Primary fan outlet air temperature control method and system

Abstract

The present application relates to the technical field of primary fans, and in particular to a primary fan outlet air temperature control method and system. It includes: obtaining the primary fan operating parameters, setting the hot primary air flow rate and the hot secondary air flow rate according to the primary fan operating parameters; setting the control parameters of the hot primary air according to the hot primary air flow rate, and setting the control parameters of the hot secondary air according to the hot secondary air flow rate; obtaining the real-time outlet air temperature data and ambient temperature data of the primary fan outlet, correcting the control parameters of the hot secondary air according to the ambient temperature, and correcting the control parameters of the hot primary air according to the real-time outlet air temperature data of the outlet. The primary air temperature at the outlet of the primary fan can also be increased by using the hot secondary air from the air preheater to the primary fan inlet. Reduce the fan energy consumption, because the secondary air pressure is much lower than the primary air pressure, and the secondary fan producing the same flow consumes much less energy than the primary fan. At the same time, the primary air volume can be guaranteed to meet the unit requirements by recycling the primary air with the hot secondary air.

Description

Technical Field

[0001] The present application relates to the technical field of primary fans, and in particular to a method and system for controlling the air outlet temperature of a primary fan. Background Art

[0002] At present, coal-fired thermal power plants are equipped with denitration systems due to environmental protection requirements. As environmental protection requirements become higher and higher, the NOx emission indicators of power plants are getting lower and lower, which leads to an increase in the amount of ammonia sprayed in the denitration system, ammonia escape control becomes worse, and the air preheater downstream of the denitration system produces more ammonium bisulfate. In a low temperature environment, ammonium bisulfate liquefies and mixes with fly ash, causing blockage of the air preheater. At the same time, many thermal power plants are running at low load, and the flue gas temperature is low, which is also one of the reasons for the low-temperature blockage of the air preheater.

[0003] Therefore, it is very important to increase the temperature of the air preheater. The primary fan has a large wind pressure and a fast flow rate, which is more likely to cause low temperature. The traditional method uses a hot primary air recirculation system to lead the hot primary air from the air preheater outlet to the primary fan inlet, thereby increasing the primary air temperature at the primary fan outlet, thereby increasing the temperature of the low-temperature end of the air preheater and avoiding the blockage of ammonium bisulfate. However, this traditional method has high energy consumption and will cause excessive cost waste. Summary of the invention

[0004] The purpose of this application is to solve the above technical problems and provide a primary fan outlet temperature control method and system, aiming to reduce the high energy consumption caused by the hot primary air recirculation system in the traditional way.

[0005] In some embodiments of the present application, the primary air temperature at the primary fan outlet can be increased by using hot secondary air from the air preheater to the primary fan inlet. The fan energy consumption is reduced because the secondary air pressure is much lower than the primary air pressure. The secondary fan consumes much less energy than the primary fan to produce the same flow rate. At the same time, the primary air can be recycled using hot secondary air to ensure that the primary air volume meets the unit requirements.

[0006] In some embodiments of the present application, by dynamically adjusting the ratio of hot primary air to hot secondary air, the air outlet temperature at the primary fan outlet is ensured to remain in a stable range, thereby avoiding blockage by ammonium bisulfate. At the same time, according to a preset program, the ratio of hot primary air is reduced, and the ratio of hot secondary air is increased, thereby reducing the overall operating energy consumption of the machine body.

[0007] In some embodiments of the present application, a method for controlling the air outlet temperature of a primary fan is provided, comprising:

[0008] Acquire the primary fan operating parameters, and set the hot primary air flow rate and the hot secondary air flow rate according to the primary fan operating parameters;

[0009] Set the control parameters of the primary hot air according to the primary hot air flow rate, and set the control parameters of the secondary hot air according to the secondary hot air flow rate;

[0010] Obtain the real-time air outlet temperature data and the ambient temperature data at the outlet of the primary air fan, correct the control parameters of the secondary hot air according to the ambient temperature, and correct the control parameters of the primary hot air according to the real-time air outlet temperature data at the outlet.

[0011] In some embodiments of the present application, when setting the primary hot air flow rate and the secondary hot air flow rate according to the operating parameters of the primary air fan, it includes:

[0012] Preset the primary air fan air outlet flow velocity matrix A, set A(A1, A2, A3, A4), where A1 is the preset first primary air fan air outlet flow velocity, A2 is the preset second primary air fan air outlet flow velocity, A3 is the preset third primary air fan air outlet flow velocity, A4 is the preset fourth primary air fan air outlet flow velocity, and A1 < A2 < A3 < A4;

[0013] Preset the primary hot air flow rate matrix B, set B(B1, B2, B3, B4), where B1 is the preset first primary hot air flow rate, B2 is the preset second primary hot air flow rate, B3 is the preset third primary hot air flow rate, B4 is the preset fourth primary hot air flow rate, and B1 < B2 < B3 < B4;

