Induction heating power supply water circulation cooling system and self-adaptive control method

Abstract

The invention discloses an induction heating power supply water circulation cooling system and an adaptive control method, and the method comprises the steps: 1) a console issues a control parameter p of an induction heating power supply, and a water circulation system obtains the parameter at the same time; 2) a power consumption prediction model in the water circulation cooling system predicts power consumption P0 to be generated by the induction heating power supply system according to historical parameters when the given value is p; 3) the power consumption prediction model reversely deduces the required cooling water flow Q according to the prediction result P0; 4) according to the flow Q, obtaining a frequency f required by the operation of the frequency converter so as to drive the frequency converter to work; 5) detecting the voltage u, the current i and the temperature value T fed back by the induction heating power supply system in real time by the power prediction model, and correcting f in real time, and 6) storing all parameters p, u, i, P0 and f. According to the invention, the power consumption of the system can be predicted in advance according to the change of the power of the induction heating power supply, then the cooling circulation device is adaptively and synchronously adjusted, and correction is carried out according to the real-time change of the temperature.

Description

Technical Field

[0001] The invention relates to the technical field of high-frequency induction heating power supplies, and in particular to an induction heating power supply water circulation cooling system and an adaptive control method. Background Art

[0002] In recent years, with the increasing attention paid to industrial energy-saving transformation and carbon emission issues, induction heating power supplies have been increasingly widely used in industrial fields such as large-capacity steel, metallurgy, and metal heat treatment. High-power induction heating power supply systems usually operate at the megawatt level, and their power devices have a high switching frequency, which will generate a lot of heat loss. If the circulating cooling treatment is not carried out in time, the power device will fail or even the entire system will collapse. Therefore, the circulating cooling system in the induction heating system is particularly important. The commonly used cold cutting method is the water circulation cooling system. The core components of the induction power supply system are installed on the water-cooled heat sink. The external water circulation system provides cooling circulating water to the induction power supply to quickly take away the heat generated by the core components during operation, thereby ensuring the stable operation of the system.

[0003] Existing water circulation cooling devices are divided into two control modes: (1) constant flow control and (2) variable flow control. Constant flow control is the simplest control mode. It always supplies circulating water at a constant flow rate regardless of the working state of the induction heating system. Although this method can ensure that the system will not overheat to the greatest extent, it will cause a large amount of water and electricity resources to be wasted. Variable flow control can flexibly adjust the water supply according to the actual temperature conditions, thereby achieving energy conservation, emission reduction and optimal resource utilization. However, traditional variable flow control performs flow control based on the detected temperature value, and temperature feedback has a certain lag, and may not be able to respond effectively in time when the temperature fluctuates greatly or an emergency occurs. Summary of the invention

[0004] The purpose of the present invention is to overcome the defects of the prior art and provide an induction heating power supply water circulation cooling system and an adaptive control method, which can predict the power consumption of the system in advance according to the change of the induction heating power supply power, and then adaptively adjust the cooling circulation device synchronously, and then make corrections according to the real-time change of temperature.

[0005] The purpose of the present invention is achieved in one aspect as follows: an adaptive control method for an induction heating power supply water circulation cooling system comprises the following steps:

[0006] 1) The control console sends the control parameter p of the induction heating power supply, and the induction heating power supply sends the given value p to the water circulation cooling system synchronously through the CAN bus;

[0007] 2) The power consumption prediction model in the water circulation cooling system predicts the power consumption P0 that the induction heating power supply system will generate when p is given based on historical parameters;

[0008] 3) The power consumption prediction model reversely calculates the required cooling water flow Q based on the prediction result P0;

[0009] 4) According to the flow rate Q, the frequency f required for the inverter to work is obtained, thereby driving the inverter to work;

[0010] 5) The power prediction model detects the voltage u, current i, and temperature value T fed back by the induction heating power supply system in real time; and corrects f in real time;

[0011] 6) Save all parameters p, u, i, P0, f as the data basis for subsequent predictions;

[0012] 7) After completing one synchronization adjustment, repeat steps 1) to 6) and wait for the next adjustment.

[0013] As a further limitation of the present invention, the calculation formula of the power P0 in step 2) is P0=f(p,u,t,T).

[0014] As a further limitation of the present invention, the cooling water flow rate Q in step 3) is obtained according to the following formula:

[0015] Q=P0 / Cp*ρ*ΔT0

[0016] Where Cp is the specific heat capacity of water 4.2*10 3 J / kg·℃, ρ is 1*10 3 kg / m 3 , ΔT0 is the predicted temperature rise value.

[0017] As a further limitation of the present invention, the real-time correction f in step 5) specifically includes: defining the difference between the two detected temperature values ​​T as the actual temperature rise value ΔT1, comparing the predicted temperature rise value ΔT0 with the actual temperature rise value ΔT1, if ΔT1-ΔT0≤d, d is the allowable error, it is considered that the requirements are met; if ΔT1-ΔT0>d, then fine-tuning the control parameter f of the inverter.

