A reactor coil segmented rod position detector and a measurement method thereof

Abstract

The present application belongs to the field of nuclear power plant, and particularly relates to a reactor measuring coil segmented rod position detector and a measuring method thereof. The detector comprises a measuring coil, a temperature compensation coil, a temperature compensation coil support groove, and a coil holder. The measuring coil is wound on the coil holder, the coil holder is provided with the temperature compensation coil support groove, and the temperature compensation coil is wound in the temperature compensation coil support groove. The measuring coil is divided into N segments, N is an integer and N is greater than or equal to 2. Each segment of the measuring coil is a continuous coil, and the N segments of the measuring coil have no overlapping parts. The present application can greatly improve the rod position measurement accuracy, reliability and applicability.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of nuclear power plants, and particularly relates to a reactor measurement coil segmented rod position detector and a measurement method thereof. BACKGROUND

[0002] A rod cluster control assembly (RCCA) is located in a high-temperature and high-pressure environment of a primary loop, and the position thereof is generally measured by using the principle of electromagnetic induction. When a control rod is at different positions in the detector, the inductance of the rod position detector changes, the excitation current of the measurement coil changes, and thus the position of the control rod is obtained.

[0003] At present, most of the rod position detectors used in nuclear power technologies are discrete coil type detectors, that is, the measurement coil is composed of a plurality of independent coils, and is distributed on the entire detector travel sleeve at a certain interval according to the measurement accuracy requirement.

[0004] The above discrete coil type rod position detector has the following disadvantages: there is a certain distance between the coils, which limits the measurement accuracy; there is electromagnetic interference between the coils, which makes the late processing of the measurement waveform difficult; the failure rate is high, and a single measurement coil failure will cause the rod position measurement to fail, etc.

[0005] In view of the disadvantages of the traditional rod position detector, the present application proposes a measurement coil segmented rod position detector and a measurement method thereof, which effectively overcomes the disadvantages of the traditional rod position measurement. SUMMARY

[0006] The present application aims to provide a reactor measurement coil segmented rod position detector and a measurement method thereof, each segment of the measurement coil of the rod position detector is continuously distributed on the control rod travel sleeve, a relationship function between the electrical parameters of each segment of the measurement coil and the position of the control rod inside is established, and a rod position measurement value with higher accuracy can be obtained.

[0007] The technical scheme for achieving the present application is as follows:

[0008] A reactor measurement coil segmented rod position detector, the detector comprising: a measurement coil, a temperature compensation coil, a temperature compensation coil support groove, and a coil holder; the measurement coil is wound on the coil holder, the temperature compensation coil support groove is installed on the coil holder, and the temperature compensation coil is wound in the temperature compensation coil support groove; the measurement coil is divided into N segments, N is an integer and N≥2; each segment of the measurement coil is a continuous coil, and the N segments of the measurement coil have no overlapping parts.

[0009] Each segment of the measurement coil is provided with a group of temperature compensation coils, each group of temperature compensation coils is wound and installed in a temperature compensation coil support groove, and the temperature compensation coil support groove is located at the upper end part or the lower end part of each segment of the measurement coil.

[0010] The detector further comprises: a holder inner support, a holder outer shell, a detector top cover, a detector base; the coil holder is a thin-walled cylinder with an end plate, the cylinder is made of non-magnetic material, and the outer diameter of the end plate is larger than the outer diameter of the cylinder; the coil holder is sleeved outside the holder inner support, and the holder outer shell is sleeved outside the coil holder; the upper part of the holder outer shell is fixedly connected with the rod position detector top cover, and the lower part of the holder outer shell is fixedly connected with the detector base.

[0011] The detector further comprises: a terminal row, external wiring of the measurement coil and the temperature compensation coil is realized through the terminal row.

[0012] The detector further comprises: a compression spring and a locking hoop, the compression spring is arranged between the top end plate of the coil holder and the lower end surface of the detector top cover, and the locking hoop is mounted on the detector top cover.

[0013] A reactor measurement coil segmented rod position detector measurement method, the method comprises:

[0014] Step 1, provide a direct current power supply for each group of temperature compensation coils, and collect the current signal in the temperature compensation coil through a current sensor;

[0015] Step 2, calculate the real-time resistance of each temperature compensation coil through voltage-current parameters;

[0016] Step 3, obtain the real-time temperature of each temperature compensation coil through the resistance conversion relationship at different temperatures;

[0017] Step 4, provide an alternating excitation power supply for each measurement coil respectively, and collect the current signal in the measurement coil through a current sensor;

[0018] Step 5, establish a relationship function between the electrical parameters of each measurement coil and the position of the control rod in the coil, and correct and compensate the position relationship function by using the real-time temperature of each temperature compensation coil obtained in step 3, to obtain the corresponding control rod position of each measurement coil;

[0019] Step 6, superimpose the control rod position information corresponding to each measurement coil to obtain the total rod position of the control rod to be measured.

