RU2044214C1 - Superheated steam pressure regulator for multi-fuel generator - Google Patents

Abstract

FIELD: heat power engineering. SUBSTANCE: pressure regulator has calculator 12 and multiplier 13. Output of multiplying unit 7 with controllable fuel supply is connected with the input of calculator 12. The output of calculator 12 is connected with the inlet of adder 13. The first output of fuel supply regulator 10 is connected to the second input of multiplier 13. The second output of fuel supply controller 10 is connected with the second input of calculator 12. Output of multiplier 13 is connected with the inlet of actuator 11. EFFECT: improved design. 1 dwg

Description

 The invention relates to heat engineering and is used when co-burning several types of fuel, the flow rate of one of which can be controlled, and the flow rates of the rest can change quite often in an arbitrary way.

 Known controller of the combustion process, in which the output signal of the main steam pressure regulator is fed to the input of the heat load controller, the output signal of which is used to control the fuel supply. An executive body of stepless regulation of fuel supply is an electric motor of dust collectors. The method of controlling the speed of the dust collector motor is based on a change in the excitation current of the DC motor. The disadvantage of this device is that this scheme is not applicable if the supply of certain types of fuel is not regulated and can be changed arbitrarily.

 Known pressure regulator of superheated steam in a multi-fuel steam generator, which calculates the calorific value of each type of fuel. The total calorific value is compared with the reference signal of the integrated output signal of the heat load controller. The disadvantage of this device is that the fuel supply regulator does not take into account information about the current value of the calorific value of fuel with an adjustable supply, which does not allow adapting the control action with disturbances with maximum speed and minimizing the error of the stabilized parameter.

 The purpose of the invention is to improve the accuracy of the control system by reducing the error of the stabilized parameter.

 The essence of the invention lies in the fact that in the device containing sensors and controllers associated with the unit of multiplication of each type of fuel with unregulated and controlled supply associated with the adder connected to the fuel supply regulator, the actuator, the signal shaper when the pressure value of the superheated steam is mismatched, connected through the first integrator to the thermal load regulator, connected to the signal shaper of the current value of the thermal load and through the second integrator to the supply regulator t fuel, an additional computer and a multiplier are introduced, the output of the multiplying unit with controlled fuel supply connected to the input of the computer, the output of the computer connected to the output of the multiplier, the first output of the fuel supply regulator connected to the second input of the multiplier, and the second output of the fuel supply regulator to the second input of the calculator, and the output of the multiplier is connected to the input of the actuator. The introduced elements will allow forming a control action taking into account the feedback signal of the adjustable channel depending on the ratio of the mismatch to the feedback signal. Increases the dynamic accuracy of the regulation system.

 The drawing shows a structural diagram of the proposed device.

 It contains sensors 1 of the calorific value of each type of fuel, adjusters 2 of the calorific value of each type of fuel, driver 4 of the heat load signal, driver 5 of the signal mismatch pressure superheated steam; the first integrator 6, the multiplication unit 7, the second integrator 8, the adder 9, the fuel supply regulator 10, the actuator 11, the calculator 12, the multiplier 13 and the thermal load controller 14.

 The output of the sensor 1 of the calorific value of each type of fuel is connected to the inputs of the multiplication units 7 of the corresponding types of fuel. The outputs of the heat value adjusters 2 are connected to the corresponding inputs of the multiplication units 7. The outputs of the multiplication units 7 are connected to the inputs of the adder 9. The output of the fuel multiplying unit with adjustable feed is also connected to the input of the calculator 12. The output of the adder 9 is connected to the first input of the fuel supply controller 10 the first output of which is connected to the input of the multiplier 13, and the second output to the second input of the calculator 12. The first output of the multiplier 13 receives the first output of the controller, and the second input the output of the calculator 12. The output of the multiplier 13 under for prison the input actuator 11. The output of error signal generator 5 is connected by pressure to the input of the first inverter 6, whose output is connected to input controller 14 heat load. The output of the thermal load generator 4 is connected to the input of the thermal load controller 14, the output of which is connected to the input of the second integrator 8. The output of the second integrator 8 is connected to the second input of the fuel consumption controller 10.

 Sensors 1, switches 2 of the heat of combustion of each type of fuel generate signals, the multiplication of which in the multiplier corresponding to this type of fuel allows you to determine the amount of heat released by the corresponding type of fuel.

± ΔD_пп, где С_п постоянная, характеризующая массовую аккумулирующую способность пароводяной смеси и металла испарительной части котла, кг/(кгс/см²);
dP_б/dt скорость изменения давления пара в барабане;
ΔD_пп разность паровых нагрузок котла до и после нанесения возмущений по показаниям прибора, измеряющего расход перегретого пара.Shaper 4 signals the flow rate of the heat load 4 includes sensors for the flow of steam, the rate of change of steam pressure in the drum, a differentiator, an adder. The heat load signal is generated by the formula
ΔD _q = C _p

± ΔD _pp , where C _{p is a} constant characterizing the mass storage capacity of the steam-water mixture and the metal of the evaporative part of the boiler, kg / (kgf / cm ² );
dP _b / dt rate of change of vapor pressure in the drum;
ΔD _{pp the} difference between the steam loads of the boiler before and after disturbances according to the testimony of the device that measures the consumption of superheated steam.

