阅读说明：本技术 一种机泵模拟控制系统 (Pump analog control system ) 是由 李君� 时振堂 杜红勇 陶丽楠 刘维功 李琼 于 2018-06-15 设计创作，主要内容包括：本发明提供了一种机泵模拟控制系统,包括：直流电机负载转矩控制系统,类调门可调电阻控制系统和类管道可调线路控制系统,直流电机负载转矩控制系统为双闭环控制系统,用于模拟不同泵类负载特性；类调门可调电阻控制系统为单闭环控制系统,通过控制类调门可调电阻值大小,改变直流电机机械特性,使直流电机转速-转矩机械特性改变,模拟实际阀门能量损失；类管道可调线路控制系统为单闭环控制系统,通过控制类管道可调线路的相关参数大小,改变直流电机机械特性,使直流电机转速-转矩机械特性改变,模拟实际管道功率损失。本发明可以实现多种设备、多种工况能效模拟测试,解决企业中机泵实验难以开展的问题。(The invention provides a machine pump simulation control system, which comprises: the system comprises a direct current motor load torque control system, a quasi-gate adjustable resistance control system and a quasi-pipeline adjustable circuit control system, wherein the direct current motor load torque control system is a double closed-loop control system and is used for simulating different pump load characteristics; the analog regulating valve adjustable resistance control system is a single closed loop control system, and the mechanical characteristics of the direct current motor are changed by controlling the size of the adjustable resistance value of the analog regulating valve, so that the mechanical characteristics of the direct current motor rotating speed-torque are changed, and the energy loss of an actual valve is simulated; the pipeline-like adjustable line control system is a single closed-loop control system, and the mechanical characteristics of the direct current motor are changed by controlling the relevant parameters of the pipeline-like adjustable line, so that the rotation speed-torque mechanical characteristics of the direct current motor are changed, and the actual pipeline power loss is simulated. The invention can realize the energy efficiency simulation test of various devices and various working conditions and solve the problem that the pump experiment in enterprises is difficult to develop.)

1. A machine pump simulation control system based on a machine pump simulation system, characterized in that the machine pump simulation system comprises: the device comprises a direct current motor, a rectifier, a similar adjustable resistance and a similar pipeline adjustable circuit; the direct current motor is coaxially connected with a tested alternating current motor in a pump system of the tested machine to simulate the mechanical load of the alternating current motor; when the alternating current motor works in an electric state, the direct current motor works in a power generation state, and the electromagnetic power of the direct current motor is changed by adjusting the armature voltage of the direct current motor so as to simulate the torque change of the mechanical load of the alternating current motor; the tested alternating current motor is a prime motor of a pump system of the tested machine and is coaxially connected with the direct current motor; the direct current motor is connected with the direct current side of the rectifier, the armature voltage of the direct current motor is adjusted by adjusting the direct current side voltage of the rectifier, and the electromagnetic power of the direct current motor is further changed to simulate the torque change of the mechanical load of the alternating current motor; the rectifier is also used as the load of the direct current motor and feeds the electric energy of the direct current motor back to the power grid; the adjustable resistor of the analog regulating valve is used for simulating the characteristics of the regulating valve in the pump system of the tested machine; the pipeline-like adjustable circuit is used for simulating the pipeline characteristics in the pump system of the tested machine;

accordingly, the pump simulation control system comprises: DC motor load torque control system, class accent door adjustable resistance control system and class pipeline adjustable line control system, wherein:

the direct current motor load torque control system is a double closed loop control system, the armature voltage of the direct current motor is changed by controlling the direct current side voltage of the rectifier, and further the rotating speed-torque characteristic of the direct current motor is changed, so that a rotating speed-torque curve moves up and down, and intersects with a rotating speed-torque curve of a tested alternating current motor at different working points to simulate different pump load characteristics;

the analog regulating valve adjustable resistance control system is a single closed loop control system, and the mechanical characteristics of the direct current motor are changed by controlling the size of the analog regulating valve adjustable resistance value, so that the mechanical characteristics of the direct current motor rotating speed-torque are changed, and the energy loss of an actual valve is simulated;

the control system of the pipeline-like adjustable circuit is a single closed-loop control system, and the mechanical characteristics of the direct current motor are changed by controlling the size of relevant parameters of the pipeline-like adjustable circuit, so that the rotation speed-torque mechanical characteristics of the direct current motor are changed, and the actual pipeline power loss is simulated.