[0020] The calculation formula of the real-time resistance of each temperature compensation coil in step 2 is as follows:

[0021] R N2 =U1 / i NR

[0022] Wherein, N=1, 2, 3, 4…, R N2 is the real-time resistance of the Nth temperature compensation coil at t N2 temperature, U1 is the temperature compensation coil power supply voltage value, i NRThe current value of the Nth segment of the temperature compensation coil.

[0023] The calculation formula of the real-time temperature of each segment of the temperature compensation coil in step 3 is as follows:

[0024]

[0025] Wherein, N = 1, 2, 3, 4,..., t N2 The real-time temperature of the Nth segment of the temperature compensation coil, T is the temperature compensation coil conductor resistance temperature constant, R N1 The resistance of the Nth segment of the temperature compensation coil at t N1 The resistance of the Nth segment of the temperature compensation coil at t N2 The real-time resistance of the Nth segment of the temperature compensation coil at t N2 The real-time resistance of the Nth segment of the temperature compensation coil at t N1 And t N1 Can be measured during the manufacture of the detector.

[0026] The calculation formula of the corresponding control rod position of each segment of the measurement coil in step 5 is as follows:

[0027]

[0028] Wherein, N = 1, 2, 3, 4,..., h N The length of the control rod passing through the Nth coil, k N1 The Nth segment of the measurement coil impedance influence coefficient, k N2 The Nth segment of the temperature compensation coil compensation coefficient, u2 is the measurement coil power supply voltage, i NL The current value of the Nth segment of the measurement coil.

[0029] The calculation formula of the total rod position of the control rod in step 6 is as follows:

[0030] h = h1+h2+…+h N

[0031] Wherein, h is the length of the total rod position of the control rod.

[0032] The beneficial technical effects of the present application are:

[0033] 1. The reactor measurement coil segmented rod position detector and the measurement method thereof provided by the present application, by segmenting the rod position detector measurement coil, each segment of the measurement coil is continuously distributed on the control rod stroke sleeve, the relationship function between the electrical parameters of each segment of the measurement coil and the internal position of the control rod is established, and the control rod rod position measurement value with higher precision is obtained.

[0034] 2. The segmented rod position detector with a reactor measurement coil provided by the present invention can greatly improve the rod position measurement accuracy because the measurement coil is a continuous coil; at the same time, because the measurement coil is segmented, the failure of a single segment measurement coil has little impact on the overall rod position measurement, which greatly improves the reliability and applicability of rod position measurement. Attached Figure Description

[0035] Figure 1 This is a schematic diagram of a segmented rod position detector structure for reactor measurement coils provided by the present invention;

[0036] Figure 2 This is a schematic diagram of the distribution of measurement coils in a segmented rod position detector for reactor measurement coils provided by the present invention.

[0037] In the diagram: 1-measuring coil, 2-temperature compensation coil, 3-temperature compensation coil support slot, 4-coil retainer, 5-inner support of retainer, 6-retainer housing, 7-terminal block, 8-locking clamp, 9-detector top cover, 10-compression spring, 11-detector base. Detailed Implementation

[0038] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments.

[0039] like Figure 1 As shown, the present invention provides a segmented rod position detector for reactor measurement coils, comprising: a measurement coil 1, a temperature compensation coil 2, a temperature compensation coil support groove 3, a coil retainer 4, an inner support within the retainer 5, a retainer housing 6, a terminal block 7, a locking clamp 8, a detector top cover 9, a compression spring 10, and a detector base 11.

[0040] The rod position detector's measuring coil consists of a measuring coil 1 and a temperature compensation coil 2. The coil holder 4 is a thin-walled cylinder with end plates, made of non-magnetic material, with the outer diameter of the end plates larger than the outer diameter of the cylinder. The measuring coil 1 is wound on the coil holder 4, and a temperature compensation coil support groove 3 is installed on the coil holder 4. The temperature compensation coil 2 is wound inside the temperature compensation coil support groove 3. Both the inner support 5 and the outer shell 6 of the holder are thin-walled structures. The coil holder 4 is fitted over the inner support 5, and the outer shell 6 is fitted over the coil holder 4. The upper part of the outer shell 6 is connected to the rod position detector's top cover 9 by screws, and the lower part is connected to the detector base 11 by screws and welding. The inner support 5 and the outer shell 6 provide support and protection for the measuring coil 1 and the temperature compensation coil 2. External wiring of the measuring coil 1 and the temperature compensation coil 2 is achieved through terminal blocks 7. A compression spring 10 is provided between the top end plate of the coil holder 4 and the lower end face of the detector's top cover 9, and a locking clamp 8 is installed on the detector's top cover 9.

