Reactor redundancy coding detection type safety level rod position detector and measuring method

Abstract

The invention relates to the technical field of nuclear power station control rod position measurement, in particular to a reactor redundancy coding detection type safety level rod position detector and a measurement method, and the detector comprises a rod position processing device, and a first rod position measurement device and a second rod position measurement device which are electrically connected with the rod position processing device; the rod position detection equipment comprises a rod position detector, a first primary winding, a first auxiliary winding, a first secondary winding, a second primary winding, a second auxiliary winding and a second secondary winding; the first primary winding, the first auxiliary winding and the first secondary winding are electrically connected with the first rod position measuring equipment; and the second primary winding, the second auxiliary winding and the second secondary winding are electrically connected with the second rod position measuring equipment. According to the invention, through the arrangement of redundant rod position measuring equipment and related windings, the problem that the measuring rod position of one quadrant in the reactor core is unavailable when a single row of rod position measuring equipment fails is avoided.

Description

Technical Field

[0001] The invention relates to the technical field of nuclear power plant control rod position measurement, and in particular to a reactor redundant coding detection type safety-level rod position detector and a measurement method. Background Art

[0002] The control rod position system of a nuclear power plant reactor is used to lift, insert and hold the control rod bundle, and monitor the position of each control rod bundle. The coded detection detector system provides an excitation signal to the primary side of the rod position detector, and collects the feedback signal of the secondary winding at the same time. After processing by filtering, shaping, etc., the rod position code is finally formed. Different rod position codes represent different positions of the control rod bundle.

[0003] At present, except for the EPR reactor type (the third generation nuclear power reactor proposed by Europe), the rod position system in nuclear power plants of other reactor types is a non-safety level system. Although the rod position system of the EPR reactor type is a safety level system, it does not comprehensively consider the accident of single rod dropping or single rod lifting. The failure of a single column measurement system will cause the measurement rod position of one quadrant in the core to be unavailable, which will seriously affect the calculation accuracy of the protection parameters and lead to large uncertainty in the calculation of the system. For safety reasons, the operation margin of the envelope calculation uncertainty needs to be preset during the design, which leads to a relatively small safe operation range of the unit and a relatively low economic efficiency of the nuclear power plant operation. Summary of the invention

[0004] The object of the present invention is to provide a reactor redundant coding detection type safety level rod position detector and a measuring method, which are used to solve the problem that a single row measurement system failure may cause the measurement rod position of a quadrant in the core to be unavailable.

[0005] The embodiments of the present invention are implemented by the following technical solutions:

[0006] In a first aspect, a reactor redundant coding detection type safety level rod position detector is provided, comprising a rod position processing device and a first rod position measuring device and a second rod position measuring device electrically connected thereto;

[0007] A rod position detection device, the rod position detection device comprising a rod position detector, a first primary winding, a first auxiliary winding, a first secondary winding, a second primary winding, a second auxiliary winding and a second secondary winding;

[0008] The first primary winding, the first auxiliary winding and the first secondary winding are all electrically connected to the first rod position measuring device; the second primary winding, the second auxiliary winding and the second secondary winding are all electrically connected to the second rod position measuring device;

[0009] The first primary winding and the second primary winding are each evenly wound on the rod position detector; the first auxiliary winding is composed of two coils connected in series and arranged at the upper and lower ends of the first primary winding, and the second auxiliary winding is composed of two coils connected in series and respectively wound at the upper and lower ends of the second primary winding; the first secondary winding and the second secondary winding are both composed of multiple coils, each evenly spaced apart, wound on the rod position detector.

[0010] Furthermore, the first secondary winding and the second secondary winding are both composed of multiple coils, the number of coils in each secondary winding is the same, and the multiple coils in each secondary winding are further combined into multiple coil groups; the coils in the first secondary winding are spaced apart by a second preset length, the coils in the second secondary winding are spaced apart by a second preset length, the coils in two adjacent first secondary windings are spaced apart by a coil in the second secondary winding, and the coils in the first secondary winding are spaced apart from the coils in the adjacent second secondary winding by a first preset length.