[0014] Obtain the real-time primary air fan air outlet flow velocity a, and set the real-time primary hot air flow rate b according to the real-time primary air fan air outlet flow velocity a:

[0015] If A1 < a < A2, set the real-time primary hot air flow rate b as the preset fourth primary hot air flow rate B4, that is, b = B4;

[0016] If A2 < a < A3, set the real-time primary hot air flow rate b as the preset third primary hot air flow rate B3, that is, b = B3;

[0017] If A3 < a < A4, set the real-time primary hot air flow rate b as the preset second primary hot air flow rate B2, that is, b = B2;

[0018] If a > A4, set the real-time primary hot air flow rate b as the preset first primary hot air flow rate B1, that is, b = B1.

[0019] In some embodiments of the present application, when setting the primary hot air flow rate and the secondary hot air flow rate according to the operating parameters of the primary air fan, it further includes:

[0020] Preset the hot secondary air flow matrix C, and set C(C1, C2, C3, C4), where C1 is the preset first hot secondary air flow, C2 is the preset second hot secondary air flow, C3 is the preset third hot secondary air flow, C4 is the preset fourth hot secondary air flow, and C1 < C2 < C3 < C4;

[0021] Set the real-time hot secondary air flow c according to the real-time hot primary air flow b;

[0022] If b = B1, set the real-time hot secondary air flow c as the preset fourth hot secondary air flow C4, that is, c = C4;

[0023] If b = B2, set the real-time hot secondary air flow c as the preset third hot secondary air flow C3, that is, c = C3;

[0024] If b = B3, set the real-time hot secondary air flow c as the preset second hot secondary air flow C2, that is, c = C2;

[0025] If b = B4, set the real-time hot secondary air flow c as the preset first hot secondary air flow C1, that is, c = C1.

[0026] In some embodiments of the present application, when setting the control parameters of the hot primary air according to the hot primary air flow, it includes:

[0027] Preset the outlet air temperature range D of the primary air fan, and set D(D1, D2), where D1 is the preset first outlet air temperature, D2 is the preset second outlet air temperature, and D1 < D2;

[0028] Obtain the real-time outlet air temperature d at the outlet of the primary air fan;

[0029] If D1 < d < D2, adjust the hot primary air flow b and the hot secondary air flow c, and stop adjusting when the hot primary air flow b = 0.

[0030] In some embodiments of the present application, when setting the control parameters of the hot primary air according to the hot primary air flow, it further includes:

[0031] Preset the hot primary air flow reduction rate matrix E, and set E(E1, E2, E3, E4), where E1 is the preset first hot primary air flow reduction rate, E2 is the preset second hot primary air flow reduction rate, E3 is the preset third hot primary air flow reduction rate, E4 is the preset fourth hot primary air flow reduction rate, and E1 < E2 < E3 < E4;

[0032] Set the real-time hot primary air flow reduction rate e according to the real-time hot primary air flow b;

[0033] If b < B1, set the reduction rate e of the real-time hot primary air flow as the preset fourth reduction rate E4 of the hot primary air flow, i.e., e = E4;

[0034] If B1 < b < B2, set the reduction rate e of the real-time hot primary air flow as the preset third reduction rate E3 of the hot primary air flow, i.e., e = E3;

[0035] If B2 < b < B3, set the reduction rate e of the real-time hot primary air flow as the preset second reduction rate E2 of the hot primary air flow, i.e., e = E2;

[0036] If B3 < b < B4, set the reduction rate e of the real-time hot primary air flow as the preset first reduction rate E1 of the hot primary air flow, i.e., e = E1.

[0037] In some embodiments of the present application, setting the control parameters of the hot secondary air according to the hot secondary air flow rate includes:

[0038] Preset a hot secondary air flow rate increase rate matrix F, set F(F1, F2, F3, F4), and F1 is the preset first hot secondary air flow rate increase rate, F2 is the preset second hot secondary air flow rate increase rate, F3 is the preset third hot secondary air flow rate increase rate, F4 is the preset fourth hot secondary air flow rate increase rate, and F1 < F2 < F3 < F4;

[0039] According to the real-time hot secondary air flow rate c, set the real-time hot secondary air flow rate increase rate f;

[0040] If C1 < c < C2, set the real-time hot secondary air flow rate increase rate f as the preset fourth hot secondary air flow rate increase rate F4, i.e., f = F4;

[0041] If C2 < c < C3, set the real-time hot secondary air flow rate increase rate f as the preset third hot secondary air flow rate increase rate F3, i.e., f = F3;

[0042] If C3 < c < C4, set the real-time hot secondary air flow rate increase rate f as the preset second hot secondary air flow rate increase rate F2, i.e., f = F2;

[0043] If c > C4, set the real-time hot secondary air flow rate increase rate f as the preset first hot secondary air flow rate increase rate F1, i.e., f = F1.