[0041] likeFigure 2 As shown, the measurement coil 1 is composed of an inductive coil, the measurement coil 1 is divided into N segments, N is an integer and N≥2; each segment of the measurement coil is a continuous coil, wound on the rod position detector coil holder 4, and the N segments of the measurement coil have no overlapping parts; the power supply wires are led out on both sides of each segment of the measurement coil, the AC power supply is received through the power supply wires to provide excitation power for the measurement coil 1, and the current signal in the measurement coil 1 is collected through the current sensor.

[0042] Each segment of the measurement coil 1 is provided with a group of temperature compensation coils 2, each group of temperature compensation coils 2 is wound and installed in a temperature compensation coil support groove 3, and the temperature compensation coil support groove 3 is located at the upper end part or the lower end part of each segment of the measurement coil 1.

[0043] Each group of temperature compensation coils 2 is powered by a DC power supply, and the current signal in the temperature compensation coil 2 is collected through the current sensor.

[0044] The present application provides a kind of reactor measurement coil segmented rod position detector measurement method, specifically includes the following steps:

[0045] Step 1, provide DC power supply for each group of temperature compensation coils, and collect the current signal in the temperature compensation coil through the current sensor;

[0046] Step 2, the real-time resistance of each segment of temperature compensation coil is calculated by voltage-current parameter, and the calculation formula is as follows:

[0047] R N2 =U1 / i NR

[0048] Wherein, N=1, 2, 3, 4……, R N2 For the real-time resistance of the Nth segment of temperature compensation coil at t N2 Temperature, U1 is the voltage value of temperature compensation coil power supply, i NR For the current value of the Nth segment of temperature compensation coil;

[0049] Step 3, the real-time temperature of each segment of temperature compensation coil is obtained by resistance conversion relationship at different temperatures, and the calculation formula is as follows:

[0050]

[0051] Wherein, N=1, 2, 3, 4……, t N2 For the real-time temperature of the Nth segment of temperature compensation coil, T is the resistance temperature constant of temperature compensation coil conductor, R N1 For the resistance of the Nth segment of temperature compensation coil at t N1 Temperature, R N2 For the real-time resistance of the Nth segment of temperature compensation coil at t N2 Temperature, R N1 And tN1 The measurement can be obtained in a detector manufacturing process;

[0052] Step 4, an AC excitation power supply is provided for each measuring coil, and a current signal in the measuring coil is collected through a current sensor;

[0053] Step 5, a relationship function between an electrical parameter (output voltage or loop current) of each measuring coil and a position of the control rod in the coil is established, and a real-time temperature of each temperature compensation coil obtained in step 3 is used to correct and compensate the position relationship function, so that a corresponding control rod position of each measuring coil is obtained, and the calculation formula is as follows:

[0054]

[0055] Wherein, N = 1, 2, 3, 4……, h N is the length of the control rod passing through the Nth coil, k N1 is the impedance influence coefficient of the Nth measuring coil, k N2 is the compensation coefficient of the Nth temperature compensation coil, u2 is the voltage of the power supply of the measuring coil, i NL is the current value of the Nth measuring coil;

[0056] Step 6, the control rod position information corresponding to each measuring coil is superimposed to obtain the total rod position of the control rod to be measured, and the calculation formula is as follows:

[0057] h = h1 + h2 + … + h N

[0058] Wherein, h is the length of the total rod position of the control rod.

[0059] In the research project of key technologies for optimization and improvement of the third generation pressurized water reactor, the rod position detector and the measurement method thereof proposed in the present application have been tested and verified, and the test results show that the segmented measuring coil type rod position detector and the measurement method thereof proposed in the present application improve the precision, reliability and applicability of the rod position measurement.

[0060] The present application has been described in detail above in combination with the drawings and embodiments, but the present application is not limited to the above embodiments, and various changes can be made within the knowledge of those skilled in the art without departing from the purpose of the present application. The contents not described in detail in the present application can adopt the prior art.

