Control and protection method of fast neutron nuclear reactor and implementation system thereof

Abstract

The invention relates to the field of nuclear power, in particular to a control method of a nuclear reactor, which is mainly used for a fast neutron nuclear reactor which is long in operation time and has a single value relationship between fuel burn-up reactivity margin and a reactor power generation value, and an absorption rod arranged in a reactor core can compensate the reactivity margin and execute other functions of a control and protection system. The absorber rod is moved in an automatic power conditioner operating mode according to the position calculation of the absorber rod, so as to control the nuclear reactor, and the position of the absorber rod ensures that the optimal shape of the energy release field is realized for each motion (power generation).

Description

Technical Field

[0001] The present invention relates to the field of nuclear power, and specifically to a control method for a nuclear reactor (NR), which is mainly used for fast neutron nuclear reactors with long movement time, a single-value relationship between fuel burnup reactivity margin and reactor power generation value, and an absorber rod (AR) arranged in the core can compensate for the reactivity margin and perform other functions of the control and protection system (CPS). Among them, the single-value relationship between the fuel burnup reactivity margin and the reactor power generation value in a strict sense is intended to be used for the set power output chart and the movement algorithm of the absorber rod of the control and protection system to compensate for fuel burnup, reactivity power and temperature efficiency, and to perform operating power control (such as reactor operating power control in basic power generation mode). For fast neutron reactors, if there is a deviation from the set power output chart when setting power generation, it will not cause obvious deviations in the relationship between the fuel burnup reactivity margin and the reactor power generation value, because these deviations are significantly lower than the fuel burnup reactivity margin. Background Art

[0002] It is well known that in order to improve the technical and economic index, the energy release field of the reactor must be distributed to ensure that the core elements operate under the most favorable temperature conditions. This can be achieved, for example, by physically analyzing the fuel load of the nuclear reactor core and using different uranium enrichments in different radiation zones.

[0003] However, during the operation of the reactor, the original distribution of the energy release field may change due to different fuel burnup. This is very important for nuclear reactors without partial overloading / rearrangement of fuel assemblies, if the fuel moves for a long time. Therefore, in such nuclear reactors, absorber rods arranged in the core can be used as auxiliary devices for uniform distribution of the coolant temperature at the core outlet during fuel operation, which can control the neutron power of the reactor and compensate for the burnup reactivity margin. To this end, during the combustion process, the absorber rods arranged in the areas of the core where the heat release needs to be increased are first removed, and then the absorber rods arranged in the areas of the core where the energy release needs to be reduced are removed (M.A. Schulitz, Regulation of Nuclear Reactors, Foreign Literature Publishing House, Moscow, 1957).

[0004] For nuclear reactors with partial fuel overload, the above problem is not so urgent, because in such nuclear reactors, the fuel overload situation can also be used to effectively influence the distribution of the energy release field.

[0005] In the case of reactors with a large number of absorber rods, it is most possible to influence the energy release field using the absorber rod control algorithm. These absorber rods perform the functions of reactivity margin compensation, automatic power regulation and emergency protection (EP) and have a unified actuator (ACT), similar to the actuator of the control and protection system (CPS) of the nuclear reactor VVER-1000 (CPS VVER-1000). In such reactors, the movement sequence of the group of CPS absorber rods in the core is loaded into the program control system of the CPS absorber rods, and the group of CPS absorber rods in the core is symmetrically arranged at different radii. However, in the VVER-1000 reactor, due to the use of the secondary (primary) compensation system of the reactivity margin of the burnup, that is, the addition of boric acid to the coolant, in the energy mode of reactor operation, almost all the CPS absorber rods are moved from the core to the top, without affecting the distribution of the energy release field.

[0006] In patent application US4717528A, a control system for regulating rods of a nuclear reactor is provided, which can control the energy release distribution in the core. The control system includes a computing device for calculating the efficiency difference of the absorber rods and the energy release field in the nuclear reactor, controlling the burnup distribution, reducing the local power, and forming an absorber rod movement strategy, which can minimize the non-uniformity of energy release and fuel burnup in the core. However, for a pressurized water reactor (PWR), when this scheme is adopted, the impact on the energy release field is very limited because its burnup reactivity margin is compensated by adding boric acid to the coolant.