[0044] In some embodiments of the present application, when correcting the control parameters of the hot primary air according to the real-time air outlet temperature data, it includes:

[0045] Obtain the real-time air outlet temperature d1 at the outlet of the primary air fan during the adjustment process of the hot primary air flow rate and the hot secondary air flow rate;

[0046] If d1 < D1, obtain the temperature difference g between the real-time outlet air temperature d1 of the primary air fan and the preset first outlet air temperature D1, and correct the reduction rate e of the real-time hot primary air flow according to the difference g.

[0047] In some embodiments of the present application, when correcting the reduction rate e of the real-time hot primary air flow according to the difference g, it includes:

[0048] Preset a temperature difference matrix G, set G(G1, G2, G3), where G1 is the preset first temperature difference, G2 is the preset second temperature difference, G3 is the preset third temperature difference, and G1 < G2 < G3;

[0049] Preset a correction coefficient matrix N, set N(n1, n2, n3), where n1 is the preset first correction coefficient, n2 is the preset second correction coefficient, n3 is the preset third correction coefficient, and 0.7 < n1 < n2 < n3 < 1;

[0050] If g < G1, set the real-time correction coefficient n = n3, and the corrected reduction rate e of the real-time hot primary air flow is e = n3 * Ei;

[0051] If G1 < g < G2, set the real-time correction coefficient n = n2, and the corrected reduction rate e of the real-time hot primary air flow is e = n2 * Ei;

[0052] If G2 < g < G3, set the real-time correction coefficient n = n1, and the corrected reduction rate e of the real-time hot primary air flow is e = n1 * Ei.

[0053] In some embodiments of the present application, when correcting the control parameters of the hot secondary air according to the ambient temperature, it includes:

[0054] When the hot primary air flow b = 0, obtain the real-time ambient temperature t and the real-time hot secondary air flow c1;

[0055] Preset an ambient temperature matrix T, set T(T1, T2, T3, T4), where T1 is the preset first ambient temperature, T2 is the preset second ambient temperature, T3 is the preset third ambient temperature, T4 is the preset fourth ambient temperature, and T1 < T2 < T3 < T4;

[0056] Preset a compensation coefficient matrix M, set M(m1, m2, m3, m4), where 0.8 < m1 < m2 < 1 < m3 < m4 < 1.2;

[0057] If t < T1, set the real-time compensation coefficient m = m4, and the corrected real-time hot secondary air flow c2 = m4 * c1;

[0058] If T1 < t < T2, set the real-time compensation coefficient m = m3, and the corrected real-time hot secondary air flow rate c2 = m3 * c1;

[0059] If T2 < t < T3, do not correct the real-time hot secondary air flow rate c1;

[0060] If T3 < t < T4, set the real-time compensation coefficient m = m2, and the corrected real-time hot secondary air flow rate c2 = m2 * c1;

[0061] If t > T4, set the real-time compensation coefficient m = m1, and the corrected real-time hot secondary air flow rate c2 = m1 * c1.

[0062] In some embodiments of the present application, a primary air fan outlet air temperature control system is provided, including:

[0063] A central control unit, which is used to set the hot primary air flow rate and the hot secondary air flow rate according to the primary air fan operation parameters;

[0064] The central control unit is further used to set the control parameters of the hot primary air according to the hot primary air flow rate, and set the control parameters of the hot secondary air according to the hot secondary air flow rate;

[0065] A collection unit, which is used to collect the air outlet temperature data of the primary air fan outlet, and the central control unit and the collection unit are connected by a wireless signal;

[0066] The central control unit includes:

[0067] A first control module, which is used to control the real-time flow rate of the hot primary air;

[0068] A first correction module, which is used to correct the control parameters of the hot primary air according to the real-time air outlet temperature data of the outlet;

[0069] A second control module, which is used to control the real-time flow rate of the hot secondary air;

[0070] A second correction module, which is used to correct the control parameters of the hot secondary air according to the ambient temperature.

[0071] Compared with the prior art, the beneficial effects of the primary air fan outlet air temperature control method and system in the embodiments of the present application are as follows:

[0072] In some embodiments of the present application, by using the hot secondary air from the air preheater to the primary air fan inlet, the primary air temperature at the primary air fan outlet can also be increased. The fan energy consumption is reduced because the secondary air pressure is much lower than the primary air pressure, and the secondary air fan for producing the same flow rate consumes much less energy than the primary air fan. At the same time, by recycling the hot secondary air into the primary air, the primary air volume can be ensured to meet the unit requirements.