Claims

1. A segmented rod level detector with a reactor measurement coil, characterized in that, The detector includes: a measuring coil (1), a temperature compensation coil (2), a temperature compensation coil support slot (3), and a coil holder (4); the measuring coil (1) is wound on the coil holder (4), the temperature compensation coil support slot (3) is installed on the coil holder (4), and the temperature compensation coil (2) is wound inside the temperature compensation coil support slot (3); the measuring coil (1) is divided into N segments, where N is an integer and N≥2; each segment of the measuring coil is a continuous coil, and the N segments of the measuring coil have no overlapping parts; Each measuring coil (1) is equipped with a set of temperature compensation coils (2), and each set of temperature compensation coils (2) is wound and installed in a temperature compensation coil support groove (3). The temperature compensation coil support groove (3) is located at the upper or lower end of each measuring coil (1). The detector also includes: a terminal block (7), a measuring coil (1) and a temperature compensation coil (2). External wiring is achieved through the terminal block (7).

2. The segmented rod position detector for reactor measurement coils according to claim 1, characterized in that, The detector also includes: an inner support (5), a cage housing (6), a detector top cover (9), and a detector base (11); the coil cage (4) is a thin-walled cylinder with end plates, the cylinder material is a non-magnetic material, and the outer diameter of the end plates is larger than the outer diameter of the cylinder; the coil cage (4) is fitted outside the inner support (5), and the cage housing (6) is fitted outside the coil cage (4); the upper part of the cage housing (6) is fixedly connected to the top cover (9) of the rod detector, and the lower part of the cage housing (6) is fixedly connected to the detector base (11).

3. A segmented rod position detector for reactor measurement coils according to claim 2, characterized in that, The detector also includes: a compression spring (10) and a locking clamp (8). A compression spring (10) is provided between the top end plate of the coil holder (4) and the lower end face of the detector top cover (9). A locking clamp (8) is installed on the detector top cover (9).

4. A method for measuring the position of a segmented rod-mount detector in a reactor measurement coil, comprising a segmented rod-mount detector in a reactor measurement coil according to any one of claims 1-3, characterized in that, The method includes: Step 1: Provide DC power to each group of temperature compensation coils and collect the current signal in the temperature compensation coils through a current sensor; Step 2: Calculate the real-time resistance of each temperature compensation coil segment using voltage-current parameters; Step 3: Obtain the real-time temperature of each temperature compensation coil segment by using the resistance conversion relationship at different temperatures; Step 4: Provide AC excitation power to each measuring coil segment and collect the current signal in the measuring coil through a current sensor; Step 5: Establish the relationship function between the electrical parameters of each measuring coil segment and the position of the control rod within the coil, and use the real-time temperature of each temperature compensation coil segment obtained in Step 3 to correct and compensate the position relationship function to obtain the position of the control rod corresponding to each measuring coil segment. Step 6: Superimpose the control rod position information corresponding to each measurement coil segment to obtain the total control rod position to be measured.

5. The method for measuring the position of a segmented rod detector in a reactor measurement coil according to claim 4, characterized in that, The formula for calculating the real-time resistance of each temperature compensation coil segment in step 2 is as follows: R N2 =U1 / i NR Where N = 1, 2, 3, 4..., R N2 For t N2 The real-time resistance of the Nth segment temperature compensation coil at the given temperature, U1 is the supply voltage value of the temperature compensation coil, and i NR This represents the current value of the Nth segment temperature compensation coil.

6. The method for measuring the position of a segmented rod detector in a reactor measurement coil according to claim 5, characterized in that, The formula for calculating the real-time temperature of each temperature compensation coil segment in step 3 is as follows: Where N = 1, 2, 3, 4..., t N2 R is the real-time temperature of the Nth segment temperature compensation coil, T is the temperature constant of the conductor resistance of the temperature compensation coil, and R is the temperature coefficient of resistance. N1 For t N1 The resistance of the Nth segment temperature compensation coil at the specified temperature is R. N2 For t N2 The real-time resistance, R, of the Nth segment temperature compensation coil at a given temperature. N1 and t N1 It can be measured during the detector manufacturing process.

7. The method for measuring the position of a segmented rod detector in a reactor measurement coil according to claim 6, characterized in that, The formula for calculating the position of the control rod corresponding to each segment of the measuring coil in step 5 is as follows: Where N = 1, 2, 3, 4..., h N Let k be the length of the control rod passing through the Nth coil. N1 Let k be the impedance influence coefficient of the Nth segment of the measuring coil. N2 Un is the compensation coefficient of the Nth segment temperature compensation coil, u2 is the power supply voltage of the measuring coil, and in is the compensation coefficient of the Nth segment temperature compensation coil. NL The measurement coil current value is for the Nth segment.

8. The method for measuring the position of a segmented rod detector in a reactor measurement coil according to claim 7, characterized in that, The formula for calculating the total position of the control rods in step 6 is as follows: h=h1+h2+……+h N Where h is the total length of the control rod.

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