[0007] In the international application WO2020 / 224764, a control method for a PWR reactor is provided, in which the operation algorithm of the reactor power influencing elements (absorber rods, boric acid solution filling pipes) is calculated based on the load diagram provided by the dispatcher 24 hours ago and a series of restrictions on reactor parameters (minimizing absorber rod movement, maintaining the required axial offset value, minimizing boric acid and distilled water consumption, fuel consumption compensation, fuel consumption balance, etc.). During the operation of the reactor, the control mechanism is used to directly calculate several options that affect the reactor, and the most suitable option is selected from the options that meet the selected criteria. This patent can be regarded as similar to this patent.

[0008] This reactor control method can control the energy release field, etc. In this patent, the movement algorithm of the absorber rod is calculated in real time. This is because, in thermal neutron reactors, especially PWR reactors, the acid corrosion phenomenon is very typical and has a complex time (iodine well) and space (xenon wave) relationship, which is determined by the power change history of the reactor in the past few days. Therefore, it is impossible to calculate the optimal loading shape of the absorber rod of the thermal neutron reactor in advance at the design stage.

[0009] The main shortcomings of the technical solution provided by this similar patent are:

[0010] 1. The energy release field cannot be formed in the best way, because while moving the absorption rods, other important tasks need to be solved: ensuring a negative offset value to eliminate the heat exchange crisis and compensating for the xenon oscillations in the neutron flux distribution and the resulting energy release. These requirements may be contradictory.

[0011] Xenon oscillations in high-power tubular reactors always required manual intervention by operators before the introduction of local automatic power regulators when the reactors were operated at constant power. In PWR reactors / VVER type power reactors, there are no local automatic power regulators.

[0012] 2. The online calculation results of various functions are updated in a cycle of 200 milliseconds, which requires simplifying the algorithm and preventing the use of the most accurate calculation methods with high machine time costs, even when offline calculations are used during the design phase.

[0013] 3. If a PWR reactor / VVER type power reactor is operated at a constant power for a long time, due to burnup, the reactivity decreases, resulting in a mismatch between the set power and the actual power (the average temperature of the refrigerant or the steam pressure in the steam collector decreases), which will not cause a change in the position of the compensating rod, but will issue a request to reduce the boric acid concentration. The compensating rod can be taken out in different ways by controlling the energy release field, while if the boric acid concentration is too high, the energy release field cannot be controlled.

[0014] 4. The technical solution proposed in this patent is not suitable for fast reactors, because there is no xenon effect in fast reactors. Due to the decrease in fuel consumption reactivity, from the beginning of the movement to the end of the movement, before the absorber rods are completely removed from the core, it is necessary to remove the absorber rods from the maximum loading state, so as to effectively control the energy release field.

[0015] 5. In similar patents, there is no description of the technical algorithm for implementing the technical solution of this patent.

[0016] The technical solution provided by the present application is applicable to fast neutron reactors, there is no acid corrosion, the reactivity margin of the burnup is completely compensated by the absorber rods, and in water-cooled reactors, due to the possible heat removal crisis, it is necessary to ensure that the required offset is achieved, and the technical solution provided by the present application does not need to ensure that the required offset is achieved, so the present application does not have the shortcomings of the above-mentioned similar patents. Therefore, for each movement that can only be determined by power generation, the optimal position of the absorber rod can be most accurately calculated in the reactor design stage, which is only related to the fuel burnup, and the position of the absorber rod is provided for each movement of the fuel, and the optimal shape of the energy release field is provided, ensuring that the coolant temperature field at the core outlet can achieve maximum equilibrium, and it is loaded into the algorithm and hardware solution of the automatic control system in the design stage.

[0017] Abbreviations used:

[0018] EP: Emergency Protection

[0019] NFME: Neutron Flux Monitoring Equipment

[0020] APC: Automatic Power Controller

[0021] CB: Comparison component

[0022] PT: Position Sensor

[0023] PLS: Power Level Sensor

[0024] PS: Power valuer

[0025] ACT: Executive Agency

[0026] PM: Period Meter

[0027] CR: Compensation rod.