 The signal generator 5 when the superheated steam pressure is mismatched includes a sensor and a superheated steam pressure adjuster connected to the input of the superheated steam pressure regulator. The superheated steam pressure regulator generates a control signal from the condition of minimum standard error.

 The first integrator 6 generates a signal for setting the heat load. The second integrator 8 generates a fuel feed reference signal.

 Adder 9 calculates the sum of all input signals and generates a signal of the total amount of heat generated by all types of fuel.

 The fuel supply controller 10 determines the mismatch between the set value and the current value of the heat generated by all types of fuel when they are currently burning. The received error signal feeds through its second output to the input of the calculator 12. At the first output of the fuel supply regulator 10 receives a signal generated by the PI control law.

 The actuator 11 is a dust collector motor and an electric signal amplifier. The output signal of the multiplier 13 is amplified and fed to the field winding of the electric motor (to the control device of the field winding). The speed of the electric motor determines the fuel consumption: the higher the speed, the greater the fuel consumption.

 The thermal load controller 14 compares the reference signal with the current thermal load signal and, when mismatched, generates a signal that minimizes the standard error of the thermal load.

K

+ 1

K

+ 1

, где К коэффициент;
U₇ количество теплоты, выделяемой при сжигании топлива с регулируемой подачей;
U_10.2 сигнал рассогласования заданной величины и величины обратной связи общего количества тепла, выделяемого при сжигании всех видов топлива.The input of the calculator 12 receives a signal of the amount of heat generated during the combustion of fuel with a regulated supply, and a signal of regulation error in the total amount of heat released during the combustion of all types of fuel. The output signal of the calculator is equal to the following value
U ₁₂ =

K

+ 1

K

+ 1

where K is the coefficient;
U _{7 the} amount of heat released during the combustion of fuel with a controlled flow;
U _10.2 mismatch signal of a given value and feedback value of the total amount of heat generated during the combustion of all types of fuel.

+ U_10.2= U₁₂·U_10.1, где U₁₂ выходной сигнал вычислителя 12;
U_10.1 выходной сигнал регулятора подачи топлива 10.The multiplier 13 finds the product between the values supplied to its input, and generates a signal fed to the input of the actuator
U ₁₃ =

+ U _10.2 = U ₁₂ · U _10.1 , where U _{12 the} output signal of the transmitter 12;
U _10.1 output signal of the fuel supply regulator 10.

When the heat load signal U ₄ deviates from the reference signal U _{6, the} output signal of the thermal load controller 14 is integrated by the integrator 8 and, in the form of a task, is fed to the input of the fuel supply controller 10.

 In a static state, the output signal of the superheated steam pressure regulator 5 (imbalance signal shaper) and from the output of the thermal load regulator 14 are equal to zero. The reference signals from the outputs of the first 6 and second 8 integrators are constant. The output signal of the calculator 12 is equal to one. The output signal of the multiplier 13 is equal to the output signal of the fuel supply controller 10.

 When the reference signal changes or when there is a disturbance due to a change in the heat load or a change in the total amount of heat generated by all types of fuel when they are burned, the signal from the second output of the fuel supply controller 10, supplied to the second input of the calculator 12, corresponds to a mismatch between the set and the actual value of the quantity heat generated by burning all types of fuel, and is non-zero. If this signal is positive, then the output signal of the calculator 12 is greater than unity and amplifies the output signal of the controller, and if negative, it is smaller than unity and reduces the value of the signal fed to the input of the actuator 11. The maximum value of the control action is limited by the maximum speed of the dust collector motor, which should be taken into account when selection of a motor speed control device. The introduced calculator 12, when forming the control action, allows taking into account not only the size of the mismatch between the task and the actual value of the controlled variable, but also the feedback signal of the adjustable parameter separately from the unregulated ones. With the same value of the mismatch signal, the regulatory effect will be the greater, the smaller the current feedback value of the adjustable channel, which will reduce the time for regulating the fuel supply and provide greater accuracy in maintaining (or regulating) the superheated steam pressure parameter.

 The proposed device improves the system performance. A more accurate maintenance of a given mode increases the efficiency of equipment that provides more accurate maintenance of an adjustable parameter (pressure), which reduces equipment wear during operation, reduces material costs for maintenance and overhaul.

Claims (1)

 SUPERHEATED VAPOR PRESSURE REGULATOR IN A MULTI-FUEL STEAM GENERATOR, containing sensors and adjusters associated with multipliers of each type of fuel with uncontrolled and controlled supply, connected to an adder connected to the fuel supply regulator, an actuator, a signal shaper when the pressure value is mismatched overheated steam, the first integrator with a heat load regulator connected to the signal shaper of the current value of the heat load and through the second integrator to the regulator a fuel supply regulator, characterized in that it has a calculator and a multiplier, wherein the output of the multiplying unit with controlled fuel supply is connected to the input of the calculator, the output of the calculator is connected to the input of the multiplier, the first output of the fuel supply regulator is connected to the second input of the multiplier, the second output of the fuel supply regulator connected to the second input of the calculator, and the output of the multiplier is connected to the input of the actuator.