[0011] Furthermore, the first preset length is 6 unit lengths, and the second preset length is 12 unit lengths.

[0012] Furthermore, the first secondary winding and the second secondary winding each include 21 coils.

[0013] Further, the multiple coil groups are specifically 5 coil groups, wherein the first coil group includes 11 coils, the second coil group includes 5 coils, the third coil group includes 3 coils, and the fourth coil group and the fifth coil group each include 1 coil;

[0014] Each coil in a coil group having a plurality of coils in each secondary winding is connected in series in sequence;

[0015] One end of each coil group of each secondary winding is connected in parallel to the ground, and the other end is electrically connected to the rod position measuring device.

[0016] In a second aspect, a reactor redundant coding detection type safety level rod position measurement method is provided, comprising the following steps:

[0017] Power is supplied to the primary winding connected to the rod position measuring device through the rod position measuring device;

[0018] collecting voltages of the first secondary winding and the second secondary winding;

[0019] Obtaining Gray code information representing the rod position information through the voltage of the first secondary winding and the second secondary winding;

[0020] Feedback the gray code information to the rod position processing device and obtain the rod position information.

[0021] Furthermore, it also includes:

[0022] The voltage of the primary winding and its corresponding auxiliary winding is collected for detection by the rod position measurement device; when the voltages of the primary winding, auxiliary winding and secondary winding in the detected channel are all lower than the preset voltage threshold, the rod position measurement device starts powering the detected primary winding.

[0023] Furthermore, the step of obtaining Gray code information representing the rod position through the voltage of the first secondary winding and the second secondary winding specifically includes:

[0024] The rod position measurement device converts the secondary winding voltage signal it obtains into an envelope curve through low-pass filtering;

[0025] Then the envelope curve is smoothed by sliding window average value filtering to obtain a smooth envelope curve;

[0026] The rod position information in the smooth envelope curve is then compared with the preset rod position threshold. If it exceeds the preset rod position threshold, a logic signal 1 is generated. If it is lower than the preset rod position threshold, a logic signal 0 is generated. Based on the comparison result, the corresponding Gray code is generated.

[0027] Furthermore, it also includes:

[0028] The rod position measuring device generates a quality bit indicating whether the rod position measuring device is abnormal through self-diagnosis, and feeds back the quality bit information to the rod position processing device;

[0029] The quality bit takes a value of 1 or 0, where 1 indicates normal and 0 indicates abnormal.

[0030] Furthermore, the obtaining of the rod position information specifically includes:

[0031] Determine the quality position information of two sets of rod position measuring devices;

[0032] If the quality bits of the two sets of rod position measurement devices are both 1, the full-precision rod position information is obtained;

[0033] If the quality bit of one set of rod position measurement devices is 1 and the quality bit of another set of rod position measurement devices is 0, then half-precision rod position information is obtained.

[0034] The technical solution of the embodiment of the present invention has at least the following advantages and beneficial effects:

[0035] The present invention avoids the problem of unavailability of measuring rod positions in one quadrant of the core due to failure of a single-row rod position measuring device by setting up redundant rod position measuring equipment and related windings; makes the measuring rod positions in all quadrants available, thereby ensuring the confidence of the rod position measurement; and the winding redundancy setting in the present application can obtain higher rod position measurement accuracy when both columns of windings are normal. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 A schematic diagram of the structure of a detector provided in Example 1 of the present invention;

[0037] Figure 2 A schematic diagram of the winding method of each winding provided in Embodiment 1 of the present invention;

[0038] Figure 3 A signal processing flow chart of each coil group of the secondary winding provided in Embodiment 2 of the present invention;

[0039] Figure 4 A schematic diagram of the half-precision bar-bit Gray code encoding rules provided in Example 2 of the present invention. DETAILED DESCRIPTION

[0040] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0041] The control rod position system of a nuclear power plant reactor is used to lift, insert and hold the control rod bundle, and monitor the position of each control rod bundle. The acquisition of the rod position is particularly important for the control of the reactor.

