Sectional rod position detector for reactor measuring coil and measuring method thereof

Abstract

The invention belongs to the field of nuclear power stations, and particularly relates to a reactor measuring coil sectional type 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, a temperature compensation coil supporting groove is formed in the coil holder, and the temperature compensation coil is wound in the temperature compensation coil supporting groove; the measuring coil is divided into N sections, and N is an integer greater than or equal to 2; each section of measuring coil is a continuous coil, and the N sections of measuring coils have no overlapped part. According to the invention, the rod position measurement precision, the rod position measurement reliability and the rod position measurement applicability can be greatly improved.

Description

Technical Field

[0001] The invention belongs to the field of nuclear power plants, and in particular relates to a reactor measuring coil segmented rod position detector and a measuring method thereof. Background Art

[0002] The rod cluster control assembly (RCCA) is located in a high temperature and high pressure environment of the primary circuit, and its position is generally measured using the principle of electromagnetic induction. When the control rod is in different positions in the detector, the inductance of the rod position detector changes, and the excitation current of the measuring coil changes, thereby obtaining the control rod position.

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

[0004] The above-mentioned discrete coil rod position detector has the following shortcomings: there is a certain distance between the coils, which limits the measurement accuracy; there is electromagnetic interference between the coils, which makes it difficult to process the measurement waveform later; the failure rate is high, and the failure of a single measurement coil will cause the rod position measurement to fail.

[0005] In view of the shortcomings of traditional rod position detectors, the present invention proposes a measuring coil segmented rod position detector and a measuring method thereof, which effectively overcomes the shortcomings of traditional rod position measurement. Summary of the invention

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

[0007] The technical solution to achieve the purpose of the present invention is:

[0008] A reactor measuring coil segmented rod position detector, the detector comprising: 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 a 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≥2; each segment of the measuring coil is a continuous coil, and the N segments of the measuring coil have no overlapping parts.

[0009] Each measuring coil is equipped with a set of temperature compensation coils, each set of temperature compensation coils is wound and installed in a temperature compensation coil support slot, and the temperature compensation coil support slot is located at the upper end or the lower end of each measuring coil.

[0010] The detector also includes: an inner support of a holder, an outer shell of a holder, a detector top cover, and a detector base; the coil holder is a thin-walled cylinder with an end plate, the cylinder material is a 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 on the outside of the inner support of the holder, and the outer shell of the holder is sleeved on the outside of the coil holder; the upper part of the outer shell of the holder is fixedly connected to the top cover of the rod position detector, and the lower part of the outer shell of the holder is fixedly connected to the detector base.

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

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

[0013] A reactor measuring coil segmented rod position detector measuring method, the method comprising:

[0014] Step 1, providing a DC power supply to each set of temperature compensation coils, and collecting current signals in the temperature compensation coils 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 AC excitation power supply to each measuring coil, and collect the current signal in the measuring coil through a current sensor;

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

[0019] Step 6: Superimpose the control rod position information corresponding to each measuring coil to obtain the total control rod position that needs to be measured.

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

[0021] R N2 =U 1 / i NR

[0022] Where N = 1, 2, 3, 4, ..., R N2 t N2 Real-time resistance of the Nth temperature compensation coil at the temperature, U 1is the supply voltage value of the temperature compensation coil, i NR is the current value of the Nth temperature compensation coil.

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

[0024]

[0025] Where N = 1, 2, 3, 4, ..., t N2 is the real-time temperature of the Nth temperature compensation coil, T is the temperature constant of the conductor resistance of the temperature compensation coil, R N1 t N1 The resistance of the Nth temperature compensation coil at the temperature, R N2 t N2 The real-time resistance of the Nth temperature compensation coil at the temperature, R N1 and t N1 It can be measured during the detector manufacturing process.