[0073] In some embodiments of the present application, by dynamically adjusting the ratio of hot primary air to hot secondary air, the air outlet temperature at the primary fan outlet is ensured to remain in a stable range, thereby avoiding blockage by ammonium bisulfate. At the same time, according to a preset program, the ratio of hot primary air is reduced, and the ratio of hot secondary air is increased, thereby reducing the overall operating energy consumption of the machine body. BRIEF DESCRIPTION OF THE DRAWINGS

[0074] Figure 1 It is a flow chart of a method for controlling the air outlet temperature of a primary fan in a preferred embodiment of the present application;

[0075] Figure 2 It is a schematic diagram of a primary fan outlet air temperature control system in a preferred embodiment of the present application. DETAILED DESCRIPTION

[0076] The specific implementation methods of the present application are further described in detail below in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present application but are not intended to limit the scope of the present application.

[0077] In the description of the present application, it should be understood that the terms "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0078] The terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, unless otherwise specified, "plurality" means two or more.

[0079] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0080] like Figure 1 As shown, a method for controlling the outlet air temperature of a primary fan in a preferred embodiment of the present application includes:

[0081] S101: Obtain the operating parameters of the primary air fan, and set the hot primary air flow rate and the hot secondary air flow rate according to the operating parameters of the primary air fan;

[0082] S102: Set the control parameters of the hot primary air according to the hot primary air flow rate, and set the control parameters of the hot secondary air according to the hot secondary air flow rate;

[0083] S103: Obtain the real-time outlet air temperature data and the ambient temperature data of the primary air fan outlet, correct the control parameters of the hot secondary air according to the ambient temperature, and correct the control parameters of the hot primary air according to the real-time outlet air temperature data.

[0084] Specifically, when setting the hot primary air flow rate and the hot secondary air flow rate according to the operating parameters of the primary air fan, it includes:

[0085] Preset the primary air fan outlet air velocity matrix A, and set A(A1, A2, A3, A4), where A1 is the preset first primary air fan outlet air velocity, A2 is the preset second primary air fan outlet air velocity, A3 is the preset third primary air fan outlet air velocity, A4 is the preset fourth primary air fan outlet air velocity, and A1 < A2 < A3 < A4;

[0086] Preset the hot primary air flow rate matrix B, and set B(B1, B2, B3, B4), where B1 is the preset first hot primary air flow rate, B2 is the preset second hot primary air flow rate, B3 is the preset third hot primary air flow rate, B4 is the preset fourth hot primary air flow rate, and B1 < B2 < B3 < B4;

[0087] Obtain the real-time primary air fan outlet air velocity a, and set the real-time hot primary air flow rate b according to the real-time primary air fan outlet air velocity a:

[0088] If A1 < a < A2, set the real-time hot primary air flow rate b as the preset fourth hot primary air flow rate B4, that is, b = B4;

[0089] If A2 < a < A3, set the real-time hot primary air flow rate b as the preset third hot primary air flow rate B3, that is, b = B3;

[0090] If A3 < a < A4, set the real-time hot primary air flow rate b as the preset second hot primary air flow rate B2, that is, b = B2;

[0091] If a > A4, set the real-time hot primary air flow rate b as the preset first hot primary air flow rate B1, that is, b = B1.

[0092] Specifically, when setting the hot primary air flow rate and the hot secondary air flow rate according to the operating parameters of the primary air fan, it also includes:

[0093] Preset the hot secondary air flow matrix C, set C(C1, C2, C3, C4), where C1 is the preset first hot secondary air flow, C2 is the preset second hot secondary air flow, C3 is the preset third hot secondary air flow, C4 is the preset fourth hot secondary air flow, and C1 < C2 < C3 < C4;

[0094] Set the real-time hot secondary air flow c according to the real-time hot primary air flow b;

[0095] If b = B1, set the real-time hot secondary air flow c as the preset fourth hot secondary air flow C4, that is, c = C4;

[0096] If b = B2, set the real-time hot secondary air flow c as the preset third hot secondary air flow C3, that is, c = C3;

[0097] If b = B3, set the real-time hot secondary air flow c as the preset second hot secondary air flow C2, that is, c = C2;

[0098] If b = B4, set the real-time hot secondary air flow c as the preset first hot secondary air flow C1, that is, c = C1.

[0099] Specifically, when the primary air fan starts to run, set the flow rate of the hot primary air and the hot secondary air according to its operating parameters, ensure that the outlet air temperature of the primary air fan quickly reaches a safe temperature range, and use the hot primary air and the hot secondary air to recycle the primary air once, which can ensure that the primary air volume meets the unit requirements and avoid the phenomenon of ammonium bisulfate blockage. At the same time, when the primary air fan starts to run, the proportion of the hot primary air participating in the primary air is higher than that of the hot secondary air, ensuring that the outlet of the primary air fan can be quickly heated.