[0042] However, the existing method of using a single-row measurement system to obtain the rod position will cause the measurement rod position of one quadrant in the core to be unavailable when the single-row measurement system fails, which will seriously affect the calculation accuracy of the protection parameters and lead to a large system calculation uncertainty. Therefore, for safety reasons, it is necessary to preset an operating margin for the envelope calculation uncertainty during design, which leads to a relatively small safe operation range of the unit and a relatively low economic efficiency of nuclear power plant operation.

[0043] The present invention is proposed to solve the above problem, so as to make the rod position measurement of all quadrants available, thereby increasing the safe operation range of the unit. For specific implementation schemes, please refer to the description of the following embodiments.

[0044] Example 1

[0045] like Figure 1 As shown, this embodiment provides a reactor redundant coding detection type safety-level rod position detector, which includes a rod position processing device and a first rod position measuring device and a second rod position measuring device electrically connected thereto.

[0046] It also includes a rod position detection device, which includes a rod position detector, a first primary winding, a first auxiliary winding, a first secondary winding, a second primary winding, a second auxiliary winding and a second secondary winding; wherein the first primary winding, the first auxiliary winding and the first secondary winding are all electrically connected to the first rod position measuring device; the second primary winding, the second auxiliary winding and the second secondary winding are all electrically connected to the second rod position measuring device.

[0047] It can be seen that in this embodiment, two columns of rod position measurement systems are included, each of which includes a rod position measurement device and a plurality of windings corresponding to the rod position measurement device.

[0048] The relationship between each winding and the rod position detector is as follows:

[0049] The first primary winding and the second primary winding are each evenly wound on the rod position detector; the first secondary winding and the second secondary winding are each evenly wound on the rod position detector by a plurality of coils.

[0050] To facilitate understanding of the scheme, it should be noted that the rod position detector is a hollow tube, in which the control rod in the reactor is located. When the primary coil wrapped around the hollow tube is energized, a magnetic field is generated. When the position of the control rod changes, the magnetic field changes. At this time, the electromotive force in the secondary coil also changes, and the rod position information is obtained based on the current voltage signal of the secondary coil.

[0051] The first auxiliary winding is composed of two coils connected in series and respectively wound at the upper and lower ends of the first primary winding. The second auxiliary winding is composed of two coils connected in series and respectively wound at the upper and lower ends of the second primary winding.

[0052] In this embodiment, the first preset length is 6 unit lengths, each unit length is one mechanical step, and the length of each mechanical step is 15.875 mm.

[0053] Furthermore, the first secondary winding and the second secondary winding are both composed of a plurality of coils, the number of coils in each secondary winding is the same, in this embodiment, the number of coils is 21, and the plurality of coils in each secondary winding are further combined into a plurality of coil groups, for example, 5 groups; each coil in the first secondary winding is spaced apart by a second preset length, each coil in the second secondary winding is spaced apart by a second preset length, the coils in two adjacent first secondary windings are spaced apart by a coil in the second secondary winding, and the coil in the first secondary winding is spaced apart from the coil in the adjacent second secondary winding by the first preset length. The second preset length is 12 unit lengths, i.e., 12 mechanical steps.

[0054] In this embodiment, 21 coils are combined into 5 coil groups; wherein the first coil group includes 11 coils, the second coil group includes 5 coils, the third coil group includes 3 coils, and the fourth coil group and the fifth coil group each include 1 coil.

[0055] The coils in the coil group with multiple coils in each secondary winding are connected in series in sequence; that is, the coils in the first coil group, the second coil group and the third coil group are connected in series in sequence; one end of the five coil groups is connected in parallel and then grounded, and the other ends are respectively electrically connected to the rod position measurement equipment and independently output voltage signals, thereby obtaining five groups of electrical signals, so the number of shaping bits of the Gray code obtained subsequently is 5.

