CN117081033A - Parameter design method for fast switching device, storage medium and processor - Google Patents
Parameter design method for fast switching device, storage medium and processor Download PDFInfo
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Abstract
The embodiment of the application provides a parameter design method for a quick switching device, and belongs to the field of industrial electrical control. The parameter design method of the fast switching device comprises the following steps: collecting line connection modes and operation parameters of a power grid and load equipment of the industrial continuous production system; building a power grid-load integrated model according to the line connection mode and the operation parameters; carrying out anti-electric-shaking capability test on the power grid-load integrated model to obtain critical sag time of each load device under the condition that the load device meets the production process requirement; comparing the critical dip time of each load device, and taking the minimum value of the critical dip time as the total critical switching time of the industrial continuous production system; calculating capacity and current values required on the load side of the industrial continuous production system; and determining parameters of the fast switching device according to the capacity, the current value and the overall critical switching time.
Description
Technical Field
The application relates to the field of industrial production control, in particular to a parameter design method of a quick switching device, a storage medium and a processor.
Background
In the modern industrial production process, the requirement on the control precision of the production process is high, the production process is particularly sensitive to the interference of electricity, and serious accidents and losses can be caused by the production interruption caused by the interference of electricity. In particular, in the field of petrochemical production, multiple types of power electronic equipment are used on the source-network-load side, and as the devices are multiple, the process production process is complex, the working conditions are harsh, the connection among the process devices is very tight, the production process is very sensitive to voltage sag, the transient voltage stability problem is more complex, and higher requirements are also put forward on the transient voltage stability evaluation of the power system. In many abatement scheme designs, fast switching is used to handle the voltage sag of the bus, in combination with the PIT curve of the load, to reduce the likelihood of tripping of sensitive equipment during switching of the switch.
In the model selection work of the quick cutting device, if the duration of the process of completing the action of the quick cutting device is too long, the busbar is naturally out of voltage, the rotating speed of the motor is seriously reduced, the continuity of the production process is directly affected, but if the high performance of the quick cutting device is pursued, the great amount of unnecessary investment is increased. Therefore, the applicant finds out how to select a fast cutting device with proper parameters with reasonable investment, and ensuring the success rate of power switching and equipment safety is a problem which needs to be solved urgently in the current fast cutting device selection work.
Disclosure of Invention
The embodiment of the application aims to provide a parameter design method of a quick switching device, which is characterized in that a power grid-machine pump load integrated model is established, the relation between the technological parameters of each load device in the model, the voltage sag depth of the device parameters and the voltage sag time is researched, the capacity and the current value required by a load side are calculated, and the required quick switching device is selected according to the capacity and the current value.
In order to achieve the above object, an embodiment of the present application provides a method for designing parameters of a fast switching device for fast switching of electric power of an industrial continuous production system, including:
collecting line connection modes and operation parameters of a power grid and load equipment of the industrial continuous production system;
building a power grid-load integrated model according to the line connection mode and the operation parameters;
carrying out anti-electric-shaking capability test on the power grid-load integrated model to obtain critical sag time of each load device under the condition that the load device meets the production process requirement;
comparing the critical dip time of each load device, and taking the minimum value of the critical dip time as the total critical switching time of the industrial continuous production system;
calculating capacity and current values required on the load side of the industrial continuous production system;
and determining parameters of the fast switching device according to the capacity, the current value and the total critical switching time.
Furthermore, a simulation model meeting the parameters of the rapid switching device is added into the power grid-load integrated model, the new overall critical switching time of the industrial continuous production system is simulated and tested, and the validity of the parameters of the rapid switching device is judged.
Optionally, determining that the parameter of the fast switching device is valid when the new overall critical switching time of the industrial continuous production system is not greater than the expected overall critical switching time.
Preferably, the industrial continuous production system is a petrochemical production system or a metallurgical industrial continuous production system.
Further, the obtaining the critical sag time of each load device under the condition that the load device meets the production process requirement comprises: acquiring a critical rotation speed n1 of the load equipment meeting the production process requirement, and calculating a first process parameter immunization time T1 corresponding to the critical rotation speed n 1; acquiring a critical rotation speed n2 of the stable operation of the load equipment, wherein the second process parameter immune time T2 corresponding to the critical rotation speed n 2; the smaller of the first process parameter immunization time T1 and the second process parameter immunization time T2 is used as a critical sag time for the load device.
Preferably, if the critical sag time of the load device is PIT i The overall critical switching time PIT of the industrial continuous production system x The method comprises the following steps:
PIT x ＝min(PIT 1 ,PIT 2 ,...,PIT m ) In PIT k (k=1, 2, …, m) is the critical sag time of each individual load device.