[0100] In the preferred embodiment of this application, when setting the control parameters of the hot primary air according to the hot primary air flow rate, it includes:

[0101] Preset the outlet air temperature range D of the primary air fan, set D(D1, D2), where D1 is the preset first outlet air temperature, D2 is the preset second outlet air temperature, and D1 < D2;

[0102] Obtain the real-time outlet air temperature d of the primary air fan outlet;

[0103] If D1 < d < D2, adjust the hot primary air flow rate b and the hot secondary air flow rate c. When the hot primary air flow rate b = 0, stop adjusting.

[0104] Specifically, when setting the control parameters of the hot primary air according to the hot primary air flow rate, it also includes:

[0105] Preset the hot primary air flow rate reduction rate matrix E, and set E(E1, E2, E3, E4), where E1 is the preset first hot primary air flow rate reduction rate, E2 is the preset second hot primary air flow rate reduction rate, E3 is the preset third hot primary air flow rate reduction rate, E4 is the preset fourth hot primary air flow rate reduction rate, and E1 < E2 < E3 < E4;

[0106] According to the real-time hot primary air flow rate b, set the real-time hot primary air flow rate reduction rate e;

[0107] If b < B1, set the real-time hot primary air flow rate reduction rate e as the preset fourth hot primary air flow rate reduction rate E4, that is, e = E4;

[0108] If B1 < b < B2, set the real-time hot primary air flow rate reduction rate e as the preset third hot primary air flow rate reduction rate E3, that is, e = E3;

[0109] If B2 < b < B3, set the real-time hot primary air flow rate reduction rate e as the preset second hot primary air flow rate reduction rate E2, that is, e = E2;

[0110] If B3 < b < B4, set the real-time hot primary air flow rate reduction rate e as the preset first hot primary air flow rate reduction rate E1, that is, e = E1.

[0111] Specifically, when the outlet air temperature of the primary air fan is stable in the preset range, start to adjust the hot primary air flow rate to gradually reduce it. At the same time, through the preset hot primary air flow rate reduction rate matrix, adjust the reduction rate of the hot primary air in real time to avoid drastic changes in the outlet air temperature of the primary air fan caused by the adjustment of the hot primary air flow rate and ensure the stability of the system.

[0112] Specifically, set the control parameters of the hot secondary air according to the hot secondary air flow rate, including:

[0113] Preset the hot secondary air flow rate increase rate matrix F, and set F(F1, F2, F3, F4), and F1 is the preset first hot secondary air flow rate increase rate, F2 is the preset second hot secondary air flow rate increase rate, F3 is the preset third hot secondary air flow rate increase rate, F4 is the preset fourth hot secondary air flow rate increase rate, and F1 < F2 < F3 < F4;

[0114] According to the real-time hot secondary air flow rate c, set the real-time hot secondary air flow rate increase rate f;

[0115] If C1 < c < C2, set the real-time hot secondary air flow rate increase rate f as the preset fourth hot secondary air flow rate increase rate F4, that is, f = F4;

[0116] If C2 < c < C3, set the real-time increasing rate f of the hot secondary air flow as the preset third increasing rate F3 of the hot secondary air flow, i.e., f = F3;

[0117] If C3 < c < C4, set the real-time increasing rate f of the hot secondary air flow as the preset second increasing rate F2 of the hot secondary air flow, i.e., f = F2;

[0118] If c > C4, set the real-time increasing rate f of the hot secondary air flow as the preset first increasing rate F1 of the hot secondary air flow, i.e., f = F1.

[0119] Specifically, when the outlet air temperature of the primary air fan is stable within the preset range, start to adjust the hot secondary air flow to gradually increase it. At the same time, through the preset matrix of the increasing rate of the hot secondary air flow, the increasing rate of the hot secondary air flow is adjusted in real time to avoid the drastic change of the outlet air temperature of the primary air fan caused by the adjustment of the hot secondary air flow and ensure the stability of the system.

[0120] It can be understood that in the above embodiments, when the outlet air temperature of the primary air fan is stable, the hot primary air flow and the hot secondary air flow are dynamically adjusted through the preset matrix of the decreasing rate of the hot primary air flow and the preset matrix of the increasing rate of the hot secondary air flow until the hot secondary air completely replaces the hot primary air, reducing the overall operation energy consumption of the machine body.

[0121] In the preferred embodiment of the present application, when correcting the control parameters of the hot primary air according to the real-time outlet air temperature data of the air outlet, it includes:

[0122] Obtain the real-time outlet air temperature d1 of the primary air fan outlet during the adjustment process of the hot primary air flow and the hot secondary air flow;

[0123] If d1 < D1, obtain the temperature difference g between the real-time outlet air temperature d1 of the primary air fan outlet and the preset first outlet air temperature D1, and correct the real-time decreasing rate e of the hot primary air flow according to the difference g.