2. The machine-pump analog control system of claim 1, wherein the dc motor load torque control system is a torque-voltage double closed loop control system, the torque loop is an outer loop, the voltage loop is an inner loop, the outer loop realizes torque error-free control, and the inner loop realizes voltage fast tracking.

3. Pump analog control system according to claim 2, characterized in that the size T if to be generated_e ^*Mechanical torque of, set T_e ^*For setting value of torque ring, measuring parameter T by torque sensor of coupling system of AC motor-DC motor_eThe feedback value is obtained, the difference is made between the given value and the feedback value, and the difference is sent to a torque controller, and the output parameter of the torque controller is the given value of the armature voltage;

the given value of the voltage loop is the output of the torque loop, the feedback value of the voltage loop is the direct current voltage value of the rectifier measured by the voltmeter, and the inner loop controller realizes the tracking and the given.

4. The pump-on-demand simulation control system of claim 1, further comprising: the voltmeter, the ammeter, the rotating speed sensor and the torque sensor are respectively used for measuring voltage, current, rotating speed and torque parameters of corresponding devices.

5. The machine-pump analog control system of claim 1, wherein the dc motor torque characteristic is:

E_a＝U+(R_a+R₁+R₂)I_a

E_a＝C_eφn

T＝C_TφI_a

wherein E is_aIs armature electromotive force, U is armature voltage, R_aIs armature loop resistance, R₁For adjusting the adjustable resistance, R₂Is a pipe-like adjustable resistor, I_aIs armature current, C_eIs an electromotive constant, C_TPhi is the air gap flux, n is the DC motor speed, and T is the DC motor electromagnetic torque.

6. The pump simulation control system according to claim 1, wherein the size of the adjustable resistor of the analog gate is determined according to the consumption power of the regulating valve measured in advance, and the relation between the size of the adjustable resistor of the analog gate and the consumption power of the regulating valve is as follows:

P₁＝γQh_j

P₁＝I² _aR₁

wherein h is_jIs the local head loss, xi is the local resistance coefficient, v is the section average flow velocity, g is the gravity acceleration, P₁For fluid energy loss, gamma is the volume weight of the fluid being delivered, Q is the flow rate of the water pump, I_aIs armature current, R₁The adjustable resistor is a quasi-adjustable gate adjustable resistor.

7. The machine-pump simulation control system according to claim 1, wherein the pipeline-like adjustable circuit simulates the pipeline characteristics in the machine-pump system under test with a T-type circuit.

8. The pump simulation control system of claim 7, wherein the parameters of the adjustable line like a pipeline are determined according to pipeline parameters obtained by measurement in advance, and the relationship between the parameters of the adjustable line like a pipeline and the pipeline parameters is as follows:

L＝1/gA

R＝λ|Q|/(2gDA²)

C＝gA/a²

wherein L is equivalent inductance, R₂The method is similar to pipeline adjustable resistance, C is equivalent capacitance, g is gravity acceleration, A is pipeline section area, lambda is friction coefficient, Q is equivalent flow, D is pipeline diameter, A is pipeline section area, and a is water shock wave speed.

9. The machine-pump simulation control system according to claim 1, wherein the machine-pump energy efficiency obtained by the machine-pump simulation system simulation is as follows:

wherein T is the torque of the DC motor, omega is the rotating speed of the DC motor, U is the voltage of the AC motor to be measured, I is the current of the AC motor to be measured, and theta is the power factor.