Preferably, the rotation speed when the mechanical property and the load property of the motor of the load device simultaneously meet the following formula is the critical rotation speed n1 of the load device meeting the production process requirement:
T m ＝g(U 1 ,H)＝g(U 1 ,f(n))，
T L ＝k L n 2 ，
T m ＝T L and (2) and
wherein T is m Is a mechanical characteristic formula of the motor, wherein H=f (n) is used for representing a formula of the corresponding relation between parameters meeting the production process requirements and the rotating speed of the motor, and U 1 Is the voltage of the motor;
T L is the load characteristic formula of the motor, wherein k is L N is the rotational speed of the motor, which is the torque scaling factor.
Preferably, the rotation speed when the mechanical characteristic and the load characteristic of the motor of the load device simultaneously satisfy the following formula is the critical rotation speed n2 of the stable operation of the load device:
T L ＝k L n 2 ，
T m ＝T L and (2) and
wherein T is m Is a mechanical characteristic formula of the motor;
T L a load characteristic formula for the motor;
n is the rotational speed of the motor;
the other design parameters are that of the motor: k (k) L Is a torque proportional coefficient, p is a pole pair number, f 1 For the system frequency, r 1 And r 2 ' is stator resistance and leakage reactance, x 1 And x 2 ' rotor resistance and leakage reactance to stator side, U 1 The voltage of the motor and s are slip.
In another aspect, the present application provides a machine-readable storage medium having stored thereon instructions for causing a machine to perform the fast switching device parameter design method of any one of the above-described applications.
In yet another aspect, the present application provides a processor for executing a program, wherein the program is executed for executing the fast switching device parameter design method according to any one of the above-mentioned aspects of the present application.
Through the technical scheme, the anti-electric-shaking capacity evaluation and analysis platform is built, the power grid-machine pump load integrated model is built, the electric parameters and the technological parameters are combined, the selected electric parameters and technological parameters are different, and the corresponding critical sag time is also different. The relation between the sensitive load tolerance and the process protection value and the voltage sag depth and the voltage sag time is studied, the critical sag time of each parameter of the internal machine pump is compared longitudinally, the shortest critical sag time is used as the critical sag time of the whole system for stable operation, the capacity and the current value required by the load side are calculated according to nameplate parameters, and the required quick switching device is selected according to the switching time, the current and the capacity requirement. According to the technical scheme, the critical switching time of the stable operation of the whole system can be effectively determined, corresponding fast cutting is selected for treatment according to the power of sensitive equipment, the anti-interference electricity tolerance capability of important equipment of the device is improved, and the environment coordination and the safe yield increase are realized.
Additional features and advantages of embodiments of the application will be set forth in the detailed description which follows.
Drawings
The accompanying drawings are included to provide a further understanding of embodiments of the application and are incorporated in and constitute a part of this specification, illustrate embodiments of the application and together with the description serve to explain, without limitation, the embodiments of the application. In the drawings:
FIG. 1 is a flow chart of a fast-cutting parameter design method according to an embodiment of the application;
FIG. 2 is a flow chart of a method for designing fast cutting parameters based on process parameters PIT of a chemical process; and
fig. 3 is a schematic diagram of a design of an integrated power grid-machine pump load model based on a process parameter PIT of a chemical process.
Detailed Description
The following describes the detailed implementation of the embodiments of the present application with reference to the drawings. It should be understood that the detailed description and specific examples, while indicating and illustrating the application, are not intended to limit the application.
In order to better understand the technical scheme of the application, a theoretical basis of the immunization time of the process parameter in the application is introduced.
Modern industrial production processes are formed by connecting multiple devices in a certain mode, and the devices fail after being influenced by voltage sag, so that the process is interrupted. Following this logical sequence, the general flow for evaluating the voltage sag resistance characteristics of the process is to determine equipment failure first and then determine process interruption. For the judgment of equipment failure, the traditional evaluation is based on a Voltage Tolerance Curve VTC (Voltage-Tolerance Curve) of the equipment, and the affected state of the equipment is obtained by comparing the Voltage sag characteristic quantity with the Voltage Tolerance range of the equipment. The Shortwary team accounts for uncertainty in the sensitivity of the device and performs random fuzzy evaluation on the voltage sag failure event of the sensitive device. The harvard university Zhan Yi team analyzes the process flow and the device connection mode to evaluate the complex process from a single device. In practice, a single plant interruption does not immediately result in some process interruption, the essence of which is that physical parameters (such as temperature, speed, torque, pressure, etc.) reflecting the efficacy of the plant are outside the scope of the process requirements. CIGRE/CIRED joint working group C4.110 proposed the concept of process parameter immunization time PIT (Parameter Immunity Time) in 2010.