[0124] Specifically, when correcting the real-time decreasing rate e of the hot primary air flow according to the difference g, it includes:

[0125] Preset a temperature difference matrix G, set G(G1, G2, G3), where G1 is the preset first temperature difference, G2 is the preset second temperature difference, G3 is the preset third temperature difference, and G1 < G2 < G3;

[0126] Preset a correction coefficient matrix N, set N(n1, n2, n3), where n1 is the preset first correction coefficient, n2 is the preset second correction coefficient, n3 is the preset third correction coefficient, and 0.7 < n1 < n2 < n3 < 1;

[0127] If g < G1, set the real-time correction coefficient n = n3, and the reduced rate e of the real-time hot primary air flow after correction is e = n3 * Ei;

[0128] If G1 < g < G2, set the real-time correction coefficient n = n2, and the reduced rate e of the real-time hot primary air flow after correction is e = n2 * Ei;

[0129] If G2 < g < G3, set the real-time correction coefficient n = n1, and the reduced rate e of the real-time hot primary air flow after correction is e = n1 * Ei.

[0130] It can be understood that in the above embodiments, when the outlet air temperature of the primary air fan is stable in the preset interval, when adjusting the hot primary air and hot secondary air flows, the reduced rate of the real-time hot primary air flow is corrected through the preset correction coefficient and temperature difference matrix, avoiding drastic fluctuations in the temperature at the outlet of the primary air fan and ensuring the stability of the overall operation.

[0131] In the preferred embodiment of the embodiment of the present application, when correcting the control parameters of the hot secondary air according to the ambient temperature, it includes:

[0132] When the hot primary air flow b = 0, obtain the real-time ambient temperature t and the real-time hot secondary air flow c1;

[0133] Preset the ambient temperature matrix T, set T(T1, T2, T3, T4), where T1 is the preset first ambient temperature, T2 is the preset second ambient temperature, T3 is the preset third ambient temperature, T4 is the preset fourth ambient temperature, and T1 < T2 < T3 < T4;

[0134] Preset the compensation coefficient matrix M, set M(m1, m2, m3, m4), where 0.8 < m1 < m2 < 1 < m3 < m4 < 1.2;

[0135] If t < T1, set the real-time compensation coefficient m = m4, and the corrected real-time hot secondary air flow c2 = m4 * c1;

[0136] If T1 < t < T2, set the real-time compensation coefficient m = m3, and the corrected real-time hot secondary air flow c2 = m3 * c1;

[0137] If T2 < t < T3, do not correct the real-time hot secondary air flow c1;

[0138] If T3 < t < T4, set the real-time compensation coefficient m = m2, and the corrected real-time hot secondary air flow c2 = m2 * c1;

[0139] If t > T4, set the real-time compensation coefficient m = m1, and the corrected real-time hot secondary air flow c2 = m1 * c1.

[0140] It can be understood that in the above embodiment, when the hot secondary air completely replaces the hot primary air, the real-time ambient temperature is obtained, and the real-time hot secondary air flow rate is adjusted by setting the compensation coefficient to ensure the stability of its overall operation and appropriately reduce energy consumption.

[0141] like Figure 2 As shown, based on another embodiment of a primary fan outlet air temperature control method in any of the above preferred embodiments, this embodiment provides a primary fan outlet air temperature control system, including:

[0142] Central control unit, which is used to set the hot primary air flow rate and hot secondary air flow rate according to the primary fan operating parameters;

[0143] The central control unit is also used to set the control parameters of the hot primary air according to the hot primary air flow rate, and to set the control parameters of the hot secondary air according to the hot secondary air flow rate;

[0144] The collection unit is used to collect the air outlet temperature data of the primary fan. The central control unit and the collection unit are connected via wireless signals;

[0145] The central control unit includes:

[0146] A first control module, the first control module is used to control the real-time flow rate of hot primary air;

[0147] A first correction module, the first correction module is used to correct the control parameters of the hot primary air according to the real-time air outlet temperature data of the air outlet;

[0148] A second control module, the second control module is used to control the real-time flow rate of hot secondary air;

[0149] The second correction module is used to correct the control parameters of the hot secondary air according to the ambient temperature.

[0150] It can be understood that, in the above embodiment, the temperature of the primary air at the primary fan outlet can also be increased by using hot secondary air from the air preheater to the primary fan inlet. The energy consumption of the fan is reduced, because the secondary air pressure is much lower than the primary air pressure, and the secondary fan producing the same flow consumes much less energy than the primary fan. At the same time, by recycling the primary air with hot secondary air, it can be ensured that the primary air volume meets the needs of the unit. By dynamically adjusting the ratio of hot primary air and hot secondary air, the air outlet temperature at the primary fan outlet is maintained in a stable range to avoid blockage of ammonium bisulfate. At the same time, the proportion of hot primary air is reduced and the proportion of hot secondary air is increased according to the preset program, thereby reducing the overall operating energy consumption of the machine body.