[0018] Another aspect of the purpose of the present invention is achieved as follows: an induction heating power supply water circulation cooling system, including a control console, an induction heating power supply, a frequency converter and a water pump, and a power consumption prediction model history parameter module;

[0019] The control console is used to send the control parameter p of the induction heating power supply, and the induction heating power supply synchronously sends the given value p to the power consumption prediction model of the water circulation cooling system through the CAN bus;

[0020] The power consumption prediction module predicts the power consumption P0 that the induction heating power supply system will generate when a given value is p based on the historical parameter module; reversely infers the required cooling water flow Q based on the prediction result P0; obtains the frequency f required for the inverter to work based on the flow Q, thereby driving the inverter and the water pump to work; and simultaneously detects the voltage u, current i, and temperature value T fed back by the induction heating power supply system in real time; and corrects f in real time.

[0021] The induction heating power supply feeds back the voltage u, current i and temperature value T to the power consumption prediction model according to the water flow Q output by the frequency converter and the water pump;

[0022] The historical parameter module is used to save the parameters output by the parameter power consumption prediction model, further improve the historical database, and optimize the power consumption prediction model.

[0023] As a further limitation of the present invention, the induction heating power supply includes a three-phase thyristor rectifier, an H-bridge inverter and a resonant load;

[0024] The power supply line side is a three-phase thyristor phase-controlled rectifier, and a filter circuit composed of L0 and C0 and a DC smoothing reactor L are connected between the three-phase thyristor phase-controlled rectifier and the H-bridge inverter. d The H-bridge resonant inverter is connected in parallel with a resonant load, wherein the resonant load is a capacitor C and an inductor L. r An LC type parallel resonant circuit is formed.

[0025] The present invention adopts the above technical solution, and the beneficial effects compared with the prior art are: 1) cost saving: the device and control method proposed in the present invention can adjust the flow rate of cooling water in a targeted manner according to the output power of the induction heating power supply to achieve precise control, thereby achieving the purpose of saving water and electricity costs.

[0026] 2) Fast response time: Compared with the traditional temperature hysteresis variable flow control method, the system and method proposed by the present invention can adjust the water flow in advance by predicting when the power of the induction heating power source changes, thus avoiding the problem of being unable to respond effectively in time to emergencies.

[0027] 3) Strong adaptive capability: The system and method proposed in the present invention can update and improve the prediction model in real time through online learning methods, thereby realizing the ability of online self-evolution. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 System principle diagram of the present invention.

[0029] Figure 2 Schematic diagram of the high-frequency induction heating power supply system according to the present invention. DETAILED DESCRIPTION

[0030] like Figure 1 An induction heating power supply water circulation cooling system shown includes a control console, an induction heating power supply, and is characterized in that it also includes a frequency converter and a water pump, and a power consumption prediction model historical parameter module;

[0031] The control console is used to send the control parameter p of the induction heating power supply. The induction heating power supply sends the given value p to the power consumption prediction model of the water circulation cooling system synchronously through the CAN bus.

[0032] The power consumption prediction module predicts the power consumption P0 that the induction heating power supply system will generate when the historical parameter module is given as p; the required cooling water flow Q is reversed based on the prediction result P0; the frequency f required for the inverter to work is obtained based on the flow Q, thereby driving the inverter and the water pump to work; at the same time, the voltage u, current i, and temperature value T fed back by the induction heating power supply system are detected in real time; and f is corrected in real time.

[0033] The induction heating power supply feeds back the voltage u, current i, and temperature value T to the power consumption prediction model according to the water flow Q output by the inverter and the water pump;

[0034] The historical parameter module is used to save the parameters output by the parameter power consumption prediction model, further improve the historical database, and optimize the power consumption prediction model.

[0035] The induction heating power supply includes a three-phase thyristor rectifier, an H-bridge inverter and a resonant load; the power supply line side is a three-phase thyristor phase-controlled rectifier, and a filter circuit composed of L0 and C0 and a DC smoothing reactor L are connected between the three-phase thyristor phase-controlled rectifier and the H-bridge inverter. d The H-bridge resonant inverter is connected in parallel with a resonant load, wherein the resonant load is a capacitor C and an inductor L. r An LC type parallel resonant circuit is formed.