10. The machine-pump simulation control system according to claim 1, wherein when the tested machine-pump system is a variable frequency speed control system, the machine-pump energy efficiency simulated by the machine-pump simulation system is as follows:

wherein T is the torque of the DC motor, omega is the rotating speed of the DC motor, U is the input voltage of the frequency converter, I is the fundamental wave current of the frequency converter, eta is_cIs the frequency converter efficiency.

Technical Field

The invention relates to the technical field of electric power simulation, in particular to a pump simulation control system.

Background

The motor is a driving device of a fan, a pump, a compressor and the like, is widely applied to the industrial and civil fields, and has energy consumption accounting for over 60 percent of the total social electricity consumption and over 70 percent of the total industrial electricity consumption. Energy conservation, emission reduction and green low-carbon development become the inherent requirements and development power of enterprises.

The pump regulating technology mainly comprises a variable frequency speed regulating technology, a hydraulic coupler technology, a permanent magnet speed regulator technology, a pole changing speed regulating technology, a phase control voltage regulating technology, a power factor compensation technology, a motor and dragging device, an operation condition matching technology, a motor system optimization and operation control technology and the like. The variable frequency speed regulation technology can realize the functions of soft start, process regulation, power factor correction and the like of the motor, and is used more; the pump matching technology can solve the problem of the incongruity between the rated power of the motor and the running power of the dragging equipment, and is a research hotspot.

Industrial enterprises, particularly large industrial enterprises such as petrochemical enterprises, steel enterprises, building materials enterprises and the like, have the advantages of strong process continuity, high automation degree, complex technology, high control precision of production process, high load importance level and complex load property, and can only perform steady-state test and not perform transient test. In the laboratory, can build small-size machine pump experimental system, test specific model machine pump, nevertheless can not realize the test experiment of multiple equipment.

Disclosure of Invention

Aiming at the defects in the prior art, the invention provides a machine pump simulation control system, which can realize the simulation of multiple working conditions and multiple types of machine pumps and solve the problem that machine pump experiments in enterprises cannot be developed.

In order to achieve the purpose, the invention provides the following technical scheme:

the invention provides a machine pump simulation control system based on a machine pump simulation system, which comprises: the device comprises a direct current motor, a rectifier, a similar adjustable resistance and a similar pipeline adjustable circuit; the direct current motor is coaxially connected with a tested alternating current motor in a pump system of the tested machine to simulate the mechanical load of the alternating current motor; when the alternating current motor works in an electric state, the direct current motor works in a power generation state, and the electromagnetic power of the direct current motor is changed by adjusting the armature voltage of the direct current motor so as to simulate the torque change of the mechanical load of the alternating current motor; the tested alternating current motor is a prime motor of a pump system of the tested machine and is coaxially connected with the direct current motor; the direct current motor is connected with the direct current side of the rectifier, the armature voltage of the direct current motor is adjusted by adjusting the direct current side voltage of the rectifier, and the electromagnetic power of the direct current motor is further changed to simulate the torque change of the mechanical load of the alternating current motor; the rectifier is also used as the load of the direct current motor and feeds the electric energy of the direct current motor back to the power grid; the adjustable resistor of the analog regulating valve is used for simulating the characteristics of the regulating valve in the pump system of the tested machine; the pipeline-like adjustable circuit is used for simulating the pipeline characteristics in the pump system of the tested machine;

accordingly, the pump simulation control system comprises: DC motor load torque control system, class accent door adjustable resistance control system and class pipeline adjustable line control system, wherein:

the direct current motor load torque control system is a double closed loop control system, the armature voltage of the direct current motor is changed by controlling the direct current side voltage of the rectifier, and further the rotating speed-torque characteristic of the direct current motor is changed, so that a rotating speed-torque curve moves up and down, and intersects with a rotating speed-torque curve of a tested alternating current motor at different working points to simulate different pump load characteristics;

the analog regulating valve adjustable resistance control system is a single closed loop control system, and the mechanical characteristics of the direct current motor are changed by controlling the size of the analog regulating valve adjustable resistance value, so that the mechanical characteristics of the direct current motor rotating speed-torque are changed, and the energy loss of an actual valve is simulated;

the control system of the pipeline-like adjustable circuit is a single closed-loop control system, and the mechanical characteristics of the direct current motor are changed by controlling the size of relevant parameters of the pipeline-like adjustable circuit, so that the rotation speed-torque mechanical characteristics of the direct current motor are changed, and the actual pipeline power loss is simulated.

