CN103728576A - Direct-current magnetic field compensation device and method for continuous electric-steel iron loss measurement - Google Patents
Direct-current magnetic field compensation device and method for continuous electric-steel iron loss measurement Download PDFInfo
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- CN103728576A CN103728576A CN201310746052.9A CN201310746052A CN103728576A CN 103728576 A CN103728576 A CN 103728576A CN 201310746052 A CN201310746052 A CN 201310746052A CN 103728576 A CN103728576 A CN 103728576A
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Abstract
The invention relates to a direct-current magnetic field compensation device and method for continuous electric-steel iron loss measurement. The direct-current magnetic field compensation device comprises a positive peak detecting circuit, a negative peak detecting circuit, an integrator and a voltage-controlled current source, wherein the positive peak detecting circuit and the negative peak detecting circuit detect the positive peak and the negative peak of a primary current signal respectively, the integrator is used for amplifying the difference between the positive peak and the negative peak of the primary current signal and driving the voltage-controlled current source through the amplified signal, and the voltage-controlled current source is used for generating a direct-current magnetic field in a compensation coil of a measuring line frame under the drive of the output signal of the integrator. The direct-current magnetic field compensation method corresponds to the direct-current magnetic field compensation device in a one-to-one mode. By the adoption of the direct-current magnetic field compensation device and method for continuous electric-steel iron loss measurement, the functions such as detection and compensation of the direct-current field in the measuring line frame are achieved, and an environment field is measured through detection of the positive peak and the negative peak of the primary current, so that a direct-current field with the opposite direction is generated, the direct-current field in the measuring line frame is zero, and accurate measurement of iron loss is achieved.
Description
Technical field
The present invention relates to silicon steel technical field, particularly relate to a kind of for electrical sheet (siliconized plate) iron loss is measured continuously D.C. magnetic field compensation system and method.
Background technology
What the continuous iron loss of electrical sheet was measured is power frequency component, therefore DC fields, and the such as stray magnetic field of terrestrial magnetic field, permanent magnet etc. all can impact AC measurment.And two kinds of silicon steel strip magnetic measurement methods that generally adopt in the world---Epstein side's circle method and SST single sheet measurement method, it has done detailed regulation respectively in IEC60404-2, IEC60404-3 standard, known its measuring circuit is closed-loop path, and DC fields is inoperative to it.But continuously iron loss is measured as the measurement of open-flux path, is not closed-loop path, if do not eliminate environment field, siliconized plate will be under alternating current-direct current stack excitation, cannot record interchange iron loss.During the continuous iron loss of existing electrical sheet is measured, as patent CN1928581A has provided a kind of silicon steel magnetic property on-line detecting system, but it does not consider the impact of DC fields at all.
Summary of the invention
Technical matters to be solved by this invention is to provide a kind of D.C. magnetic field compensation system and method for measuring for the continuous iron loss of electrical sheet, for solving continuous iron loss, measures the impact of DC fields on AC measurment.
The technical scheme that the present invention solves the problems of the technologies described above is as follows: a kind of D.C. magnetic field compensation system of measuring for the continuous iron loss of electrical sheet, it is connected with the measurement wire frame in the continuous iron loss measurement of electrical sheet, for the treatment of the primary current signal of measuring wire frame.This D.C. magnetic field compensation system comprises positive peak testing circuit, negative peak testing circuit, integrator and voltage-controlled current source;
Described positive peak testing circuit, it is for detection of the positive peak of primary current signal, and the positive peak detecting is transferred to described integrator;
Described negative peak testing circuit, it is for detection of the negative peak of primary current signal, and the negative peak detecting is transferred to described integrator;
Described integrator, its difference for the positive peak to primary current signal and negative peak is amplified, and with amplify after signal driver described in voltage-controlled current source;
Described voltage-controlled current source, it,, under the driving in described integrator output signal, produces D.C. magnetic field in the compensating coil of described measurement wire frame.