[0028] MCPL: Minimum Controllable Power Level

[0029] LLS: Bottom limit switch

[0030] SPM: Planned Preventive Maintenance

[0031] AR: Absorbent Rod

[0032] PCD: Program Control Device

[0033] S: Selector

[0034] CPS: Control and Protection System

[0035] EM: Electricity generation meter

[0036] E: Reactor power generation

[0037] NR: Nuclear Reactor Summary of the invention

[0038] The method and apparatus according to the present invention can solve the problem of increasing reactor power without increasing coolant flow.

[0039] The technical effect of the present invention is to increase the average temperature of the coolant at the core outlet, and to increase the power of the reactor accordingly by ensuring the dynamic shaping of the energy release field during the movement, but without increasing the coolant flow, thereby reducing the non-uniformity of the coolant temperature field at the core outlet. Another technical effect is that the maximum temperature of the fuel cladding can be reduced, thereby improving the operational reliability and safety, and while maintaining the average coolant temperature at the core outlet, the energy release field is balanced, thereby maintaining the power and movement time of the reactor.

[0040] To achieve the above technical effects, the present invention provides a method for automatically controlling the power of a fast neutron nuclear reactor by moving an absorption rod of an automatic power regulator, comprising:

[0041] - The position of the absorber rod is pre-calculated during the design phase to ensure that the energy release field has the optimal shape for each movement (generation);

[0042] - Based on the calculation results, a program with an absorber rod removal sequence is loaded into the memory of a program control device (PCD) so that the absorber rod is moved from the core along the radius of the core to a position corresponding to the optimal shape of the energy release field to achieve the set power generation value;

[0043] - opening the automatic power regulator (APC) to change the position of the absorbing rod according to the signal formed in the comparison element, which compares the difference between the signal output by the power valuer and the power level sensor, and the difference between the set period of the reactor in the start-up mode and the actual period from the period measuring device, wherein the signal is output from the neutron flux monitoring equipment (NFME) to the power level sensor and the period measuring device;

[0044] - place the reactor at a set energy power level corresponding to the inserted shape of the absorber rods, automatically remove the absorber rods or place them in the core at positions corresponding to the optimal energy release distribution in the order loaded into the memory of the program control device to ensure the optimal shape of the energy release field is achieved, and load the calculated results into the program control device, wherein the absorber rods are moved by the absorber rod actuator;

[0045] - supplying power to the absorber rods through the absorber rod selector, automatically moving the absorber rods into the core with small spacings in the order loaded into the memory of the program control device, the value of which ensures that the inserted shape of the absorber rods is not distorted, so that the cycle of the reactor is limited by the set value of the comparison element (CB) before the reactor reaches the critical state of the minimum controlled power level (MCPL), and when the program control device receives a signal from the comparison element that the set value of the minimum controlled power level has been reached, the removal of the absorber rods is stopped and then remains in automatic mode;

[0046] - subsequently, at the command of the operator, the power of the reactor is increased from the lowest controlled power level to a level corresponding to the beginning of the energy range set in the program control device (about 3-5% of the rated power), wherein the absorption rods operating in the automatic power regulator (APC) mode, according to the imbalance signal between the set power and the actual power level provided by the comparison element, supply power to the absorption rod actuator, the actuator extracts the absorption rod and introduces positive reactivity to the reactor, which ensures that the actuator automatically closes after the reactor power increase cycle set in the program control device;

[0047] - When the actual power level approaches the set power and negative feedback (slowing the rate of power increase) begins to work (reactor cycle increases), according to the imbalance signal between the set power and the actual power level provided by the comparison element, power is supplied to the absorption rods through the absorption rod selector, and the absorption rod actuator automatically takes out the absorption rods from the core at small intervals according to the sequence loaded into the memory of the program control device until the reactor reaches the power level set by the power setter (PS) to compensate for the reactive power effect, after which the last absorption rod operating in the automatic power regulator mode automatically maintains this power level;

[0048] - Subsequently, when the turbine unit is ready for operation, the reactor switches to the power level set by the power setter and automatically maintains this level, wherein, as the fuel is consumed, the absorber rods are taken out in a certain order according to the program loaded into the memory of the program control device and placed in positions that ensure the optimal shape of the energy release field (maximum balance of the coolant temperature field at the core outlet), and for each power generation, the relevant signal about the current power generation value is transmitted from the electric meter (EM) to the program control device.