Furthermore, the direct current motor load torque control system is a torque-voltage double closed-loop control system, the torque loop is an outer loop, the voltage loop is an inner loop, the outer loop realizes torque non-difference control, and the inner loop realizes voltage rapid tracking.

Further, if a size T is to be generated_e ^*Mechanical torque of, set T_e ^*For setting value of torque ring, measuring parameter T by torque sensor of coupling system of AC motor-DC motor_eThe feedback value is obtained, the difference is made between the given value and the feedback value, and the difference is sent to a torque controller, and the output parameter of the torque controller is the given value of the armature voltage;

the given value of the voltage loop is the output of the torque loop, the feedback value of the voltage loop is the direct current voltage value of the rectifier measured by the voltmeter, and the inner loop controller realizes the tracking and the given.

Further, the pump simulation system further includes: the voltmeter, the ammeter, the rotating speed sensor and the torque sensor are respectively used for measuring voltage, current, rotating speed and torque parameters of corresponding devices.

Further, the torque characteristics of the dc motor are:

E_a＝U+(R_a+R₁+R₂)I_a

E_a＝C_eφn

T＝C_TφI_a

wherein E is_aIs armature electromotive force, U is armature voltage, R_aIs armature loop resistance, R₁For adjusting the adjustable resistance, R₂Is a pipe-like adjustable resistor, I_aIs armature current, C_eIs an electromotive constant, C_TPhi is the air gap flux, n is the DC motor speed, and T is the DC motor electromagnetic torque.

Further, the size of the adjustable resistor of the analog regulating valve is determined according to the regulating valve power consumption obtained by measurement in advance, wherein the relationship between the size of the adjustable resistor of the analog regulating valve and the regulating valve power consumption is as follows:

P₁＝γQh_j

P₁＝I² _aR₁

wherein h is_jIs the local head loss, xi is the local resistance coefficient, v is the section average flow velocity, g is the gravity acceleration, P₁For fluid energy loss, gamma is the volume weight of the fluid being delivered, Q is the flow rate of the water pump, I_aIs armature current, R₁The adjustable resistor is a quasi-adjustable gate adjustable resistor.

Furthermore, the pipeline-like adjustable circuit adopts a T-shaped circuit to simulate the pipeline characteristics in the pump system of the tested machine.

Further, the parameters of the pipeline-like adjustable line are determined according to pipeline parameters obtained by measurement in advance, wherein the relationship between the parameters of the pipeline-like adjustable line and the pipeline parameters is as follows:

L＝1/gA

R＝λ|Q|/(2gDA²)

C＝gA/a²

wherein L is equivalent inductance, R₂The method is similar to pipeline adjustable resistance, C is equivalent capacitance, g is gravity acceleration, A is pipeline section area, lambda is friction coefficient, Q is equivalent flow, D is pipeline diameter, A is pipeline section area, and a is water shock wave speed.

Further, the mechanical pump energy efficiency obtained by the mechanical pump simulation system is as follows:

wherein T is the torque of the DC motor, omega is the rotating speed of the DC motor, U is the voltage of the AC motor to be measured, I is the current of the AC motor to be measured, and theta is the power factor.

Further, when the tested mechanical pump system is a variable frequency speed control system, the mechanical pump energy efficiency obtained by the mechanical pump simulation system is as follows:

wherein T is the torque of the DC motor, omega is the rotating speed of the DC motor, U is the input voltage of the frequency converter, I is the fundamental wave current of the frequency converter, eta is_cIs the frequency converter efficiency.