On the basis of technique scheme, the present invention can also do following improvement.
Further, described voltage-controlled current source is bipolar current source.
Further, described integrator comprises the first resistance R 1, the second resistance R 2, the first operational amplifier A 1 and capacitor C;
The reversed-phase output of described the first operational amplifier A 1 connects respectively described the first resistance R 1 and the second resistance R 2, and the other end of described the first resistance R 1 and the second resistance R 2 is respectively as first input end and second input end of described integrator, the first input end of described integrator connects the output terminal of described positive peak testing circuit, the second input end of described integrator connects the output terminal of described negative peak testing circuit, and the positive input end grounding of described the first operational amplifier A 1;
The output terminal of described the first operational amplifier A 1 is as the output terminal of described integrator, and is connected with capacitor C between the inverting input of described the first operational amplifier A 1 and output terminal.
Further, described voltage-controlled current source comprises: the second operational amplifier A 2, OCL complementary output circuit and feedback resistance Rs;
The normal phase input end of described the second operational amplifier A 2 connects the output terminal of described integrator, and as the input end of described voltage-controlled current source;
The inverting input of described the second operational amplifier A 2 is by feedback resistance Rs ground connection, and the inverting input of described the second operational amplifier A 2 is as the first output terminal of described voltage-controlled current source;
The output terminal of described the second operational amplifier A 2 connects the input end of described OCL complementary output circuit, and the output terminal of described OCL complementary output circuit second output terminal that is described voltage-controlled current source;
The first output terminal of described voltage-controlled current source is all connected described measurement wire frame with the second output terminal.
Further, described OCL complementary output circuit comprises: NPN transistor T1, PNP transistor T2, the 3rd resistance R 3, the 4th resistance R 4, the first diode D1 and the second diode D2;
Described NPN transistor T1 is connected with the base stage of PNP transistor T2, and is connected with the output terminal of described the second operational amplifier A 2 as the input end of described OCL complementary output circuit;
The collector of described NPN transistor T1 and PNP transistor T2 is connected with positive supply V+ and the negative supply V-of described the second operational amplifier A 2 respectively;
The emitter of described NPN transistor T1 and PNP transistor T2 links together after being connected respectively the 3rd resistance R 3 and the 4th resistance R 4, as the output terminal of described OCL complementary output circuit, described output terminal connects respectively the anode of the first diode D1 and the negative electrode of the second diode D2, and the negative electrode of described the first diode D1 connects the collector of described NPN transistor T1, the collector of PNP transistor T2 described in the anodic bonding of described the second diode D2.
Further, the positive supply V+ of described the second operational amplifier A 2, its magnitude of voltage is greater than the voltage positive peak at the compensating coil two ends of measuring wire frame, for guaranteeing that the first diode D1 is under reverse voltage all the time; The negative supply V-of described the second operational amplifier A 2, its magnitude of voltage is less than the voltage negative peak value at the compensating coil two ends of measuring wire frame, for guaranteeing that the second diode D2 is under reverse voltage all the time.
Corresponding above-mentioned D.C. magnetic field compensation system, technical scheme of the present invention also comprises a kind of D.C. magnetic field compensation method of measuring for the continuous iron loss of electrical sheet, for the treatment of the primary current signal of measuring wire frame, comprising:
Step 1, respectively positive peak and the negative peak of detection of primary current signal;
Step 2, amplifies the difference of the positive peak of primary current signal and negative peak, and produces D.C. magnetic field with the signal driver voltage-controlled current source after amplifying measuring in the compensating coil of wire frame.
Further, described voltage-controlled current source is bipolar current source.
Further, adopt OCL complementary output mode to design described voltage-controlled current source, specific design mode is with reference to above-mentioned D.C. magnetic field compensation system.
Further, the magnitude of voltage of the positive supply of described voltage-controlled current source is greater than the voltage positive peak at compensating coil two ends; The magnitude of voltage of the negative supply of described voltage-controlled current source is less than the voltage negative peak value at compensating coil two ends.