[0049] The above technical effects are also achieved through an automatic power control system of a nuclear reactor, which includes: an absorption rod that acts on reactivity, a neutron flux monitoring device, a control device, multiple absorption rod position sensors and indicators, a power setter, a reactor cycle measuring device, a comparison element and an electric meter, wherein the absorption rod is provided with multiple actuators, each of which performs the functions of an automatic power regulator, a compensation rod and an emergency protection rod; the control device can form an early warning and emergency signal of the absorption rod position change; the comparison element can form a signal transmitted to the actuator; the actuator can affect the movement of the absorption rod; the control device includes a program control device for obtaining signals from power level sensors, electric meters and absorption rod position sensors, and transmitting the function of automatically controlling power from one absorption rod to another absorption rod through an absorption rod selector, so that the absorption rod moves during the movement, and the absorption rod system forms a certain loading shape according to the order loaded into the program control device and the absorption rod movement interval.

[0050] By using the device provided by the present invention to implement the method provided by the present invention, the non-uniformity of the coolant temperature field at the core outlet can be reduced, thereby increasing the average coolant temperature at the core outlet, and correspondingly increasing the power of the reactor without increasing the coolant flow rate of the primary circuit, and without exceeding the maximum allowable temperature of the fuel cladding. The present invention can also greatly reduce the workload of operators in manually controlling the nuclear reactor, thereby eliminating the impact of human factors on safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] The invention will be described below with reference to the accompanying drawing (FIG), which shows a block diagram of a possible embodiment of the device according to the invention. DETAILED DESCRIPTION

[0052] A control and protection system for a nuclear reactor comprises: an absorption rod 1 for acting on reactivity, a neutron flux monitoring device 3, a control device, an absorption rod 4 position sensor, a power valuer 5, a power level sensor 6, a reactor cycle measuring device 7, a comparison element 8 and an electric meter 9, wherein the absorption rod is provided with an actuator 2, each of which performs the functions of an automatic power regulator, a compensation rod and an emergency protection rod; the control device can form an early warning and emergency signal of the position change of the absorption rod 1; the comparison element can form a signal transmitted to the actuator 2, and the actuator can affect the movement of the absorption rod 1; the control device comprises a program control device 10, which is used to obtain signals from the power level sensor 6, the electric meter 9 and the absorption rod 4 position sensor, and transmit the function of automatically controlling power from one absorption rod 1 to another absorption rod 1 through an absorption rod selector 11, so that the absorption rod 1 moves during the movement, and according to the order loaded into the program control device 10 and the movement interval of the absorption rod 1, the absorption rod 1 system forms a certain loading shape.

[0053] In the control and protection system provided, in the automatic program control mode, all the absorption rods 1 are involved in the operation, and then perform the function of automatically changing and maintaining the set power level. The actuator 2 of the absorption rod 1 is used to automatically switch the position of the absorption rod, and its start signal is generated by the comparison element (CB) 8, which compares the signal difference output by the power setter (PS) and the power level sensor (PLS), and the signal difference between the set cycle of the reactor and the actual cycle from the cycle measurer (PM) in the start mode. The start signal is output from the neutron flux monitoring equipment (NFME) to the power level sensor and the cycle measurer. During the movement, the absorption rod 1 moves to the corresponding position according to the order loaded into the program control device (PCD), which ensures the realization of the optimal shape of the energy release field.

[0054] To this end, the absorption rods are set at different radii. When the reactor is operating at an energy power level, the absorption rods move in the core. Each time they move at a set power level, the position of the absorption rods in the core is determined by calculation, thereby ensuring that the optimal shape of the energy release field is achieved.