According to the above technical solution, the pump simulation control system provided by the present invention includes: the system comprises a direct current motor load torque control system, a quasi-gate adjustable resistance control system and a quasi-pipeline adjustable circuit control system, wherein the direct current motor load torque control system is a double closed loop control system, the armature voltage of the direct current motor is changed by controlling the direct current side voltage of a rectifier, and the rotating speed-torque characteristic of the direct current motor is further changed, so that a rotating speed-torque curve moves up and down and intersects with the rotating speed-torque curve of the tested alternating current motor at different working points to simulate different pump load characteristics; the analog regulating valve adjustable resistance control system is a single closed loop control system, and the mechanical characteristics of the direct current motor are changed by controlling the size of the analog regulating valve adjustable resistance value, so that the mechanical characteristics of the direct current motor rotating speed-torque are changed, and the energy loss of an actual valve is simulated; the control system of the pipeline-like adjustable circuit is a single closed-loop control system, and the mechanical characteristics of the direct current motor are changed by controlling the size of relevant parameters of the pipeline-like adjustable circuit, so that the rotation speed-torque mechanical characteristics of the direct current motor are changed, and the actual pipeline power loss is simulated. Therefore, the invention can realize the energy efficiency simulation test of various devices and various working conditions, and solves the problems that the test and error cost of an actual system is too high, and a laboratory system is difficult to simulate variable working condition pump loads, the characteristics of the regulating valve and the characteristics of a pipeline.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.

Fig. 1 shows a general configuration diagram of a pump simulation control system.

FIG. 2 shows a general block diagram of a pump simulation system;

FIG. 3 illustrates a functional schematic of the pump simulation system;

FIG. 4 illustrates a DC motor load torque control system operating schematic;

fig. 5 shows a pump characteristic simulation diagram of the pump simulation system.

Detailed Description

In order to make the objects, 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 with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The embodiment of the invention provides a pump simulation control system based on a pump simulation system, and the pump simulation system and the pump simulation control system can simulate the energy consumption condition of an actual pump system. The energy consumption of an actual pump system generally comprises three parts, namely pump load, regulating valve loss and pipeline loss, the test and error cost of the actual system is too high, and a laboratory system is difficult to simulate variable-working-condition pump load, regulating valve characteristics and pipeline characteristics. According to the embodiment of the invention, the DC motor is used for simulating the pump load, the adjustable resistance of the analog regulating valve is used for simulating the characteristics of the regulating valve, the analog pipeline adjustable circuit is used for simulating the characteristics of the pipeline, the DC motor load, the adjustable resistance of the analog regulating valve and the parameters of the analog pipeline adjustable circuit are regulated, and different working conditions can be simulated.

Referring to fig. 1 to 3, fig. 1 is a schematic diagram illustrating an overall structure of a pump simulation control system based on a pump simulation system according to an embodiment of the present invention; FIG. 2 shows a general block diagram of a pump simulation system; fig. 3 shows a working principle diagram of the pump simulation system.

Referring to fig. 2 and 3, the pump simulation system includes: the device comprises a direct current motor, a rectifier, a similar adjustable resistance and a similar pipeline adjustable circuit; the direct current motor is coaxially connected with a tested alternating current motor in a pump system of the tested machine to simulate the mechanical load of the alternating current motor; when the alternating current motor works in an electric state, the direct current motor works in a power generation state, and the electromagnetic power of the direct current motor is changed by adjusting the armature voltage of the direct current motor so as to simulate the torque change of the mechanical load of the alternating current motor; the tested alternating current motor is a prime motor of a pump system of the tested machine and is coaxially connected with the direct current motor; the direct current motor is connected with the direct current side of the rectifier, the armature voltage of the direct current motor is adjusted by adjusting the direct current side voltage of the rectifier, and the electromagnetic power of the direct current motor is further changed to simulate the torque change of the mechanical load of the alternating current motor; the rectifier is also used as the load of the direct current motor and feeds the electric energy of the direct current motor back to the power grid; the adjustable resistor of the analog regulating valve is used for simulating the characteristics of the regulating valve in the pump system of the tested machine; the pipeline-like adjustable circuit is used for simulating the pipeline characteristics in the pump system of the tested machine;