The invention has the beneficial effects as follows: the present invention has completed the function such as detection, compensation of measuring DC fields in wire frame, its size by the positive negative peak of detection of primary electric current is come measurement environment field, thereby produce rightabout DC fields, making to measure DC fields in wire frame is zero, realizes the Measurement accuracy of iron loss.
Accompanying drawing explanation
Fig. 1 is the structural representation of D.C. magnetic field compensation system of the present invention;
Fig. 2 is the schematic flow sheet of D.C. magnetic field compensation method of the present invention.
Embodiment
Below in conjunction with accompanying drawing, principle of the present invention and feature are described, example, only for explaining the present invention, is not intended to limit scope of the present invention.
As shown in Figure 1, the present embodiment relates to a kind of D.C. magnetic field compensation system of measuring for the continuous iron loss of electrical sheet, it belongs to the vitals of the continuous iron loss measurement mechanism of electrical sheet, major function is to process the primary current signal of the measurement wire frame in the continuous iron loss measurement mechanism of electrical sheet, and the primary current signal of measuring wire frame need just can input to the D.C. magnetic field compensation system of the present embodiment after primary current amplifier amplifies, and primary current amplifier also can be integrated in this D.C. magnetic field compensation system.This D.C. magnetic field compensation system comprises positive peak testing circuit, negative peak testing circuit, integrator and voltage-controlled current source;
Described positive peak testing circuit, it is for detection of the positive peak of primary current signal, and the positive peak detecting is transferred to described integrator;
Described negative peak testing circuit, it is for detection of the negative peak of primary current signal, and the negative peak detecting is transferred to described integrator;
Described integrator, its difference for the positive peak to primary current signal and negative peak is amplified, and with amplify after signal driver described in voltage-controlled current source;
Described voltage-controlled current source, it,, under the driving in described integrator output signal, produces D.C. magnetic field in the compensating coil of described measurement wire frame.Here, described voltage-controlled current source, the AC load of coil by way of compensation, its impedance is enough large, therefore can ignore the impact that iron loss is measured.
In the present embodiment, as shown in Figure 1, described integrator comprises the first resistance R 1, the second resistance R 2, the first operational amplifier A 1 and capacitor C.
The reversed-phase output of described the first operational amplifier A 1 connects respectively described the first resistance R 1 and the second resistance R 2, and the other end of described the first resistance R 1 and the second resistance R 2 is respectively as first input end and second input end of described integrator, the first input end of described integrator connects the output terminal of described positive peak testing circuit, the second input end of described integrator connects the output terminal of described negative peak testing circuit, and the positive input end grounding of described the first operational amplifier A 1.
The output terminal of described the first operational amplifier A 1 is as the output terminal of described integrator, and is connected with capacitor C between the inverting input of described the first operational amplifier A 1 and output terminal.
Voltage-controlled current source of the present invention is bipolar current source, adopts OCL complementary output mode to design, and preferably following design, as shown in Figure 1, comprising: the second operational amplifier A 2, OCL complementary output circuit and feedback resistance Rs.
The normal phase input end of described the second operational amplifier A 2 connects the output terminal of described integrator, and as the input end of described voltage-controlled current source; The inverting input of described the second operational amplifier A 2 is by feedback resistance Rs ground connection, and the inverting input of described the second operational amplifier A 2 is as the first output terminal of described voltage-controlled current source; The output terminal of described the second operational amplifier A 2 connects the input end of described OCL complementary output circuit, and the output terminal of described OCL complementary output circuit second output terminal that is described voltage-controlled current source; The first output terminal of described voltage-controlled current source is all connected described measurement wire frame with the second output terminal.
In addition, described OCL complementary output circuit adopts conventional OCL power amplification circuit, as shown in Figure 1, preferably design proposal is: adopt NPN transistor T1, PNP transistor T2, the 3rd resistance R 3, the 4th resistance R 4, the first diode D1 and the second diode D2.