[0026] The calculation formula for the control rod position corresponding to each measuring coil in step 5 is as follows:

[0027]

[0028] Where N = 1, 2, 3, 4, ..., h N is the length of the control rod passing through the Nth coil, k N1 k is the influence coefficient of the impedance of the measuring coil in the Nth section, N2 is the compensation coefficient of the Nth temperature compensation coil, u 2 The power supply voltage for the measuring coil, i NL Measure the coil current value for the Nth segment.

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

[0030] h=h 1 +h 2 +……+h N

[0031] Where h is the total length of the control rods.

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

[0033] 1. The present invention provides a reactor measuring coil segmented rod position detector and a measuring method thereof. The rod position detector measuring coil is designed in segments, each segment of the measuring coil is continuously distributed on the control rod travel sleeve, and a relationship function between the electrical parameters of each segment of the measuring coil and the position of the control rod inside it is established, so as to obtain a more accurate control rod position measurement value.

[0034] 2. The reactor measuring coil segmented rod position detector provided by the present invention can greatly improve the rod position measurement accuracy because the measuring coil is a continuous coil; at the same time, because the measuring coil is a segmented design, the failure of a single-segment measuring coil has little effect on the overall rod position measurement, which greatly improves the reliability and applicability of the rod position measurement. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 A schematic diagram of the structure of a reactor measurement coil segmented rod position detector provided by the present invention;

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

[0037] In the figure: 1- measuring coil, 2- temperature compensation coil, 3- temperature compensation coil support groove, 4- coil holder, 5- holder inner support, 6- holder housing, 7- terminal block, 8- locking hoop, 9- detector top cover, 10- compression spring, 11- detector base. DETAILED DESCRIPTION

[0038] The present invention is further described in detail below with reference to the accompanying drawings and embodiments.

[0039] like Figure 1 As shown, a reactor measuring coil segmented rod position detector provided by the present invention includes: a measuring coil 1, a temperature compensation coil 2, a temperature compensation coil support groove 3, a coil holder 4, a holder inner support 5, a holder outer shell 6, a terminal block 7, a locking hoop 8, a detector top cover 9, a compression spring 10, and a detector base 11.

[0040] The rod position detector measuring coil is composed of a measuring coil 1 and a temperature compensation coil 2. The coil holder 4 is a thin-walled cylinder with an end plate, the cylinder material is a non-magnetic material, and the outer diameter of the end plate is larger than the outer diameter of the cylinder; the measuring coil 1 is wound on the coil holder 4, and the coil holder 4 is installed with a temperature compensation coil support groove 3, and the temperature compensation coil 2 is wound in the temperature compensation coil support groove 3; the inner support 5 of the holder and the outer shell 6 of the holder are both thin-walled structures, the coil holder 4 is sleeved outside the inner support 5 of the holder, and the outer shell 6 of the holder is sleeved outside the coil holder 4; the upper part of the outer shell 6 of the holder is connected to the top cover 9 of the rod position detector by screws, and the lower part of the outer shell 6 of the holder is connected to the base 11 of the detector by screws and welding, and the inner support 5 of the holder and the outer shell 6 of the holder provide support and protection for the measuring coil 1 and the temperature compensation coil 2; the external wiring of the measuring coil 1 and the temperature compensation coil 2 is realized through the terminal block 7. A compression spring 10 is provided between the top end plate of the coil holder 4 and the lower end surface of the detector top cover 9, and a locking hoop 8 is installed on the detector top cover 9.

[0041] like Figure 2 As shown, the measuring coil 1 is composed of an induction coil, and the measuring coil 1 is divided into N sections, N is an integer and N≥2; each section of the measuring coil is a continuous coil, which is wound on the rod position detector coil holder 4, and the N sections of the measuring coil have no overlapping parts; power supply wiring is led out from both sides of each measuring coil, and an AC power supply is received through the power supply wiring to provide an excitation power supply for it, and the current signal in the measuring coil 1 is collected through a current sensor.