accordingly, referring to fig. 1, the pump analog control system includes: DC motor load torque control system, class accent door adjustable resistance control system and class pipeline adjustable line control system, wherein:

the direct current motor load torque control system is a double closed loop control system, the armature voltage of the direct current motor is changed by controlling the direct current side voltage of the rectifier, and further the rotating speed-torque characteristic of the direct current motor is changed, so that a rotating speed-torque curve moves up and down, and intersects with a rotating speed-torque curve of a tested alternating current motor at different working points to simulate different pump load characteristics;

the analog regulating valve adjustable resistance control system is a single closed loop control system, and the mechanical characteristics of the direct current motor are changed by controlling the size of the analog regulating valve adjustable resistance value, so that the mechanical characteristics of the direct current motor rotating speed-torque are changed, and the energy loss of an actual valve is simulated;

the control system of the pipeline-like adjustable circuit is a single closed-loop control system, and the mechanical characteristics of the direct current motor are changed by controlling the size of relevant parameters of the pipeline-like adjustable circuit, so that the rotation speed-torque mechanical characteristics of the direct current motor are changed, and the actual pipeline power loss is simulated.

As can be seen from the above description, the present embodiment provides a pump simulation control system, including: the system comprises a direct current motor load torque control system, a quasi-gate adjustable resistance control system and a quasi-pipeline adjustable circuit control system, wherein the direct current motor load torque control system is a double closed loop control system, the armature voltage of the direct current motor is changed by controlling the direct current side voltage of a rectifier, and the rotating speed-torque characteristic of the direct current motor is further changed, so that a rotating speed-torque curve moves up and down and intersects with the rotating speed-torque curve of the tested alternating current motor at different working points to simulate different pump load characteristics; the analog regulating valve adjustable resistance control system is a single closed loop control system, and the mechanical characteristics of the direct current motor are changed by controlling the size of the analog regulating valve adjustable resistance value, so that the mechanical characteristics of the direct current motor rotating speed-torque are changed, and the energy loss of an actual valve is simulated; the control system of the pipeline-like adjustable circuit is a single closed-loop control system, and the mechanical characteristics of the direct current motor are changed by controlling the size of relevant parameters of the pipeline-like adjustable circuit, so that the rotation speed-torque mechanical characteristics of the direct current motor are changed, and the actual pipeline power loss is simulated. Therefore, the embodiment can realize the simulation test of various equipment and various working conditions, and solves the problems that the test trial and error cost of an actual system is too high, and a laboratory system is difficult to simulate variable working condition pump loads, the characteristics of the regulating valve and the characteristics of a pipeline.

In a preferred embodiment, the dc motor load torque control system is a torque-voltage double closed loop control system, the torque loop is an outer loop, the voltage loop is an inner loop, the outer loop realizes torque error-free control, and the inner loop realizes voltage fast tracking.

In a preferred embodiment, if a size T is to be generated_e ^*Mechanical torque of, set T_e ^*A given value for the torque ring is specified,torque sensor measurement parameter T of AC motor-DC motor coupling system_eThe feedback value is obtained, the difference is made between the given value and the feedback value, and the difference is sent to a torque controller, and the output parameter of the torque controller is the given value of the armature voltage;

the given value of the voltage loop is the output of the torque loop, the feedback value of the voltage loop is the direct current voltage value of the rectifier measured by the voltmeter, and the inner loop controller realizes the tracking and the given.