[0151] The above is only a preferred implementation of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and substitutions can be made without departing from the technical principles of the present application. These improvements and substitutions should also be regarded as the scope of protection of the present application.

Claims

1. A method for controlling the air outlet temperature of a primary fan, characterized in that: Recycling primary air using hot primary air and hot secondary air, including: Obtaining the operating parameters of the primary air fan, and setting the hot primary air flow rate and the hot secondary air flow rate according to the operating parameters of the primary air fan; Setting the control parameters of the hot primary air according to the hot primary air flow rate, and setting the control parameters of the hot secondary air according to the hot secondary air flow rate; Obtaining the real-time outlet air temperature data of the primary air fan and the ambient temperature data, correcting the control parameters of the hot secondary air according to the ambient temperature, and correcting the control parameters of the hot primary air according to the real-time outlet air temperature data.

2. The primary fan outlet temperature control method according to claim 1, characterized in that: When setting the hot primary air flow rate and the hot secondary air flow rate according to the operating parameters of the primary air fan, it includes: Presetting the primary air fan outlet air velocity matrix A, setting A(A1, A2, A3, A4), where A1 is the preset first primary air fan outlet air velocity, A2 is the preset second primary air fan outlet air velocity, A3 is the preset third primary air fan outlet air velocity, A4 is the preset fourth primary air fan outlet air velocity, and A1 < A2 < A3 < A4; Presetting the hot primary air flow rate matrix B, setting B(B1, B2, B3, B4), where B1 is the preset first hot primary air flow rate, B2 is the preset second hot primary air flow rate, B3 is the preset third hot primary air flow rate, B4 is the preset fourth hot primary air flow rate, and B1 < B2 < B3 < B4; Obtaining the real-time primary air fan outlet air velocity a, and setting the real-time hot primary air flow rate b according to the real-time primary air fan outlet air velocity a: If A1 < a < A2, setting the real-time hot primary air flow rate b as the preset fourth hot primary air flow rate B4, that is, b = B4; If A2 < a < A3, setting the real-time hot primary air flow rate b as the preset third hot primary air flow rate B3, that is, b = B3; If A3 < a < A4, setting the real-time hot primary air flow rate b as the preset second hot primary air flow rate B2, that is, b = B2; If a > A4, setting the real-time hot primary air flow rate b as the preset first hot primary air flow rate B1, that is, b = B1.

3. The primary fan outlet temperature control method according to claim 2, characterized in that: When setting the hot primary air flow rate and the hot secondary air flow rate according to the operating parameters of the primary air fan, it also includes: Presetting the hot secondary air flow rate matrix C, setting C(C1, C2, C3, C4), where C1 is the preset first hot secondary air flow rate, C2 is the preset second hot secondary air flow rate, C3 is the preset third hot secondary air flow rate, C4 is the preset fourth hot secondary air flow rate, and C1 < C2 < C3 < C4; Setting the real-time hot secondary air flow rate c according to the real-time hot primary air flow rate b; If b = B1, setting the real-time hot secondary air flow rate c as the preset fourth hot secondary air flow rate C4, that is, c = C4; If b = B2, setting the real-time hot secondary air flow rate c as the preset third hot secondary air flow rate C3, that is, c = C3; If b = B3, setting the real-time hot secondary air flow rate c as the preset second hot secondary air flow rate C2, that is, c = C2; If b = B4, setting the real-time hot secondary air flow rate c as the preset first hot secondary air flow rate C1, that is, c = C1.

4. The primary fan outlet temperature control method according to claim 2, characterized in that: When setting the control parameters of the hot primary air according to the hot primary air flow rate, it includes: Preset the outlet air temperature range D of the primary air fan, set D(D1, D2), where D1 is the preset first outlet air temperature, D2 is the preset second outlet air temperature, and D1 < D2; Obtain the real-time outlet air temperature d of the primary air fan outlet; If D1 < d < D2, adjust the hot primary air flow rate b and the hot secondary air flow rate c. When the hot primary air flow rate b = 0, stop the adjustment.