Described NPN transistor T1 is connected with the base stage of PNP transistor T2, and is connected with the output terminal of described the second operational amplifier A 2 as the input end of described OCL complementary output circuit; The collector of described NPN transistor T1 and PNP transistor T2 is connected with positive supply V+ and the negative supply V-of described the second operational amplifier A 2 respectively; The emitter of described NPN transistor T1 and PNP transistor T2 links together after being connected respectively the 3rd resistance R 3 and the 4th resistance R 4, as the output terminal of described OCL complementary output circuit, described output terminal connects respectively the anode of the first diode D1 and the negative electrode of the second diode D2, and the negative electrode of described the first diode D1 connects the collector of described NPN transistor T1, the collector of PNP transistor T2 described in the anodic bonding of described the second diode D2.
In the present embodiment, the positive supply V+ of described the second operational amplifier A 2, its magnitude of voltage is greater than the voltage positive peak at the compensating coil two ends of measuring wire frame, for guaranteeing that the first diode D1 is under reverse voltage all the time; The negative supply V-of described the second operational amplifier A 2, its magnitude of voltage is less than the voltage negative peak value at the compensating coil two ends of measuring wire frame, for guaranteeing that the second diode D2 is under reverse voltage all the time.
As shown in Figure 2, corresponding above-mentioned D.C. magnetic field compensation system, the present embodiment also comprises a kind of D.C. magnetic field compensation method of measuring for the continuous iron loss of electrical sheet, concrete steps are:
Step 1, respectively positive peak and the negative peak of detection of primary current signal;
Step 2, amplifies the difference of the positive peak of primary current signal and negative peak, and produces D.C. magnetic field with the signal driver voltage-controlled current source after amplifying measuring in the compensating coil of wire frame.
With above-mentioned D.C. magnetic field compensation system, described voltage-controlled current source is bipolar current source, and adopt OCL complementary output mode to design described voltage-controlled current source, require the magnitude of voltage of the positive supply of described voltage-controlled current source to be greater than the voltage positive peak at compensating coil two ends, the magnitude of voltage of the negative supply of described voltage-controlled current source is less than the voltage negative peak value at compensating coil two ends.
The principle of work of this D.C. magnetic field compensation method is identical with above-mentioned D.C. magnetic field compensation system with physical circuit design, no longer state more.
The foregoing is only preferred embodiment of the present invention, in order to limit the present invention, within the spirit and principles in the present invention not all, any modification of doing, be equal to replacement, improvement etc., within all should being included in protection scope of the present invention.
Claims (10)
1. a D.C. magnetic field compensation system of measuring for the continuous iron loss of electrical sheet, it is connected with the measurement wire frame in the continuous iron loss measurement of electrical sheet, for the treatment of the primary current signal of measuring wire frame, it is characterized in that, comprise positive peak testing circuit, negative peak testing circuit, integrator and voltage-controlled current source;
Described positive peak testing circuit, it is for detection of the positive peak of primary current signal, and the positive peak detecting is transferred to described integrator;
Described negative peak testing circuit, it is for detection of the negative peak of primary current signal, and the negative peak detecting is transferred to described integrator;
Described integrator, its difference for the positive peak to primary current signal and negative peak is amplified, and with amplify after signal driver described in voltage-controlled current source;
Described voltage-controlled current source, it,, under the driving in described integrator output signal, produces D.C. magnetic field in the compensating coil of described measurement wire frame.
2. D.C. magnetic field compensation system according to claim 1, is characterized in that, described voltage-controlled current source is bipolar current source.