According to the above description, the pump simulation control system provided in this embodiment can simulate the energy consumption condition of an actual pump system, and the structural schematic diagram of the system is shown in fig. 1, and first collects data of a system to be simulated, including pump load torque, valve pressure drop loss power, and pipeline resistance loss power, and then uploads the collected data to an upper computer for simulation.

The load torque control system of the direct current motor is a double closed-loop control system, the working principle of the system is shown in fig. 4, the armature voltage is the direct current side voltage of a rectifier, the rotating speed-torque mechanical characteristic of the motor can be changed by changing the armature voltage, a direct current generator or a controllable rectifier can be adopted for armature power supply, and the controllable rectifier is selected in the embodiment. The mechanical characteristic equation of the direct current motor is as follows:

wherein U is the armature voltage, R_aIs armature loop resistance, C_eIs an electromotive constant, C_TPhi is the air gap flux, n is the DC motor speed, and T is the DC motor electromagnetic torque.

The armature voltage is changed, the ideal no-load rotating speed of the mechanical characteristic is considered to be in direct proportion to the power voltage, and the mechanical characteristic curve is parallel to the inherent mechanical characteristic curve when the armature voltage value is different. The armature voltage of the direct current motor is changed to intersect with the mechanical characteristic curve of the alternating current motor at different working points, and load torque simulation is achieved.

The control system adopts torque-voltage double closed-loop control, the torque loop is an outer loop, and the voltage loop is an inner loop. For example, to generate a size ofT_e ^*Mechanical torque of, set T_e ^*For setting value of torque ring, measuring parameter T by torque sensor of coupling system of AC motor-DC motor_eThe feedback value is the difference between the set value and the feedback value, and the difference is fed into a torque controller, and the output parameter of the controller is the set value of the armature voltage. The torque controller can adopt various control methods, such as a classical PID method, a modern control theory zero pole configuration method, a neural network and other advanced control methods, and the PID method is selected in the embodiment because of the requirement of differential-free control.

Wherein, the parameters can be selected by an attenuation curve method, if the attenuation rate is set to be 0.75, the proportional band delta and the attenuation period T in the adjustment process of the system are recorded_sIf the PID proportion band is 0.8 delta, the integral parameter is 0.3T_sDifferential parameter of 0.1T_s。

The armature voltage control loop (inner loop) is given as torque loop output, and the feedback is a voltmeter to measure the direct-current voltage value of the rectifier. The inner loop controller mainly aims at tracking a given part, has high requirement on rapidity, does not require errors and therefore selects a proportional controller. The scale parameter selection method is as above, with the magnitude being δ.

The adjustable resistor of the analog adjusting door and the adjustable circuit of the analog pipeline are calculated according to an actual system and set in the system.

In a preferred embodiment, the pump simulation system further comprises: the voltmeter, the ammeter, the rotating speed sensor and the torque sensor are respectively used for measuring voltage, current, rotating speed and torque parameters of corresponding devices. For example, measuring the voltage and current of an alternating current motor, a direct current motor, an energy consumption resistor and a rectifier; the rotational speed and torque of the motor are measured.

In a preferred embodiment, the controller adjusts the dc side voltage of the rectifier to change the armature voltage of the dc motor, and further change the speed-torque characteristic of the dc motor, so that the speed-torque curve moves up and down and intersects with the speed-torque curve of the measured ac motor at different operating points, thereby simulating different pump load characteristics.

In a preferred embodiment, the dc motor torque characteristics are:

E_a＝U+(R_a+R₁+R₂)I_a (3)

E_a＝C_eφn (4)

T＝C_TφI_a (5)

wherein E is_aIs armature electromotive force, U is armature voltage, R_aIs armature loop resistance, R₁For adjusting the adjustable resistance, R₂Is a pipe-like adjustable resistor, I_aIs armature current, C_eIs an electromotive constant, C_TPhi is the air gap flux, n is the DC motor speed, and T is the DC motor electromagnetic torque.