[0042] Each measuring coil 1 is equipped with a set of temperature compensation coils 2 . Each set of temperature compensation coils 2 is wound and installed in a temperature compensation coil support slot 3 . The temperature compensation coil support slot 3 is located at the upper end or the lower end of each measuring coil 1 .

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

[0044] The present invention provides a reactor measuring coil segmented rod position detector measuring method, which specifically comprises the following steps:

[0045] Step 1, providing a DC power supply to each set of temperature compensation coils, and collecting current signals in the temperature compensation coils through a current sensor;

[0046] Step 2: Calculate the real-time resistance of each temperature compensation coil using the voltage-current parameters. The calculation formula is as follows:

[0047] R N2 =U 1 / i NR

[0048] Where N = 1, 2, 3, 4, ..., R N2 t N2 Real-time resistance of the Nth temperature compensation coil at the temperature, U 1 is the supply voltage value of the temperature compensation coil, i NR is the current value of the Nth temperature compensation coil;

[0049] Step 3: Obtain the real-time temperature of each temperature compensation coil through the resistance conversion relationship at different temperatures. The calculation formula is as follows:

[0050]

[0051] Where N = 1, 2, 3, 4, ..., t N2 is the real-time temperature of the Nth temperature compensation coil, T is the temperature constant of the conductor resistance of the temperature compensation coil, R N1 t N1 The resistance of the Nth temperature compensation coil at the temperature, R N2 t N2The real-time resistance of the Nth temperature compensation coil at the temperature, R N1 and t N1 It can be measured during the detector manufacturing process;

[0052] Step 4: Provide an AC excitation power supply to each measuring coil, and collect the current signal in the measuring coil through a current sensor;

[0053] Step 5: Establish a relationship function between the electrical parameters (output voltage or loop current) of each measuring coil and the position of the control rod in the coil, and use the real-time temperature of each temperature compensation coil obtained in step 3 to correct and compensate the position relationship function to obtain the control rod position corresponding to each measuring coil. The calculation formula is as follows:

[0054]

[0055] Where N = 1, 2, 3, 4, ..., h N is the length of the control rod passing through the Nth coil, k N1 k is the influence coefficient of the impedance of the measuring coil in the Nth section, N2 is the compensation coefficient of the Nth temperature compensation coil, u 2 The power supply voltage for the measuring coil, i NL Measure the coil current value for the Nth segment;

[0056] Step 6: Superimpose the control rod position information corresponding to each measuring coil to obtain the total control rod position to be measured. The calculation formula is as follows:

[0057] h=h 1 +h 2 +……+h N

[0058] Where h is the total length of the control rods.

[0059] In the key technology research project for optimizing and improving the third-generation pressurized water reactor, the rod position detector and its measurement method proposed in the present invention have been experimentally verified. The test results show that the measuring coil segmented rod position detector and its measurement method proposed in the present invention improve the accuracy, reliability and applicability of the rod position measurement.

[0060] The present invention is described in detail above with reference to the accompanying drawings and embodiments, but the present invention is not limited to the above embodiments, and various changes can be made within the knowledge of ordinary technicians in the field without departing from the purpose of the present invention. The contents not described in detail in the present invention can adopt the existing technology.

Claims

1. A reactor measuring coil segmented rod position detector, characterized in that: The detector comprises: a measuring coil (1), a temperature compensation coil (2), a temperature compensation coil support groove (3), and a coil holder (4); the measuring coil (1) is wound on the coil holder (4), the coil holder (4) is provided with a temperature compensation coil support groove (3), and the temperature compensation coil (2) is wound in the temperature compensation coil support groove (3); the measuring coil (1) is divided into N sections, N is an integer and N≥2; each section of the measuring coil is a continuous coil, and the N sections of the measuring coil have no overlapping parts.

2. A reactor measuring coil segmented rod position detector according to claim 1, characterized in that: Each measuring coil (1) is equipped 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 or the lower end of each measuring coil (1).