[0056] More specifically, the implementation of the safety-level rod position measurement in this embodiment is based on a redundant coded rod position detector with dual primary windings, dual auxiliary windings, and dual secondary windings.

[0057] The winding condition of the detector is as follows Figure 2 As shown, it is composed of two columns A and B of primary, auxiliary and secondary windings, and both columns of primary windings evenly cover the entire detection range of the rod position detector. It should be noted that the column A primary windings, column A auxiliary windings and column A secondary windings in this embodiment correspond to the first primary winding, the first auxiliary winding and the first secondary winding; the column B primary windings, column B auxiliary windings and column B secondary windings correspond to the second primary winding, the second auxiliary winding and the second secondary winding.

[0058] The auxiliary winding is arranged at both ends of the primary winding and is also divided into two columns, A and B. Each column of auxiliary winding is composed of two coils wound in series at the upper and lower ends of the primary winding, and the coil sections in the two columns of auxiliary winding are staggered by 6 mechanical steps, and the length of one mechanical step is 15.875mm.

[0059] The secondary winding is composed of 42 coils evenly wound, and each coil is separated by 6 mechanical steps. The secondary winding is also classified into two columns, A and B. Each column contains 21 coils, and the 21 coils are divided into 5 coil groups. The coils in each coil group are connected in series in positive and negative directions in turn, that is, the taps of two adjacent coils in each coil group are connected in positive and negative directions; one end of the five coil groups in each column are connected in parallel and then grounded, and the other end is electrically connected to the corresponding rod position measurement equipment, so that 5 groups of signals can be output.

[0060] Among them, Figure 2 As shown, in the secondary winding,

[0061] A row E group coils include: 31;

[0062] A row D group coils include: 15;

[0063] Coils in row A, group C include: 7, 23, 39;

[0064] Coils in row A, group B include: 3, 11, 19, 27, 35;

[0065] Coils in group A of row A include: 1, 5, 9, 13, 17, 21, 25, 29, 33, 37, 41;

[0066] Coils of group E in row B include: 32;

[0067] The coils of row B and group D include: 16;

[0068] Coils in row B, group C include: 8, 24, 40;

[0069] Coils in row B, group B include: 4, 12, 20, 28, 36;

[0070] Coils in group A of column B: 2, 6, 10, 14, 18, 22, 26, 30, 34, 38, 42.

[0071] The above-mentioned group A corresponds to the first coil group, group B corresponds to the second coil group, group C corresponds to the third coil group, group D corresponds to the fourth coil group, and group E corresponds to the fifth coil group.

[0072] From the above grouping, we can see that the interval between each coil in a single-row secondary winding is 12 mechanical steps, that is, the rod position measurement accuracy (resolution) is 12 steps when a single row is working. From the overall point of view, the coil interval is 6 mechanical steps, that is, the rod position measurement accuracy (resolution) is 6 steps when two rows are working at the same time.

[0073] Another example Figure 2 As shown, the zero position of the measuring rod is designed in the second coil of the secondary winding, so as to avoid the driving rod passing through the first coil. The first coil has edge leakage magnetic effect, and avoiding this coil can improve the rod position measurement accuracy.

[0074] In addition, if all coils in the secondary winding on the rod position detector are evenly spaced, the calibration interval of coil 3 is [0,12), which will cause a problem, that is, when the control rod is in the mechanical zero position, the measured rod position of the control rod cannot be guaranteed to be 0, and may be 3 (Mn_A=6, Mn_B=0). This error message will cause great trouble to the normal operation of the main control room. To avoid this situation, the design moves coil 3 back by 3 mechanical steps, at the expense of the optimal rod position effect, to ensure that the measured rod position of the control rod is 0 when the control rod is in the mechanical zero position.