The armature voltage is the rectifier DC side voltage, and the rotating speed-torque characteristic of the generator is changed by adjusting the rectifier DC voltage, namely changing the DC motor armature voltage, so that the rotating speed-torque curve moves up and down and intersects with the rotating speed-torque curve of the asynchronous motor to be tested at different working points, thereby simulating different pump load characteristics. Referring to FIG. 5, e.g. the asynchronous motor-DC generator has been operated at n₁At a rotational speed, changing the operating state to n₂The state and the steps are as follows, the armature voltage U of the direct current motor is reduced, and the counter electromotive force E is expressed by the formula (4)_aProportional to the rotation speed, temporarily keeping constant, increasing armature current by formula (3), increasing electromagnetic torque of the generator by formula (5), and decreasing the rotation speed to n in the transient process₂When the rotation speed of the asynchronous motor is reduced and the torque is increased, the asynchronous motor-direct current generator is balanced again. Stabilized DC machine E_aDecrease of I_aIncreasing, T increases.

In a preferred embodiment, the size of the trimming-gate adjustable resistor is determined according to the regulating valve power consumption measured in advance, wherein the relationship between the size of the trimming-gate adjustable resistor and the regulating valve power consumption is as follows:

P₁＝γQh_j (8)

P₁＝I² _aR₁ (9)

wherein h is_jIs the local head loss, xi is the local resistance coefficient, v is the section average flow velocity, g is the gravity acceleration, P₁For fluid energy loss, gamma is the volume weight of the fluid being delivered, Q is the flow rate of the water pump, I_aIs armature current, R₁The adjustable resistor is a quasi-adjustable gate adjustable resistor.

In a preferred embodiment, the pipeline-like adjustable circuit simulates the pipeline characteristics in the pump system of the tested machine by adopting a T-shaped circuit. The parameters of the pipeline-like adjustable line are determined according to pipeline parameters obtained by measurement in advance, wherein the relationship between the parameters of the pipeline-like adjustable line and the pipeline parameters is as follows:

L＝1/gA (10)

R＝λ|Q|/(2gDA²) (11)

C＝gA/a² (12)

wherein L is equivalent inductance, R₂The method is similar to pipeline adjustable resistance, C is equivalent capacitance, g is gravity acceleration, A is pipeline section area, lambda is friction coefficient, Q is equivalent flow, D is pipeline diameter, A is pipeline section area, and a is water shock wave speed.

In a preferred embodiment, the machine-pump energy efficiency simulated by the machine-pump simulation system is as follows:

wherein T is the torque of the DC motor, omega is the rotating speed of the DC motor, U is the voltage of the AC motor to be measured, I is the current of the AC motor to be measured, and theta is the power factor.

In a preferred embodiment, when the tested pump system is a variable frequency speed control system, the pump energy efficiency obtained by the simulation of the pump simulation system is as follows:

wherein T is the torque of the DC motor, omega is the rotating speed of the DC motor, U is the input voltage of the frequency converter, I is the fundamental wave current of the frequency converter, eta is_cIs the frequency converter efficiency.

As can be seen from the above description, the pump simulation control system provided in the embodiment of the present invention may also be referred to as a pump energy efficiency test control system, and may simulate the pump parameters, the regulating valve parameters, and the pipeline parameters of the enterprise under actual operating conditions. The direct current motor excitation and speed regulation system is decoupled, is an optimal speed regulation mode, and can accurately simulate pump loads. The direct current motor works in a generator state, and converts the energy of the alternating current motor into direct current electric energy which is transmitted to the rectifier. The adjustable resistance of the analog regulating valve simulates the loss of the regulating valve; pipeline-like adjustable lines simulate pipeline loss. The rectifier is a control power supply of the direct current generator and is also a load of the direct current generator, the armature voltage of the direct current motor is changed by adjusting the direct current side voltage of the rectifier, and further the torque of the direct current motor is changed, so that the requirement of simulating the pump torque is met.