In some dips, no matter how long the dips last, the motor can stably operate, and the motor can return to the original stable operating point after the voltage is recovered. The safe voltage is defined as the voltage that must be re-accelerated to be successful after the voltage sag is eliminated. The minimum value of the safety voltage (the residual voltage value of the largest sag among the sags satisfying the aforementioned condition) is defined as the safety threshold voltage, that is, if the sag residual voltage is above the safety threshold voltage, the system is not destabilized for any long.
If the residual voltage value of the dip is below the safety threshold voltage, the motor may be operated for a while at the dip, but there is an instability problem at low speed. Defining the sag, the longest runnability time is a critical sag time. If the sag duration exceeds the critical sag time, the motor will be unstable even if the voltage is restored. The existing treatment method is to distinguish electrical parameters and technological parameters, and electrical treatment means are adopted for an electrical sensitive process; for the parameter induction type process, the electrical and physical treatment means are comprehensively utilized. The scheme combines the electrical parameters and the process parameters, and the selected electrical parameters and process parameters are different, and the corresponding critical sag time is also different. And (3) longitudinally comparing critical sag time of each parameter of the pump of the internal machine of the model, and taking the shortest critical sag time as the critical sag time of stable operation of the whole system.
The fast cutting device is widely applied to substations, power plants, industrial and mining enterprises and the like, is a power supply fast switching device for ensuring the power utilization safety of the station (plant), optimizes the fast cutting device, and is beneficial to ensuring the fast and reliable action of the fast cutting device and the safe and stable operation of the power utilization of the station (plant). The starting mode of the quick switching device comprises a normal switching mode, an accident switching mode and an abnormal switching mode. According to different starting modes, the device has parallel switching, serial switching and simultaneous switching.
The parallel switching is started manually, when the pressure difference, the frequency difference and the phase difference of the two sides of the working power circuit breaker and the standby power circuit breaker are respectively smaller than the normal parallel switching pressure difference, the frequency difference and the phase difference, the quick switching device is used for combining the standby (working) circuit breaker firstly, and then automatically tripping the working (standby circuit breaker) after a certain time delay, if the standby (working) power circuit breaker which is just closed is tripped in the time delay, the quick switching device is not automatically tripped (standby) any more, so that the power loss of the factory power is avoided. If the parallel switching condition is not satisfied after the starting, the device will lock and send out signals and enter a state waiting for manual reset. The parallel switching is divided into parallel automatic and parallel semiautomatic, and the main difference is that the standby (working) circuit breaker is closed, and if the standby circuit breaker is automatically tripped, the parallel automatic switching is realized; if the operating personnel manually operate the tripping (standby) circuit breaker, the parallel semi-automatic switching is performed. The parallel switching does not cause interruption of station service power in the switching process, but the power supplies at the two sides are in short-time parallel operation.
The serial switching is started manually, a tripping operation (standby) breaker command is issued first, and when the tripping operation (standby) breaker is confirmed and the switching mode condition is satisfied, a standby (operation) power supply is closed. The normal series switching can cause short-time interruption of station service power in the switching process, and is suitable for 2 switching power supplies with very large inherent phase difference of a difference frequency system or a same frequency system, and the mode comprises 4 implementation modes of fast switching, synchronous capturing switching, residual voltage switching and long-time delay switching.
Meanwhile, the switching is started manually, the tripping operation and the switching-on standby command are sent out simultaneously, and because the inherent switching-on time is generally longer than the switching-off time, a manually set delay exists before the switching-on command is sent out, so that the switching-off is finished before the switching-on. The simultaneous switching is suitable for power supply switching between the same-frequency and difference-frequency systems, and the mode comprises 4 implementation modes of fast switching, synchronous capturing switching, residual voltage switching and long-time delay switching. And when the quick cutting is unsuccessful, the synchronous capturing, residual voltage and long-delay switching mode can be automatically switched.
The use effect of the traditional quick cutting device is quite unsatisfactory. The reason is that most of the load in the factory comes from the motor, and the duration of the process of completing the action of the quick cutting device from the power failure to the no-voltage process is as long as 1-2 s or more due to the existence of the feedback voltage of the motor, and at the moment, the motor is cut off by batch power failure. Even if the high voltage with long delay time is important that the motor is not cut off, the rotating speed is seriously reduced because the bus is not pressed, the continuity of the production process is directly affected, and the product quality is adversely affected. And at the moment, the power supply is restored to cause the self-starting of a larger motor, and the large current impacts the power supply network. For 400V systems, the low voltage will cause the contactor to trip and the inverter stops operating. At this time, the quick cutting device does not actually play a role in guaranteeing the power supply continuity.