[0075] like Figure 1 As shown, the topology of the rod position detector of a single-beam control rod is composed of a rod position detection device, two rod position measurement devices and a rod position processing device.

[0076] Among them, the main functions of the rod position measurement equipment are as follows:

[0077] Supply power to the single-row primary winding in the rod position detection device and provide an excitation signal;

[0078] Detect the voltages of the primary winding, the auxiliary winding, and the secondary winding, and perform primary power supply switching control for columns A and B; for the specific switching control principle, please refer to the method description in Example 2;

[0079] Collect the single-row secondary winding voltage signal in the rod position detection device, process and calculate the single-row rod position (half-precision);

[0080] The quality position of the rod position measurement in this column is determined and sent together with the semi-precision rod position to the rod position processing device through network communication.

[0081] The main functions of the rod handling equipment are as follows:

[0082] Receive the half-precision rod position with quality position sent by the rod position measuring devices of the two columns A and B;

[0083] Fit the half-precision rod positions (with quality positions) of columns A and B into full-precision rod positions;

[0084] When the A or B single-row rod position fails, the full-precision rod position automatically switches to the half-precision rod position.

[0085] Based on the above structural features, the wiring and measurement principles of the two-row rod position measurement device structure in this embodiment to achieve independent measurement are as follows:

[0086] like Figure 1 As shown, the rod position measurement devices in the two columns A and B are electrically connected to the corresponding windings on the rod position detector, that is, the primary excitation signal output interface, the auxiliary voltage detection interface, and the secondary voltage acquisition interface are respectively connected to the interfaces of the primary winding, the auxiliary winding, and the secondary winding on the rod position detector, thereby forming the rod position measurement channels in the two columns A and B. The power supplies (control power and primary power supply) of the two columns of rod position measurement devices are independently powered. At the same time, the windings in the two columns A and B on the rod position detector have sufficiently high insulation performance to ensure the electrical isolation of the rod position measurement channels in the two columns A and B and independently execute the rod position measurement function, so as to achieve no signal interaction between them.

[0087] Independent measurement principle: The rod position measurement equipment of one of the two columns A and B applies AC power excitation to the corresponding primary winding, thereby generating a magnetic field inside the detector. This magnetic field generates induced voltages in the auxiliary windings and secondary windings of the two columns. The rod position measurement equipment of the two columns simultaneously collects the secondary winding voltages of their respective columns and processes them into Gray code signals that characterize the rod position. The key point of independent measurement is that at the same time, only one power supply of the two columns of primary windings is valid. Under normal circumstances, it is powered by column A. When the power supply of the primary winding of column A is abnormal, it is automatically switched to the primary winding of column B for power supply. In this way, an abnormality in a single column measurement channel will not affect the rod position measurement of another column.

[0088] Based on the structure in this embodiment, it can be known that the redundant rod position measurement equipment and the related winding settings can avoid the problem of unavailability of the measurement rod position in one quadrant of the core when a single-column rod position measurement equipment fails; the measurement rod positions in all quadrants are available, thereby ensuring the confidence of the rod position measurement; and the winding redundancy setting in this application can obtain higher rod position measurement accuracy when both columns of windings are normal. It should be emphasized that in the redundant setting here, no matter which group of primary windings is excited, the two groups of secondary windings and the two groups of auxiliary coils can obtain voltage information.

[0089] Example 2

[0090] This embodiment mainly describes in detail a reactor redundant coding detection type safety level rod position measurement method, which includes the following steps:

[0091] Power is supplied to the primary winding connected to the rod position measuring device through a rod position measuring device; after the primary winding wound on the rod position detector is excited, a magnetic field is generated, which in turn generates an induced electromotive force in the auxiliary winding and the secondary winding. Therefore, the rod position measuring device can obtain the voltage signals output by each column of the auxiliary winding and the secondary winding.