5. The primary fan outlet temperature control method according to claim 4, characterized in that: When setting the control parameters of the hot primary air according to the hot primary air flow rate, it further includes: Preset the hot primary air flow rate reduction rate matrix E, set E(E1, E2, E3, E4), where E1 is the preset first hot primary air flow rate reduction rate, E2 is the preset second hot primary air flow rate reduction rate, E3 is the preset third hot primary air flow rate reduction rate, E4 is the preset fourth hot primary air flow rate reduction rate, and E1 < E2 < E3 < E4; Set the real-time hot primary air flow rate reduction rate e according to the real-time hot primary air flow rate b; If b < B1, set the real-time hot primary air flow rate reduction rate e as the preset fourth hot primary air flow rate reduction rate E4, that is, e = E4; If B1 < b < B2, set the real-time hot primary air flow rate reduction rate e as the preset third hot primary air flow rate reduction rate E3, that is, e = E3; If B2 < b < B3, set the real-time hot primary air flow rate reduction rate e as the preset second hot primary air flow rate reduction rate E2, that is, e = E2; If B3 < b < B4, set the real-time hot primary air flow rate reduction rate e as the preset first hot primary air flow rate reduction rate E1, that is, e = E1.

6. The primary fan outlet air temperature control method according to claim 5, characterized in that: Setting the control parameters of the hot secondary air according to the hot secondary air flow rate includes: Preset the hot secondary air flow rate increase rate matrix F, set F(F1, F2, F3, F4), and F1 is the preset first hot secondary air flow rate increase rate, F2 is the preset second hot secondary air flow rate increase rate, F3 is the preset third hot secondary air flow rate increase rate, F4 is the preset fourth hot secondary air flow rate increase rate, and F1 < F2 < F3 < F4; Set the real-time hot secondary air flow rate increase rate f according to the real-time hot secondary air flow rate c; If C1 < c < C2, set the real-time hot secondary air flow rate increase rate f as the preset fourth hot secondary air flow rate increase rate F4, that is, f = F4; If C2 < c < C3, set the real-time hot secondary air flow rate increase rate f as the preset third hot secondary air flow rate increase rate F3, that is, f = F3; If C3 < c < C4, set the real-time hot secondary air flow rate increase rate f as the preset second hot secondary air flow rate increase rate F2, that is, f = F2; If c > C4, set the real-time hot secondary air flow rate increase rate f as the preset first hot secondary air flow rate increase rate F1, that is, f = F1.

7. The primary fan outlet temperature control method according to claim 6, characterized in that: When correcting the control parameters of the hot primary air according to the real-time outlet air temperature data of the outlet, it includes: Obtain the real-time outlet air temperature d1 of the primary air fan outlet during the adjustment process of the hot primary air flow rate and the hot secondary air flow rate; If d1 < D1, obtain the temperature difference g between the real-time outlet air temperature d1 of the primary air fan and the preset first outlet air temperature D1, and correct the reduction rate e of the real-time hot primary air flow according to the difference g.

8. The primary fan outlet air temperature control method according to claim 6, characterized in that: When correcting the control parameters of the hot secondary air according to the ambient temperature, it includes: When the hot primary air flow b = 0, obtain the real-time ambient temperature t and the real-time hot secondary air flow c1; Preset an ambient temperature matrix T, set T(T1, T2, T3, T4), where T1 is the preset first ambient temperature, T2 is the preset second ambient temperature, T3 is the preset third ambient temperature, T4 is the preset fourth ambient temperature, and T1 < T2 < T3 < T4; Preset a compensation coefficient matrix M, set M(m1, m2, m3, m4), where 0.8 < m1 < m2 < 1 < m3 < m4 < 1.2; If t < T1, set the real-time compensation coefficient m = m4, and the corrected real-time hot secondary air flow c2 = m4 * c1; If T1 < t < T2, set the real-time compensation coefficient m = m3, and the corrected real-time hot secondary air flow c2 = m3 * c1; If T2 < t < T3, do not correct the real-time hot secondary air flow c1; If T3 < t < T4, set the real-time compensation coefficient m = m2, and the corrected real-time hot secondary air flow c2 = m2 * c1; If t > T4, set the real-time compensation coefficient m = m1, and the corrected real-time hot secondary air flow c2 = m1 * c1.

9. A primary fan outlet temperature control system, using the primary fan outlet temperature control method according to any one of claims 1 to 8, characterized in that: It includes: A central control unit, which is used to set the hot primary air flow and the hot secondary air flow according to the operating parameters of the primary air fan; The central control unit is also used to set the control parameters of the hot primary air according to the hot primary air flow, and set the control parameters of the hot secondary air according to the hot secondary air flow; An acquisition unit, which is used to acquire the outlet air temperature data of the primary air fan, and the central control unit and the acquisition unit are connected by a wireless signal; The central control unit includes: A first control module, which is used to control the real-time flow of the hot primary air; A first correction module, which is used to correct the control parameters of the hot primary air according to the real-time outlet air temperature data; A second control module, which is used to control the real-time flow of the hot secondary air; A second correction module, which is used to correct the control parameters of the hot secondary air according to the ambient temperature.

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