After the application is designed for the 35kV side fast switching application of the chemical device, the impact on a motor caused by overlarge differential pressure between the bus voltage (residual voltage) and the standby power supply voltage can be avoided, and the power-off time is shortened; the switching of quick switching, synchronous discrimination or residual voltage discrimination can be adopted, so that the switching-on time of the two sections of mutual switching quick circuit breakers is less than 200ms, and the power failure and tripping condition of the motor in field operation is reduced. When the bus is faulty, the device can be immediately locked and the fault is not expanded, so that the success rate of switching the station service electricity is improved, the safety of equipment is ensured, and meanwhile, more reliable and powerful power supply guarantee is provided for each production device, so that each production device operates more safely and stably
According to the application, the process parameters PIT of the chemical process are combined for the first time, the anti-shaking capacity evaluation analysis platform of the chemical production process is built, the power grid-machine pump load integrated model is built, the relation between the sensitive load tolerance and the process protection value and the voltage sag depth and the voltage sag time is studied, the critical sag time of all machine pumps in the model is compared longitudinally, the shortest critical sag time is used as the critical switching time of the stable operation of the whole system, the capacity and the current value required by the load side are calculated according to the parameters, and the required quick switching device is selected.
The flow of the fast-cutting parameter design method according to an embodiment of the application is shown in fig. 1, and the selection thereof comprises the following steps:
(1) Collecting various parameters of a circuit and a pump of the system;
(2) Building a power grid-machine pump load integrated model;
(3) Testing the anti-electric-shaking capability of the model, and counting critical dip time of all machine pumps under different voltage drop depths;
(4) The critical dip time of all machine pumps in the model is used as the critical switching time of the stable operation of the whole system by longitudinal comparison;
(5) And calculating the capacity and the current value required by the load side according to the nameplate parameters, and selecting the required quick switching device according to the switching time, the current and the capacity requirement.
After the steps are finished, further performing simulation test to verify the anti-interference effectiveness of the type-selecting device, wherein the specific implementation steps are that the steps (2) - (5) are repeatedly executed, the type-selecting switching device is added into the built model, and then the verification is performed step by step until the simulation model added into the quick-cutting device is ensured to meet the anti-interference strategy requirement effectiveness.
In order to enable those skilled in the art to understand the method for determining critical sag time according to the present application, the following will further describe how to calculate the critical sag time of the electric traction system, and other devices may be implemented according to the category, which is not described in detail herein.
The rotation equation of the electric traction system is:
in the electromagnetic torque T m And a load torque T L The unit of (2) is N.m; the unit of the moment of inertia J is kg.m 2 The method comprises the steps of carrying out a first treatment on the surface of the The angular velocity Ω is in rad/s. In engineering calculations, the angular velocity is generally replaced by a rotational speed n (in r/min),
with flywheel moment GD 2 Instead of moment of inertia J, therefore, the equation of rotation of the single-axis electric traction system can be rewritten as
T Δ ＝T m -T L (4)
From the above, the rotational speed of the electric traction system is changed by the dynamic torque T Δ Determining T Δ =0, the motor is rotating at constant speed or stationary, the electric traction system is stationary; if T Δ Not equal to 0, the motor speed will change, called a dynamic or transitional state. When T is Δ When the system is more than 0, the system is in an acceleration state; conversely, the system is in a deceleration state.
The electric dragging system which is operated at a certain rotating speed originally is subject to certain disturbance from the outside, such as sudden change of load, fluctuation of network voltage and the like, so that the rotating speed of the system is changed and is away from the original balance state, and if the system can reach a new balance state under the condition, or can automatically recover to the original rotating speed to continue to operate after the external disturbance disappears, the system is said to be stable; if the rotational speed of the system increases either unrestrained or drops straight down to zero after the external disturbance has disappeared, the system is said to be unstable.
Whether an electric traction system can stably operate or not is determined by the coordination of mechanical characteristics of a motor and load torque characteristics. To achieve stable operation, motor mechanical characteristics are also required to be matched to load characteristics. The requirement for stable operation of the chemical plant is that the mechanical characteristics of the motor and the torque characteristics of the load must have an intersection point, i.e. T m ＝T L The method comprises the steps of carrying out a first treatment on the surface of the The sufficiency condition is that at the intersection point, the following is satisfied:
simplifying the equivalent circuit to obtain the mechanical characteristic formula of the three-phase asynchronous motor,
wherein p is the pole pair number; f (f) 1 Is the system frequency; r is (r) 1 、r 2 ' is stator resistance and leakage reactance; x is x 1 、x 2 ' is rotor resistance and leakage reactance reduced to the stator side; u (U) 1 Is a voltage; s is slip.
