end of the former limit winding of current transformer, and the other end of former limit winding is connected with half-bridge circuit;
Two output terminals of inverter are respectively high-pressure side; One end ground connection of the secondary winding of current transformer; The other end of secondary winding is connected with the anode of commutation diode and an end of sampling resistor respectively, and the negative electrode of commutation diode connects the current sample end, the other end ground connection of sampling resistor.
2. inverter lamp tube current sample circuit according to claim 1 is characterized in that: between current sample end and ground, also be connected with filtering circuit.
3. inverter lamp tube current sample circuit according to claim 2 is characterized in that: said filtering circuit comprises two resistance and the electric capacity of parallel connection.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2011103271251A CN102426288A (en) | 2011-10-25 | 2011-10-25 | Inverter tube current sampling circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2011103271251A CN102426288A (en) | 2011-10-25 | 2011-10-25 | Inverter tube current sampling circuit |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN102426288A true CN102426288A (en) | 2012-04-25 |
Family
ID=45960293
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2011103271251A Pending CN102426288A (en) | 2011-10-25 | 2011-10-25 | Inverter tube current sampling circuit |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN102426288A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104090145B (en) * | 2014-07-23 | 2017-01-18 | 武汉理工大学 | Inverter circuit current sampling circuit combined with mutual inductor and sampling resistor |
| CN110049589A (en) * | 2018-12-27 | 2019-07-23 | 浙江绍兴苏泊尔生活电器有限公司 | Determination method, electromagnetic heating circuit and the electromagnetic heating utensil of valley calibration |
| CN112816761A (en) * | 2020-12-31 | 2021-05-18 | 重庆两江卫星移动通信有限公司 | Detection circuit and method for total current of high-voltage cathode |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2001103741A (en) * | 1999-10-01 | 2001-04-13 | Toyota Autom Loom Works Ltd | Switching power source |
| CN1514253A (en) * | 2003-08-15 | 2004-07-21 | 艾默生网络能源有限公司 | Current mutual induction sampliing circuit and its resetting method |
| CN1805259A (en) * | 2004-12-08 | 2006-07-19 | 株式会社日立制作所 | Current detection circuit, and power supply apparatus, power supply system and electronic apparatus using the current detection circuit |
| CN102141583A (en) * | 2010-12-29 | 2011-08-03 | 深圳市火天光电科技有限公司 | LED current detection circuit |
| CN201967206U (en) * | 2011-01-11 | 2011-09-07 | 杭州电子科技大学 | LED drive circuit based on current transformer |
| CN202362349U (en) * | 2011-10-25 | 2012-08-01 | 深圳麦格米特电气股份有限公司 | Lamp current sampling circuit of inverter |
-
2011
- 2011-10-25 CN CN2011103271251A patent/CN102426288A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2001103741A (en) * | 1999-10-01 | 2001-04-13 | Toyota Autom Loom Works Ltd | Switching power source |
| CN1514253A (en) * | 2003-08-15 | 2004-07-21 | 艾默生网络能源有限公司 | Current mutual induction sampliing circuit and its resetting method |
| CN1805259A (en) * | 2004-12-08 | 2006-07-19 | 株式会社日立制作所 | Current detection circuit, and power supply apparatus, power supply system and electronic apparatus using the current detection circuit |
| CN102141583A (en) * | 2010-12-29 | 2011-08-03 | 深圳市火天光电科技有限公司 | LED current detection circuit |
| CN201967206U (en) * | 2011-01-11 | 2011-09-07 | 杭州电子科技大学 | LED drive circuit based on current transformer |
| CN202362349U (en) * | 2011-10-25 | 2012-08-01 | 深圳麦格米特电气股份有限公司 | Lamp current sampling circuit of inverter |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104090145B (en) * | 2014-07-23 | 2017-01-18 | 武汉理工大学 | Inverter circuit current sampling circuit combined with mutual inductor and sampling resistor |
| CN110049589A (en) * | 2018-12-27 | 2019-07-23 | 浙江绍兴苏泊尔生活电器有限公司 | Determination method, electromagnetic heating circuit and the electromagnetic heating utensil of valley calibration |
| CN110049589B (en) * | 2018-12-27 | 2021-08-24 | 浙江绍兴苏泊尔生活电器有限公司 | Determination method of valley value calibration, electromagnetic heating circuit and electromagnetic heating appliance |
| CN112816761A (en) * | 2020-12-31 | 2021-05-18 | 重庆两江卫星移动通信有限公司 | Detection circuit and method for total current of high-voltage cathode |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN104124874B (en) | Ultrahigh-frequency isolating resonant converter | |
| CN102843039B (en) | Control circuit and constant current source circuit with same | |
| CN104333231A (en) | LCC serial-parallel resonant power supply and method for increasing switching frequency by power supply | |
| CN103944402A (en) | Control method of excited push-pull converter with zero-voltage switching and excited push-pull converter | |
| CN101488719B (en) | Synchronous rectifying driver circuit suitable for voltage-multiplying rectifying | |
| CN102426288A (en) | Inverter tube current sampling circuit | |
| CN202362349U (en) | Lamp current sampling circuit of inverter | |
| CN101969722B (en) | LED drive circuit and LED lamp | |
| CN201550090U (en) | Pulse modulator | |
| CN103944384A (en) | Coupling inductance high-gain active network boost converter | |
| CN103795280A (en) | Essential safety power source | |
| CN104201874B (en) | The lossless absorption circuit and Switching Power Supply of a kind of Switching Power Supply output rectifying tube | |
| CN103066850B (en) | Isolated booster circuit, backlight module and liquid crystal indicator | |
| CN105915061A (en) | Integration forward-flyback circuit employed by leakage inductance energy | |
| CN106100330B (en) | Direct-type digital power amplifier circuit | |
| CN202068327U (en) | Boost converter | |
| CN103929067A (en) | Novel topological structure of isolated two-way DC/DC converter | |
| CN203933423U (en) | A kind of high-voltage rectification assembly | |
| CN104868719B (en) | Phase error controlled reversed polarity high-gain voltage boosting Boost conversion circuit | |
| WO2015070515A1 (en) | Power conversion device and conversion method thereof | |
| CN103078481B (en) | Input and output voltage fluctuation suppressing circuit | |
| CN105515398A (en) | High-efficiency power circuit applied to programmable DC power | |
| CN101572491A (en) | Switch power circuit and operation method thereof | |
| CN206294063U (en) | Improved-type Magnetic isolation IGBT drive circuit | |
| CN201904723U (en) | Direct current/direct current (DC/DC) converter |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| WD01 | Invention patent application deemed withdrawn after publication | ||
| WD01 | Invention patent application deemed withdrawn after publication |
Application publication date: 20120425 |