[0055] Before implementing the control method for dynamically controlling the energy release field, the reactor is placed at a set energy power level corresponding to the installed shape of the absorber rods 1, thereby ensuring that the optimal shape of the energy release field is achieved.

[0056] The following is one possible procedure for reaching a set energy power level, as an example.

[0057] The positions of the absorber rods are calculated using publicly available software, such as the REACTOR application package (O.G. Komelev, N.N. Novikova, M.M. Trievvoda, E.V. Firimonov, "Current Status and Problems of Software for Design and Development of Calculation Methods for Reactor Installations with Lead-Bismuth Coolants", University Press; "Nuclear Energy", 2007, No. 1, pp. 79-91), to ensure a balanced energy release field.

[0058] According to the calculation results, a program with the absorption rod removal sequence is loaded into the memory of the program control device, so that the absorption rods are moved from the core to a position corresponding to the optimal shape of the energy release field to achieve the set power generation value.

[0059] The reactor was started.

[0060] The first startup phase starts from the initial extinguishing state of the reactor. When all the absorber rods 1 are located at the lower limit switch, according to the command of "emergency protection start", the electromagnet winding of the actuator 2 is powered, wherein the electromagnet keeps the absorber rod 1 in the set position. Subsequently, the absorber rod 1 is powered by the absorber rod selector (S) 13 according to the program loaded into the memory of the program control device 10, and the absorber rod actuator 2 is used to automatically remove the absorber rod from the core and put it in the "flat" position with the same value, in accordance with the requirements of the normative technical documents, to ensure the subcriticality required for safety. This position of the absorber rod 1 is loaded into the memory of the program control device 10, determined in advance by calculation, and must be verified by experiment when the reactor is started for the first time with new fuel loaded.

[0061] The second startup phase starts with the "shape" command. According to the command, power is supplied to the absorption rod 1 through the absorption rod selector (S) 13. In the order loaded into the memory of the program control device 10, the actuator 2 of the absorption rod 1 is used to automatically take the absorption rod out of the core or put it into the position corresponding to the optimal shape of the energy release field in the core to achieve the set power generation value, and the position is loaded into the memory of the program control device 10 according to the calculation result.

[0062] In this case, the positive reactivity released by the taken-out absorber rod 1 is compensated by the negative reactivity introduced by the inserted absorber rod 1, thereby ensuring the required subcriticality.

[0063] If the reactor installation is provided with a reactor internal monitoring system for monitoring the coolant temperature field at the core outlet, the shape of the absorber rods 1 may be adjusted during the first movement during the annual planned preventive maintenance according to the actual coolant temperature at the core outlet to ensure temperature balance and thus achieve the set power generation value. In this case, the algorithm of the second startup stage "shape" is used.

[0064] After the second startup phase is completed, the third startup phase begins according to the "physical startup" command. In this case, the absorber rods 1 are powered by the selector (S) 13, and the actuators 2 of the absorber rods 1 automatically remove the absorber rods from the core in small intervals (for example, one percent of the complete stroke of the absorber rods) according to the sequence loaded into the memory of the program control device 10. Before the reactor reaches the critical state of the minimum controlled power level, the cycle of the reactor is limited by the set value of the comparison element 8. When the program control device 10 receives a signal from the comparison element (CB) 8 about reaching the set value of the minimum controlled control level, the removal of the absorber rods 1 is stopped and then maintained in automatic mode. The third startup phase ends here.

[0065] The maximum movement speed of the absorber rod 1 is controlled by hardware at a specific value, which ensures the maintenance of the quality required for the set power level and the quality of the transition process in the automatic power regulator mode when using the weakest absorber rod 1, which is almost completely loaded into or removed from the core, in compliance with the requirements of the normative documents.