The load can be divided into a constant torque load, a fan pump load and a constant power load according to the mechanical characteristics of the load, the common fluid machinery such as a blower, a water pump and the like in a chemical device system belongs to the fan pump load, the torque is in direct proportion to the square of the rotating speed, and the mechanical characteristics are as follows:
T L ＝k L n 2 (7)
wherein k is L Is a torque scaling factor.
According to the sufficient and necessary conditions of the stable operation of the chemical device, the combined type (6) and the formula (7) obtain the solution of the equation, which is:
n＝n 1 ,n＝n 2 (8)
wherein n is 1 、n 2 Is the two intersections of the mechanical characteristic curve and the load mechanical characteristic curve of the three-phase asynchronous motor in the chemical systemThe points correspond to rotational speed values.
Bringing equation (8) into equation (5), and obtaining the critical rotation speed n of steady-state operation of single sensitive equipment under a certain voltage sag depth according to the judging condition 1 。
Will n 1 Carrying into (9) to obtain the process immunization time t of a single sensitive device under a certain voltage sag depth c 。
Calculating the immune time of a single sensitive device process under a certain voltage sag depth according to the rotating speed, and judging whether the motor is locked or not;
taking the process immunization time evaluation of a chemical device with process parameters as an example, firstly obtaining a relation between the flow H and the rotating speed n:
H＝f(n) (10)
taking equation (10) into equation (5), a relationship between flow rate and electromagnetic torque is obtained:
T m ＝g(U 1 ,H)＝g(U 1 ,f(n)) (11)
according to the sufficient and necessary conditions of the stable operation of the chemical device, the combined type (11) and the formula (7) obtain the solution of the equation, which is:
n＝n 1 ,n＝n 2 (12)
bringing formula (12) into formula (8),
and then according to the process judging condition, namely, when the chemical device operates, the process parameter has a certain threshold value: h min ＜H＜H Rated for Obtaining the critical rotation speed n of steady-state operation of single sensitive equipment under a certain voltage sag depth 1 。
Will n 1 Carrying into (9) to obtain the process immunization time t of a single sensitive device under a certain voltage sag depth c 。
From the logical relationship of the devices and the respective PIT curves, the comprehensive PIT of the whole chemical plant can be obtained by the following formula (13):
PIT x ＝min(PIT 1 ,PIT 2 ,...,PIT m ) (13)
in the formula, PIT x The comprehensive PIT of the whole chemical device; PIT (PIT) k (k=1, 2, …, m) is the process immunization time for each individual device.
According to the embodiment, the immunity time PIT combined with the industrial process parameters is realized by combining the electrical parameters and the process parameters, the parameter setting and the type selection can be carried out on the rapid switching device, the critical switching time of the stable operation of the whole system can be effectively determined, the corresponding rapid switching is selected according to the power of sensitive equipment to carry out treatment, the anti-interference electricity tolerance capability of important equipment of the device is improved, and the environment coordination and the safety yield increase are realized.
Another embodiment of the present application is a fast-cutting parameter design method based on the process parameter PIT of the chemical process, please refer to fig. 2. In this embodiment, the method for designing the fast cutting parameters based on the process parameters PIT of the chemical process includes the following steps:
(1) Collecting various parameters of a circuit and a pump in the system;
(2) Building a power grid-machine pump load integrated model;
(3) Carrying out voltage sag tolerance test on the integrated model;
(4) Counting critical dip time of all machine pumps under different voltage drop depths;
(5) Determining parameters of quick cutting equipment required by a system;
(6) Setting up a simulation model added with the quick cutting device;
(7) Determining whether the voltage drop time is shortened compared with that before the treatment, if so, indicating that the treatment scheme is effective,
if not, the treatment effect is not ideal.
The design schematic diagram of the power grid-machine pump load integrated model corresponding to the embodiment is shown in fig. 3, and includes corresponding voltage class buses and outgoing lines thereof, a fast switching device, a motor and pump loads carried by the motor. After the parameter selection of the quick switching device is completed, a corresponding voltage class bus and an outlet thereof, the quick switching device, the motor and pump loads carried by the motor are built in the model, and the pump loads are classified according to the types of centrifugal pumps, fans and the like, so that the effectiveness of the type selection result of the quick switching device can be verified for multiple times.