3. The reactor measuring coil segmented rod position detector according to claim 1, characterized in that: The detector further comprises: a retaining frame inner support (5), a retaining frame outer shell (6), a detector top cover (9), and a detector base (11); the coil retaining frame (4) is a thin-walled cylinder with an end plate, the cylinder body material is a non-magnetic material, and the outer diameter of the end plate is larger than the outer diameter of the cylinder; the coil retaining frame (4) is sleeved on the outside of the retaining frame inner support (5), and the retaining frame outer shell (6) is sleeved on the outside of the coil retaining frame (4); the upper part of the retaining frame outer shell (6) is fixedly connected to the rod position detector top cover (9), and the lower part of the retaining frame outer shell (6) is fixedly connected to the detector base (11).

4. The reactor measuring coil segmented rod position detector according to claim 1, characterized in that: The detector further comprises a terminal block (7), and external wiring of the measuring coil (1) and the temperature compensation coil (2) is realized through the terminal block (7).

5. The reactor measuring coil segmented rod position detector according to claim 3, characterized in that: The detector further comprises: a compression spring (10) and a locking hoop (8); a compression spring (10) is arranged between the top end plate of the coil holder (4) and the lower end surface of the detector top cover (9); and a locking hoop (8) is installed on the detector top cover (9).

6. A reactor measuring coil segmented rod position detector measurement method, using a reactor measuring coil segmented rod position detector according to claim 1, characterized in that: The method comprises: Step 1, providing a DC power supply to each set of temperature compensation coils, and collecting current signals in the temperature compensation coils through a current sensor; Step 2, calculate the real-time resistance of each temperature compensation coil through voltage-current parameters; Step 3, obtain the real-time temperature of each temperature compensation coil through the resistance conversion relationship at different temperatures; Step 4: Provide an AC excitation power supply to each measuring coil, and collect the current signal in the measuring coil through a current sensor; Step 5: Establish a relationship function between the electrical parameters of each measuring coil and the position of the control rod in the coil, and use the real-time temperature of each temperature compensation coil obtained in step 3 to correct and compensate the position relationship function to obtain the control rod position corresponding to each measuring coil; Step 6: Superimpose the control rod position information corresponding to each measuring coil to obtain the total control rod position that needs to be measured.

7. A reactor measuring coil segmented rod position detector measuring method according to claim 6, characterized in that: The calculation formula for the real-time resistance of each temperature compensation coil in step 2 is as follows: R N2 =U1 / i NR Where N = 1, 2, 3, 4, ..., R N2 t N2 The real-time resistance of the Nth temperature compensation coil at the temperature, U1 is the supply voltage value of the temperature compensation coil, i NR is the current value of the Nth temperature compensation coil.

8. The reactor measurement coil segmented rod position detector measurement method according to claim 7, characterized in that: The calculation formula for the real-time temperature of each temperature compensation coil in step 3 is as follows: Where N = 1, 2, 3, 4, ..., t N2 is the real-time temperature of the Nth temperature compensation coil, T is the temperature constant of the conductor resistance of the temperature compensation coil, R N1 t N1 The resistance of the Nth temperature compensation coil at the temperature, R N2 t N2 The real-time resistance of the Nth temperature compensation coil at the temperature, R N1 and t N1 It can be measured during the detector manufacturing process.

9. A reactor measuring coil segmented rod position detector measuring method according to claim 8, characterized in that: The calculation formula for the control rod position corresponding to each measuring coil in step 5 is as follows: Where N = 1, 2, 3, 4, ..., h N is the length of the control rod passing through the Nth coil, k N1 k is the influence coefficient of the impedance of the Nth measurement coil, N2 is the compensation coefficient of the Nth temperature compensation coil, u2 is the power supply voltage of the measuring coil, i NL Measure the coil current value for the Nth segment.

10. A reactor measuring coil segmented rod position detector measuring method according to claim 9, characterized in that: The calculation formula for the total control rod position in step 6 is as follows: h=h1+h2+……+h N Where h is the total length of the control rods.

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