[0092] The voltages of the first secondary winding and the second secondary winding are collected; and the Gray code information representing the rod position information is obtained through the voltages of the first secondary winding and the second secondary winding; specifically: the rod position measurement device converts the acquired secondary winding voltage signal into an envelope curve through low-pass filtering; then the envelope curve is smoothed by sliding window average value filtering to obtain a smoothed envelope curve; then the rod position information in the smoothed envelope curve is compared with a preset rod position threshold, if it exceeds the preset rod position threshold, a logic signal 1 is generated, if it is lower than the preset rod position threshold, a logic signal 0 is generated, and based on the comparison result, a corresponding Gray code is generated.

[0093] In the specific implementation, Figure 3 As shown, the original signal fed back by the secondary winding is a sinusoidal signal of an AC transformer voltage. After the rod position measurement device collects the original signal, it first converts the original waveform into its envelope curve through low-pass filtering, and then smoothes the envelope curve through sliding window average filtering. The smoothed envelope curve is compared with the preset rod position threshold through a comparator. If the value exceeds the threshold, a logic "1" signal is generated; if it is lower than the threshold, a logic "0" signal is generated, thereby obtaining a Gray code with a shaping bit number of 5, and different Gray codes represent different rod position values; the reason why the shaping bit number of the Gray code is 5 is that each column of the secondary winding is divided into 5 coil groups, and the voltage signal output by each coil group is a Gray code on a digit.

[0094] Combination Figure 2 and Figure 4It can be seen that each coil of the secondary winding corresponds to a detection interval; it can be understood that when the top of the control rod approaches a coil (that is, the top of the control rod enters the detection interval of a coil), the magnetic field near the coil will change, and the magnetic field change will cause the coil induced voltage to change. The goal of the rod position measurement is to obtain the voltage change characteristics, and based on the voltage change characteristics, the Gray code change of the digit belonging to the coil is obtained, which corresponds to the rod position value change. Therefore, the rod position value will change once within the detection interval of the coil.

[0095] In a specific implementation, the half-precision rod position encoding of the two columns of rod position measurement channels is as follows: Figure 4 shown.

[0096] Assuming that the control rod driving rod is located between the nth (n≥2) coil and the n+1th coil, the coil here refers to the coil in the secondary winding. At this time, the measurement rod position Mn of the A and B columns can be expressed as:

[0097] When n is an odd number:

[0098] Mn_A=(n-1) / 2×12-6

[0099] Mn_B=(n-1) / 2×12

[0100] When n is an even number:

[0101] Mn_A=n / 2×12-6

[0102] Mn_B=(n / 2-1)×12

[0103] In summary:

[0104] The scales of the measuring rods in column A are 0, 6, 18, 30, 42···234;

[0105] The scales on the measuring rods in column B are = 0, 12, 24, 36, 48···240.

[0106] In order to determine whether the current measurement accuracy should adopt full precision or half precision, the method also includes obtaining the quality position of the rod position measurement device. The specific implementation is as follows:

[0107] The rod position measuring device generates a quality bit indicating whether the rod position measuring device is abnormal through self-diagnosis, and feeds back the quality bit information to the rod position processing device;

[0108] The quality bit takes a value of 1 or 0, where 1 indicates normal and 0 indicates abnormal.

[0109] Specifically, the rod position measurement device determines the quality bit of the rod position in this column through the diagnostic mechanism, and sends it unidirectionally to the rod position processing device together with the semi-precision rod position signal of this column. The quality bit represents the working / abnormal status of the rod position measurement channel in this column, where 1 represents normal and 0 represents abnormal. The confidence level of the quality bit depends on the completeness of the diagnostic mechanism of the rod position measurement device. To achieve the best effect, in theory, the rod position measurement device needs to be able to diagnose the status of all sub-modules of the entire rod position measurement channel, including the working status of the electronic devices, the wiring status, the electrical characteristics of the rod position detector, whether the rod position changes are normal, etc.; if there is an abnormality in the above status, the quality bit is 0.