In this embodiment, the stage of building the sensitive device voltage sag tolerance analysis test and evaluation platform completes the following tasks: and building a model according to an actual power grid topological structure, and setting parameters of the transformer and the circuit according to actual data. The model comprises the following components: 110kV bus and outgoing line thereof, 35kV bus and outgoing line thereof, and all outgoing lines and load models of 6kV bus. Important loads include a pellet water pump MP-30801, a propylene feed pump MP-30301, a jacket water pump MP-30205, a refrigerator MPK-30401, a circulating pump MP-30201, a circulating compressor set MC-30401, a powder conveying nitrogen compressor MC-30801 and a circulating gas compressor MPK-30301, a blower MC-30902, a drying blower MC-30502, a pellet conveying blower MC-30804 and a pellet conveying blower MC-30905.
After the sensitive equipment voltage sag tolerance analysis test and evaluation platform is built, the following steps are carried out: the anti-interference electricity tolerance capability analysis test and evaluation are carried out by combining the process protection value of the important equipment, and the anti-interference electricity strategy research is carried out from alternating current detection, direct current side and sensitive load, including but not limited to series connection type, parallel connection type, coil type, plant type and other strategies, the anti-interference electricity strategy research of the important equipment of the device is carried out, and the type selection is carried out on the quick cutting device applied to the anti-interference electricity strategy of the important equipment.
The rated voltage is 6kV according to the installation position of the spare power automatic switching, and the rated current is calculated through the maximum value of the load capacity at the left side and the right side. Table 1 shows the technical indexes of the fast-switching switch required in this example.
Table 1 fast change-over switch technical index
In the case of current selection, the residual width of 1.2 times in the field calculation was 1.5 times in the load capacity due to the 400V class load loss, and table 2 shows the rated power of the motor for each load.
Table 2 rated power of motor for each load
According to the calculation, the total load of the 6kV I section is about 4.8MW, and the total load of the 6kV II section is about 4.7MW. Setting the total load of the section I as a reference, the calculated total capacity is obtained as follows:
4.8×1.5＝7.2MW
the calculated current values are as follows:
7.2÷6＝1.2kA
thus, a device with a rated current of 1250A and a rated voltage of 6kV was selected quickly.
And finally, further analyzing, testing and evaluating the effectiveness of the quick cutting device in improving the anti-electric-shaking capability of the equipment.
This embodiment achieves the following beneficial effects:
(1) The electric parameters and the technological parameters are combined for the first time at home and abroad, the immune time PIT combined with the chemical process parameters is realized, a power grid-machine pump load integrated model is built, and the relation between the sensitive load tolerance and the technological protection value and the voltage sag depth and the voltage sag time is researched.
(2) And (3) longitudinally comparing critical dip time of all the machine pumps in the model, taking the time with the shortest critical dip time as the fast switching time of the stable operation of the whole system, calculating the capacity and current value required by the load side according to nameplate parameters, and selecting the required fast switching device according to the switching time, current and capacity requirements.
The embodiment of the application provides a storage medium, on which a program is stored, which when executed by a processor, implements the fast switching device parameter design method.
The embodiment of the application provides a processor which is used for running a program, wherein the parameter design method of a quick switching device is executed when the program runs.
The embodiment of the application provides equipment, which comprises a processor, a memory and a program stored in the memory and capable of running on the processor, wherein the processor realizes the following steps when executing the program:
collecting line connection modes and operation parameters of a power grid and load equipment of the industrial continuous production system;
building a power grid-load integrated model according to the line connection mode and the operation parameters;
carrying out anti-electric-shaking capability test on the power grid-load integrated model to obtain critical sag time of each load device under the condition that the load device meets the production process requirement;
comparing the critical dip time of each load device, and taking the minimum value of the critical dip time as the total critical switching time of the industrial continuous production system;
calculating capacity and current values required on the load side of the industrial continuous production system;
determining parameters of the fast switching device according to the capacity, the current value and the overall critical switching time;
and adding a simulation model meeting the parameters of the rapid switching device into the power grid-load integrated model, simulating and testing the new overall critical switching time of the industrial continuous production system, and judging the validity of the parameters of the rapid switching device.