[0066] When the reactor unit and turbine unit are ready for operation, the fourth startup phase begins in accordance with the "ready to power on" command. According to this command, the absorber rods 1 operating in the automatic power regulator mode are removed from the core in such quantity as to ensure that the actuator 2 automatically closes after the set cycle of the reactor, according to the imbalance signal between the actual cycle of the reactor and the set cycle provided by the comparison element 8. If the removal spacing of the absorber rods 1 has been set in the program control device 10 and the absorber rods cannot ensure the set cycle, the control automatically switches to the next absorber rod 1 according to the program loaded into the program control device 10. In this case, the power level begins to increase and, after several stages, maintains the set cycle until the power level reaches 3-5% of the rated power. When approaching the power level set in the program control device 10, the temperature / power negative feedback starts to operate to reduce the positive reactivity introduced. In this case, the absorber rods 1 in the automatic power regulator mode stabilize the power at the set value according to the signal sent from the comparison element 8 to the actuator 2.

[0067] Next, the fifth startup phase, which is also the last startup phase, is entered. After the end of this phase, the method for dynamically controlling the energy release field according to the present invention is started according to the "energy start" command. According to this command, when the reactor device and the turbine device are ready to operate, according to the imbalance signal between the set power and the actual power level provided by the comparison element 8, the absorption rod 1 selector (S) 13 is powered to the absorption rod, and the actuator 2 of the absorption rod 1 automatically removes the absorption rod from the core in a small interval (for example, one percent of the complete stroke of the absorption rod) according to the order loaded into the memory of the program control device 10 until the reactor reaches the power level set by the power setter 5 to compensate for the reactive power effect, and then automatically maintains the power level. In this case, the change rate of the reactor set power provided by the comparison element 8 should be consistent with the project set value, which can be achieved by using a corresponding power setter 5, which converts the sudden change of the set power into a time-extended change, corresponding to the power change rate set by the project. At this time, the energy start-up is completed and operation with the set constant power begins.

[0068] At this power level, the last absorber rod 1 operating under the automatic power regulator is removed so that the reactor is at the set power level, and the absorber rods are slowly removed from the core to compensate for the reactivity loss caused by burnup, accumulation of separation products and other processes of changes in nuclide composition, wherein such other processes are only related to reactor power generation (E).

[0069] For each absorber bar 1 operating under the automatic power regulator, before the automatic control switches to the next absorber bar 1, for each generation interval ΔE i The step of removing the absorber rod is determined by the new shape of the absorber rod 1 installed in the core, and the new installed shape is set in the memory of the program control device 10. The power generation interval is selected according to the calculation result, and the absorber rod is set in the memory of the program control device 10 according to the power generation interval. k Shape of the core loaded - h m (N, E), so that the relative shape of the absorber rod 1 is i and E i+1 There is no significant difference. i In terms of the relative shape of the absorber rod 1 and the power level N of the reactor, n Almost irrelevant. According to the program control device 10 sent about taking out the absorption rod 1 to the position h mThe signal is used to form a command for automatic control switching to the next absorption rod 1 in the program control device 10, and the command is sent to the program control device 10 by the position sensor (PD) 5 of the absorption rod 1, which is located on the actuator 2 of each absorption rod 1. After the last absorption rod 1 has finished operating in the automatic power regulator mode, if the set power level has not changed, the cycle is repeated for the next power generation interval.

[0070] If the set power level changes, power is supplied to the absorber rod 1 through the selector 13, and according to the imbalance signal between the new set power and the actual power level provided by the comparison element 8, the actuator 2 of the absorber rod 1 automatically removes the absorber rod from the core in a small interval (for example, one percent of the complete stroke of the absorber rod) according to the sequence loaded into the memory of the program control device 10, until the reactor reaches the new power level set by the power valuer 5 to compensate for the reactive power effect, and then automatically maintains the new power level. In this case, the power change rate of the reactor should meet the project set value, which can be achieved by adopting a corresponding power valuer.

[0071] In the proposed method, all absorber rods are included in an automatic control loop of the absorber rods, so that in the event of an extremely unlikely but in principle possible initiation event (multiple simultaneous failures of the control and protection systems, malicious behavior), a continuous and uncontrolled withdrawal of absorber rods from the core (absorber rod "self-removal") is possible, with the simultaneous release of a large amount of positive reactivity.