[0110] It should be noted that the above-mentioned abnormality diagnosis mechanism can adopt the relevant diagnosis mechanism of existing equipment, and the present invention does not involve improvement of the diagnosis mechanism.

[0111] The gray code information obtained above and its corresponding quality bit information are fed back to the rod position processing device, and the rod position information is obtained.

[0112] Among them, obtaining the stick position information specifically includes:

[0113] Determine the quality position information of two sets of rod position measuring devices;

[0114] If the quality bits of the two sets of rod position measurement devices are both 1, the full-precision rod position information is obtained;

[0115] If the quality bit of one set of rod position measurement devices is 1 and the quality bit of another set of rod position measurement devices is 0, then half-precision rod position information is obtained.

[0116] Under normal circumstances, the quality bits of both groups will not be 0, because the two groups of rod position measurement channels are redundantly set. When one of the quality bits is 0, maintenance will be carried out in a timely manner. The redundant setting in this application can ensure that even if one group of rod position measurement equipment fails, semi-precision rod position information can still be obtained, so that the reactor can still operate normally.

[0117] Specifically, when the rod position processing device receives the quality position αA or αB of 0 from the rod position measuring devices of columns A and B, it means that the rod position of single column A or B is invalid, and the rod position will eventually switch automatically from full precision to half precision.

[0118] That is, when αA=0, αB=1: Mn=Mn_B;

[0119] When αA=1, αB=0: Mn=Mn_A.

[0120] When αA=1, αB=1, the final rod position Mn is fitted. The specific fitting method is as follows:

[0121] Mn=(Mn_A+Mn_B) / 2=(n-1) / 2×6-3

[0122] At this time, the accuracy of the final rod position can reach ±6 mechanical steps. At this time, the final measuring rod position scale is 0, 3, 9, 15, 21···237, and the measuring rod position of each scale is located at the center of its calibration interval, which can achieve the optimal rod position measurement effect.

[0123] In addition, the method also includes a switching mechanism for power supply excitation of two columns of primary windings, that is, collecting the voltage of the primary winding and its corresponding auxiliary winding for detection by the rod position measurement device; when the voltage of the detected primary winding and its corresponding auxiliary winding and secondary winding are all lower than the preset voltage threshold, the rod position measurement device starts powering the detected primary winding.

[0124] Specifically, the implementation principle of the automatic switching mechanism of the primary excitation of the A and B columns is as follows: the rod position measurement equipment of the A and B columns respectively detects the primary winding, auxiliary winding voltage and secondary winding coil voltage; when the primary winding voltage is detected to be lower than the set threshold, it indicates that the primary power supply of the column is in a lost state; when the auxiliary winding voltage is detected to be lower than the set threshold, it indicates that the rod position detector has no primary excitation or the auxiliary winding of this column is abnormal; when the secondary winding coil voltage is detected to be lower than the set threshold, it indicates that the rod position detector has no primary excitation or the secondary winding coil of this column is abnormal; in summary, when a single column detects that the primary winding, auxiliary winding voltage and secondary winding voltage are all lower than their set thresholds, according to the single fault principle, it can be concluded that the rod position measuring device has no primary excitation and is caused by the abnormal primary power supply of another column. At this time, turn on the primary power supply of this column to restore normal rod position measurement.

[0125] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A reactor redundant coding detection type safety level rod position detector, characterized in that: It includes a rod position processing device and a first rod position measuring device and a second rod position measuring device electrically connected thereto; A rod position detection device, the rod position detection device comprising a rod position detector, a first primary winding, a first auxiliary winding, a first secondary winding, a second primary winding, a second auxiliary winding and a second secondary winding; The first primary winding, the first auxiliary winding and the first secondary winding are all electrically connected to the first rod position measuring device; the second primary winding, the second auxiliary winding and the second secondary winding are all electrically connected to the second rod position measuring device; The first primary winding and the second primary winding are each evenly wound on the rod position detector; the first auxiliary winding is composed of two coils connected in series and respectively wound at both ends of the first primary winding, and the second auxiliary winding is composed of two coils connected in series and respectively wound at both ends of the second primary winding; the first secondary winding and the second secondary winding are each evenly wound on the rod position detector.