Wherein, when the new overall critical switching time of the industrial continuous production system is not more than the expected overall critical switching time, the parameters of the rapid switching device are determined to be effective;
the industrial continuous production system may be a petrochemical production system;
the obtaining the critical dip time of each load device under the condition that the load device meets the production process requirement comprises the following steps: acquiring a critical rotation speed n1 of the load equipment meeting the production process requirement, and calculating a first process parameter immunization time T1 corresponding to the critical rotation speed n 1; acquiring a critical rotation speed n2 of the stable operation of the load equipment, wherein the second process parameter immune time T2 corresponding to the critical rotation speed n 2; the smaller of the first process parameter immunization time T1 and the second process parameter immunization time T2 is taken as a critical sag time of the load device;
if the critical sag time of the single load device is PIT i The overall critical switching time PIT of the industrial continuous production system x The method comprises the following steps: PIT (PIT) x ＝min(PIT 1 ,PIT 2 ,...,PIT m ) In PIT k (k=1, 2, …, m) is the critical sag time of each individual load device.
The rotation speed when the mechanical property and the load property of the motor of the load equipment simultaneously meet the following formula is the critical rotation speed n1 of the load equipment meeting the production process requirement:
T m ＝g(U 1 ,H)＝g(U 1 ,f(n))，
T L ＝k L n 2 ，
T m ＝T L and (2) and
wherein T is M Is a mechanical characteristic formula of the motor, wherein H=f (n) is used for representing a formula of the corresponding relation between parameters meeting the production process requirements and the rotating speed of the motor, and U 1 In the form of a voltage, the voltage is,
T L for the load characteristic formula of the motor,
n is the rotational speed of the motor.
The rotation speed when the mechanical characteristic and the load characteristic of the motor of the load device simultaneously meet the following formula is the critical rotation speed n2 of the stable operation of the load device:
T L ＝k L n 2 ，
T m ＝T L and (2) and
wherein T is M T is the mechanical characteristic formula of the motor L The load characteristic formula of the motor is that n is the rotating speed of the motor, and the other parameters are the design parameters of the motor: k (k) L Is the torque proportionality coefficient, p is the pole pair number, f1 is the system frequency, r1 and r2 'are the stator resistance and leakage reactance, x1 and x2' are the rotor resistance and leakage reactance calculated to the stator side, U 1 The voltage, s, is slip.
The device herein may be a server, PC, PAD, cell phone, etc.
The beneficial effects of the storage medium embodiment of the present application are the same as those of the method embodiment, and are not described here again.
The application also provides a computer program product adapted to perform, when executed on a data processing device, a program initialized with the method steps of:
collecting line connection modes and operation parameters of a power grid and load equipment of the industrial continuous production system;
building a power grid-load integrated model according to the line connection mode and the operation parameters;
carrying out anti-electric-shaking capability test on the power grid-load integrated model to obtain critical sag time of each load device under the condition that the load device meets the production process requirement;
comparing the critical dip time of each load device, and taking the minimum value of the critical dip time as the total critical switching time of the industrial continuous production system;
calculating capacity and current values required on the load side of the industrial continuous production system;
determining parameters of the fast switching device according to the capacity, the current value and the overall critical switching time;
and adding a simulation model meeting the parameters of the rapid switching device into the power grid-load integrated model, simulating and testing the new overall critical switching time of the industrial continuous production system, and judging the validity of the parameters of the rapid switching device.
The beneficial effects of the computer program product embodiment of the present application are the same as those of the method embodiment, and are not described here again.
It will be appreciated by those skilled in the art that embodiments of the present application may be provided as a method, system, or computer program product. Accordingly, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present application may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein.
The present application is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems) and computer program products according to embodiments of the application. It will be understood that each flow and/or block of the flowchart illustrations and/or block diagrams, and combinations of flows and/or blocks in the flowchart illustrations and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.
These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.
These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.
In one typical configuration, a computing device includes one or more processors (CPUs), input/output interfaces, network interfaces, and memory.
The memory may include volatile memory in a computer-readable medium, random Access Memory (RAM) and/or nonvolatile memory, etc., such as Read Only Memory (ROM) or flash RAM. Memory is an example of a computer-readable medium.
Computer readable media, including both non-transitory and non-transitory, removable and non-removable media, may implement information storage by any method or technology. The information may be computer readable instructions, data structures, modules of a program, or other data. Examples of storage media for a computer include, but are not limited to, phase change memory (PRAM), static Random Access Memory (SRAM), dynamic Random Access Memory (DRAM), other types of Random Access Memory (RAM), read Only Memory (ROM), electrically Erasable Programmable Read Only Memory (EEPROM), flash memory or other memory technology, compact disc read only memory (CD-ROM), digital Versatile Discs (DVD) or other optical storage, magnetic cassettes, magnetic tape magnetic disk storage or other magnetic storage devices, or any other non-transmission medium, which can be used to store information that can be accessed by a computing device. Computer-readable media, as defined herein, does not include transitory computer-readable media (transmission media), such as modulated data signals and carrier waves.