[0072] In a control and protection system with independent emergency protection rod groups, such "self-removal" of absorber rods may cause prompt neutron reactor stall, because the effectiveness of the independent emergency protection system is usually significantly lower than the total reactivity margin of all absorber rods.

[0073] This situation will not occur in the control and protection system according to the present invention, because when the set power level is exceeded, the reactor cycle drops below the set value or exceeds the coolant temperature set value, an emergency protection signal will be issued, which cannot be locked on the control console, or the control electromagnet windings of all absorber rod actuators will be de-energized through other emergency protection signals. Therefore, the absorber rods stop "self-removal", and when the control electromagnet windings are de-energized, all absorber rods perform the emergency protection function and drop to the lower limit switch in the core.

[0074] In order to improve the reliability of emergency protection activation, all circuits of all absorber rod actuators and emergency protection devices can be divided into two independent groups to ensure that the emergency protection function can still be performed when a failure occurs in one of the groups.

Claims

1. A method for controlling and protecting a fast neutron nuclear reactor by moving the absorption rods of an automatic power regulator, It is characterized in that include: - Calculate the position of the absorber rods to ensure that the energy release field has the best shape at each movement (generation); - according to the calculation results, loading a program with the movement sequence of the absorption rods (including taking out and loading in) into the memory of the program control device, so that the absorption rods are moved from the core to the position corresponding to the optimal shape of the energy release field to achieve the set power generation value; - turning on the automatic power regulator to change the position of the absorber rod according to a signal formed in a comparison element, the comparison element comparing the difference between the signal output by the power valuer and the power level sensor, and the difference between the set period of the neutron power multiplier and the actual period from the period measuring device in the start-up mode, wherein the signal is output from the neutron flux monitoring device to the power level sensor and the period measuring device; - making the reactor at a set energy power level corresponding to the loading shape of the absorption rods, automatically taking out the absorption rods or placing them in the core corresponding to the optimal energy release distribution according to the sequence loaded into the memory of the program control device to ensure the realization of the optimal shape of the energy release field, and loading into the program control device according to the calculation results, wherein the absorption rods are moved by the absorption rod actuator and the absorption rods are powered by the selector; - in the start-up mode of the reactor, the absorber rods are moved by the absorber rod actuator, power is supplied to the absorber rods through the selector, the absorber rods are automatically taken out from the core at small intervals in the order loaded into the memory of the program control device, the cycle of the reactor is limited by the set value of the comparison element before the reactor reaches the critical state of the minimum controlled power level, when the program control device receives a signal from the comparison element that the set value of the minimum controlled power level is reached, the absorber rods are stopped from being taken out, and then remain in the automatic mode; - removing the absorption rods operating at the minimum controlled power level in automatic power regulator mode from the core according to the imbalance signal between the actual cycle and the set cycle of the reactor provided by the comparison element, the number of which ensures that the absorption rod actuator is automatically closed after the set cycle of the reactor; and - based on the imbalance signal between the set power and the actual power level provided by the comparison element, the absorption rods are powered through the absorption rod selector, and the absorption rods are automatically taken out from the core at a certain interval in the order loaded into the memory of the program control device until the reactor reaches the power level set by the power setter to compensate for the reactive power effect, and then the power level is automatically maintained.

2. A control and protection system for a fast neutron nuclear reactor, include: An absorber rod that acts on reactivity, a neutron flux monitoring device, a control device, a plurality of absorber rod position sensors and indicators, a power valuer, a reactor cycle measuring device, a comparison element and an electric meter, wherein the absorber rod is provided with a plurality of actuators, each of which performs the functions of an automatic power regulator, a compensation rod and an emergency protection rod, the control device can form an early warning and emergency signal of the absorber rod position change, the comparison element can form a signal transmitted to the actuator, and the actuator can affect the movement of the absorber rod, characterized in that the control device includes a program control device for obtaining signals from a power level sensor, the electric meter and the absorber rod position sensor, and the function of automatically controlling power is transmitted from one absorber rod to another absorber rod through an absorber rod selector, so that the absorber rod moves during the movement, and the absorber rod system forms a certain loading shape according to the order loaded into the program control device and the absorber rod movement interval.

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