2. The reactor redundant coding detection type safety level rod position detector according to claim 1, characterized in that: The first secondary winding and the second secondary winding are both composed of multiple coils, the number of coils in each secondary winding is the same, and the multiple coils in each secondary winding are further combined into multiple coil groups; the coils in the first secondary winding are spaced apart by a second preset length, the coils in the second secondary winding are spaced apart by a second preset length, the coils in two adjacent first secondary windings are spaced apart by a coil in the second secondary winding, and the coils in the first secondary winding are spaced apart from the coils in the adjacent second secondary winding by the first preset length.

3. The reactor redundant coding detection type safety level rod position detector according to claim 2, characterized in that: The first preset length is 6 unit lengths, and the second preset length is 12 unit lengths.

4. The reactor redundant coding detection type safety level rod position detector according to claim 2, characterized in that: The first secondary winding and the second secondary winding each include 21 coils.

5. The reactor redundant coding detection type safety level rod position detector according to claim 4, characterized in that: The multiple coil groups are specifically 5 coil groups, wherein the first coil group includes 11 coils, the second coil group includes 5 coils, the third coil group includes 3 coils, and the fourth coil group and the fifth coil group each include 1 coil; Each coil in a coil group having a plurality of coils in each secondary winding is connected in series in sequence; One end of each coil group of each secondary winding is connected in parallel to the ground, and the other end is electrically connected to the rod position measuring device.

6. A reactor redundant coding detection type safety level rod position measurement method, characterized in that: The steps include: Power is supplied to the primary winding connected to the rod position measuring device through the rod position measuring device; collecting voltages of the first secondary winding and the second secondary winding; Obtaining Gray code information representing the rod position information through the voltage of the first secondary winding and the second secondary winding; Feedback the gray code information to the rod position processing device and obtain the rod position information.

7. The reactor redundant coding detection type safety level rod position measurement method as claimed in claim 6, characterized in that: Also includes: The voltage of the primary winding and its corresponding auxiliary winding is collected for detection by the rod position measurement device; when the voltages of the primary winding, auxiliary winding and secondary winding in the detected channel are all lower than the preset voltage threshold, the rod position measurement device starts powering the detected primary winding.

8. The reactor redundant coding detection type safety level rod position measurement method as claimed in claim 6, characterized in that: The step of obtaining the gray code information representing the rod position through the voltage of the first secondary winding and the second secondary winding specifically includes: The rod position measurement device converts the secondary winding voltage signal it obtains into an envelope curve through low-pass filtering; Then the envelope curve is smoothed by sliding window average value filtering to obtain a smooth envelope curve; The rod position information in the smooth envelope curve is then compared with the preset rod position threshold. If it exceeds the preset rod position threshold, a logic signal 1 is generated. If it is lower than the preset rod position threshold, a logic signal 0 is generated. Based on the comparison result, the corresponding Gray code is generated.

9. The reactor redundant coding detection type safety level rod position measurement method as claimed in claim 6, characterized in that: Also includes: The rod position measuring device generates a quality position indicating whether the rod position measuring device is abnormal through self-diagnosis, and feeds back the quality position information to the rod position processing device; The quality bit takes a value of 1 or 0, where 1 indicates normal and 0 indicates abnormal.

10. The reactor redundant coding detection type safety level rod position measurement method as claimed in claim 9, characterized in that: The obtaining of the rod position information specifically includes: Determine the quality position information of two sets of rod position measuring devices; If the quality bits of the two sets of rod position measurement devices are both 1, the full-precision rod position information is obtained; If the quality bit of one set of rod position measurement devices is 1 and the quality bit of another set of rod position measurement devices is 0, then half-precision rod position information is obtained.

Images