3. D.C. magnetic field compensation system according to claim 1 and 2, is characterized in that, described integrator comprises the first resistance R 1, the second resistance R 2, the first operational amplifier A 1 and capacitor C;
The reversed-phase output of described the first operational amplifier A 1 connects respectively described the first resistance R 1 and the second resistance R 2, and the other end of described the first resistance R 1 and the second resistance R 2 is respectively as first input end and second input end of described integrator, the first input end of described integrator connects the output terminal of described positive peak testing circuit, the second input end of described integrator connects the output terminal of described negative peak testing circuit, and the positive input end grounding of described the first operational amplifier A 1;
The output terminal of described the first operational amplifier A 1 is as the output terminal of described integrator, and is connected with capacitor C between the inverting input of described the first operational amplifier A 1 and output terminal.
4. D.C. magnetic field compensation system according to claim 1 and 2, is characterized in that, described voltage-controlled current source comprises: the second operational amplifier A 2, OCL complementary output circuit and feedback resistance Rs;
The normal phase input end of described the second operational amplifier A 2 connects the output terminal of described integrator, and as the input end of described voltage-controlled current source;
The inverting input of described the second operational amplifier A 2 is by feedback resistance Rs ground connection, and the inverting input of described the second operational amplifier A 2 is as the first output terminal of described voltage-controlled current source;
The output terminal of described the second operational amplifier A 2 connects the input end of described OCL complementary output circuit, and the output terminal of described OCL complementary output circuit second output terminal that is described voltage-controlled current source;
The first output terminal of described voltage-controlled current source is all connected described measurement wire frame with the second output terminal.
5. D.C. magnetic field compensation system according to claim 4, is characterized in that, described OCL complementary output circuit comprises: NPN transistor T1, PNP transistor T2, the 3rd resistance R 3, the 4th resistance R 4, the first diode D1 and the second diode D2;
Described NPN transistor T1 is connected with the base stage of PNP transistor T2, and is connected with the output terminal of described the second operational amplifier A 2 as the input end of described OCL complementary output circuit;
The collector of described NPN transistor T1 and PNP transistor T2 is connected with positive supply V+ and the negative supply V-of described the second operational amplifier A 2 respectively;
The emitter of described NPN transistor T1 and PNP transistor T2 links together after being connected respectively the 3rd resistance R 3 and the 4th resistance R 4, as the output terminal of described OCL complementary output circuit, described output terminal connects respectively the anode of the first diode D1 and the negative electrode of the second diode D2, and the negative electrode of described the first diode D1 connects the collector of described NPN transistor T1, the collector of PNP transistor T2 described in the anodic bonding of described the second diode D2.
6. D.C. magnetic field compensation system according to claim 5, it is characterized in that, the positive supply V+ of described the second operational amplifier A 2, its magnitude of voltage is greater than the voltage positive peak at the compensating coil two ends of measuring wire frame, for guaranteeing that the first diode D1 is under reverse voltage all the time;
The negative supply V-of described the second operational amplifier A 2, its magnitude of voltage is less than the voltage negative peak value at the compensating coil two ends of measuring wire frame, for guaranteeing that the second diode D2 is under reverse voltage all the time.
7. a D.C. magnetic field compensation method of measuring for the continuous iron loss of electrical sheet, it for the treatment of the primary current signal of the measurement wire frame in the continuous iron loss measurement of electrical sheet, is characterized in that, comprising:
Step 1, respectively positive peak and the negative peak of detection of primary current signal;
Step 2, amplifies the difference of the positive peak of primary current signal and negative peak, and produces D.C. magnetic field with the signal driver voltage-controlled current source after amplifying measuring in the compensating coil of wire frame.
8. D.C. magnetic field compensation method according to claim 7, is characterized in that, described voltage-controlled current source is bipolar current source.
9. according to the D.C. magnetic field compensation method described in claim 7 or 8, it is characterized in that, adopt OCL complementary output mode to design described voltage-controlled current source.
10. according to the D.C. magnetic field compensation method described in claim 7 or 8, it is characterized in that, the magnitude of voltage of the positive supply of described voltage-controlled current source is greater than the voltage positive peak at compensating coil two ends; The magnitude of voltage of the negative supply of described voltage-controlled current source is less than the voltage negative peak value at compensating coil two ends.
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