It should also be noted that the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one … …" does not exclude the presence of other like elements in a process, method, article or apparatus that comprises an element.
The foregoing is merely exemplary of the present application and is not intended to limit the present application. Various modifications and variations of the present application will be apparent to those skilled in the art. Any modification, equivalent replacement, improvement, etc. which come within the spirit and principles of the application are to be included in the scope of the claims of the present application.
Claims (10)
1. A method for designing parameters of a fast switching device for fast switching of electric power of an industrial continuous production system, comprising:
collecting line connection modes and operation parameters of a power grid and load equipment of the industrial continuous production system;
building a power grid-load integrated model according to the line connection mode and the operation parameters;
carrying out anti-electric-shaking capability test on the power grid-load integrated model to obtain critical sag time of each load device under the condition that the load device meets the production process requirement;
comparing the critical dip time of each load device, and taking the minimum value of the critical dip time as the total critical switching time of the industrial continuous production system;
calculating capacity and current values required on the load side of the industrial continuous production system; and determining parameters of the fast switching device according to the capacity, the current value and the overall critical switching time.
2. The rapid switching device parameter design method of claim 1, further comprising:
and adding a simulation model meeting the parameters of the rapid switching device into the power grid-load integrated model, simulating and testing the new overall critical switching time of the industrial continuous production system, and judging the validity of the parameters of the rapid switching device.
3. The method for designing parameters of a fast switching device according to claim 2, wherein,
and determining that the parameters of the rapid switching device are valid in the case that the new overall critical switching time of the industrial continuous production system is not greater than the expected overall critical switching time.
4. The method for designing parameters of a fast switching device according to claim 1, wherein,
the industrial continuous production system is a petrochemical continuous production system or a metallurgical industrial continuous production system.
5. The method for designing parameters of a fast switching device according to claim 4, wherein said obtaining a critical sag time for each of said load devices to meet a production process requirement comprises:
acquiring a critical rotation speed n1 of the load equipment meeting the production process requirement, and calculating a first process parameter immunization time T1 corresponding to the critical rotation speed n 1;
acquiring a critical rotation speed n2 of the stable operation of the load equipment, wherein the second process parameter immune time T2 corresponding to the critical rotation speed n 2; and
the smaller of the first process parameter immunization time T1 and the second process parameter immunization time T2 is used as a critical sag time for the load device.
6. The method of claim 5, wherein if the critical sag time of each load device is PIT i The overall critical switching time PIT of the industrial continuous production system x The method comprises the following steps:
PIT x ＝min(PIT 1 ,PIT 2 ,...,PIT m )，
in the formula, PIT k (k=1, 2, …, m) is the critical sag of each individual load deviceAnd (3) the room(s).
7. The method according to claim 5, wherein the rotation speed when the mechanical characteristics and the load characteristics of the motor of the load device satisfy the following formulas is the critical rotation speed n1 of the load device satisfying the production process requirement:
T m ＝g(U 1 ,H)＝g(U 1 ,f(n))，
T L ＝k L n 2 ，
T m ＝T L and (2) and
wherein T is m Is a mechanical characteristic formula of the motor, wherein H=f (n) is used for representing a formula of the corresponding relation between parameters meeting the production process requirements and the rotating speed of the motor, and U 1 Is the voltage of the motor;
T L is the load characteristic formula of the motor, wherein k is L N is the rotational speed of the motor, which is the torque scaling factor.
8. The method according to claim 5, wherein the rotation speed when the mechanical characteristics and the load characteristics of the motor of the load device satisfy the following formulas at the same time is a critical rotation speed n2 at which the load device stably operates:
T L ＝k L n 2 ，
T m ＝T L and (2) and
wherein T is m Is a mechanical characteristic formula of the motor;
T L a load characteristic formula for the motor;
n is the rotational speed of the motor;
the other design parameters are that of the motor: k (k) L Is a torque proportional coefficient, p is a pole pair number, f 1 For the system frequency, r 1 And r 2 ' is stator resistance and leakage reactance, x 1 And x 2 ' rotor resistance and leakage reactance to stator side, U 1 The voltage of the motor and s are slip.
9. A machine-readable storage medium having instructions stored thereon for causing a machine to perform the fast switching device parameter design method of any one of claims 1-8.
10. A processor configured to execute a program, wherein the program is configured to, when executed, perform: a fast switching device parameter design method according to any one of claims 1-8.
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