[0036] An adaptive control method for an induction heating power supply water circulation cooling system comprises the following steps:

[0037] 1) The control console sends the control parameter p of the induction heating power supply, and the induction heating power supply sends the given value p to the water circulation cooling system synchronously through the CAN bus;

[0038] 2) The power consumption prediction model in the water circulation cooling system predicts the loss P0 that will be generated by the induction heating power supply at this time based on the relationship between historical parameters and P0 = f(p,u,t,T);

[0039] 3) The power consumption prediction model uses the result P0 predicted in step 2) and the formula Q = P0 / Cp*ρ*ΔT0 to obtain the cooling water flow rate under the current loss, where Cp is the specific heat capacity of water (4.2*103J / kg.℃), ρ is 1*103kg / m3, and ΔT0 is the predicted temperature rise value;

[0040] 4) According to the water flow value Q calculated in step 3, the QH curve of the water pump is looked up to obtain the speed n of the water pump at this time. At this time, the power consumption prediction model gives the control parameter f=F(n) of the water pump frequency conversion. At this operating frequency, the flow rate of the water pump can meet the requirements of step 3);

[0041] 5) The power prediction model detects the voltage u, current i and temperature value T fed back by the induction heating power supply system in real time; corrects f in real time; defines the difference between the two detected temperature values ​​T as the actual temperature rise value ΔT1, compares the predicted temperature rise value ΔT0 with the actual temperature rise value ΔT1, if ΔT1-ΔT0≤d, d is the allowable error, it is considered to meet the requirements; if ΔT1-ΔT0>d, fine-tune the control parameter f of the inverter.

[0042] 6) Save all parameters p, u, i, P0, f, so as to further improve the historical database and optimize the power consumption prediction model;

[0043] 7) After completing one synchronization adjustment, repeat steps 1) to 6) and wait for the next adjustment.

[0044] like Figure 2 As shown in FIG. 1 , (a) is the induction heating power supply system of the present invention. It is mainly composed of a three-phase thyristor rectifier, an H-bridge inverter and a resonant load; the power supply line side is a three-phase thyristor phase-controlled rectifier, which plays a role in regulating the power supply, and the filter circuit composed of L0 and C0 can smooth the DC output voltage of the thyristor. d It is a DC smoothing reactor, providing a constant current source for the H-bridge resonant inverter. The resonant load side is capacitor C and inductor L. r The LC parallel resonant circuit is formed to provide heating power for the heated steel strip. (b) is an induction heating power supply cooling system according to the present invention, which mainly provides external circulating water for the thyristor, H-bridge inverter and resonant capacitor radiator in the induction heating power supply system.

[0045] The control flow is:

[0046] 1) The production line control center sends an instruction of operating parameter p=500kw to the induction heating power supply according to the process requirements. The induction heating power supply sends the instruction of given value 500kw to the water circulation control system synchronously through the CAN bus;

[0047] 2) The induction heating power supply adjusts the phase angle of the thyristor to make the power output meet the requirement of 500kw. At the same time, the power consumption prediction model predicts the power consumption P0=10%*p based on the historical data and the relationship between P0=f(p,u,t,T), that is, the induction heating power supply is expected to produce a loss of P0=50kw under this power.

[0048] 3) According to step 2), P0 = 50kw, set the maximum allowable temperature rise ΔT0 = 10 degrees, and then according to the formula Q = P0 / Cp*ρ*ΔT0, the required cooling water flow rate Q = 72L / min can be obtained at this time;

[0049] 4) Calculate the pump speed n = 1200 rpm when Q = 72 L / min based on the QH curve provided by the pump manufacturer, and then obtain the inverter speed command f = 35 Hz based on the rated speed of the pump;

[0050] 5) The AD sampling module collects the operating parameters of the induction heating power supply, voltage u, current i, and temperature rise value ΔT1 in real time, and compares the predicted temperature rise value ΔT0 with the actual temperature rise value ΔT1. If ΔT1-ΔT0≤d, d=3 degrees, it is considered to meet the requirements; if ΔT1-ΔT0>d, the control parameters of the inverter are fine-tuned from f=f+Δf;

[0051] 6) Save all parameters p, u, i, P0 and f;

[0052] 7) After completing one synchronization adjustment, repeat steps 1) to 6) and wait for the next adjustment.

[0053] The present invention is not limited to the above-mentioned embodiments. On the basis of the technical solution disclosed in the present invention, technicians in this field can make some substitutions and deformations to some technical features therein according to the disclosed technical content without creative labor, and these substitutions and deformations are all within the protection scope of the present invention.

Claims

1. An adaptive control method for an induction heating power supply water circulation cooling system, characterized in that: The following steps are involved: 1) The control console sends the control parameter p of the induction heating power supply, and the induction heating power supply sends the given value p to the water circulation cooling system synchronously through the CAN bus; 2) The power consumption prediction model in the water circulation cooling system predicts the power consumption P0 that the induction heating power supply system will generate when p is given based on historical parameters; 3) The power consumption prediction model reversely calculates the required cooling water flow Q based on the prediction result P0; 4) According to the flow rate Q, the frequency f required for the inverter to work is obtained, thereby driving the inverter to work; 5) The power prediction model detects the voltage u, current i, and temperature value T fed back by the induction heating power supply system in real time; and corrects f in real time; 6) Save all parameters p, u, i, P0, f as the data basis for subsequent predictions; 7) After completing one synchronization adjustment, repeat steps 1) to 6) and wait for the next adjustment.

2. The adaptive control method of an induction heating power supply water circulation cooling system according to claim 1 is characterized in that: The calculation formula of the power P0 in step 2) is P0=f(p,u,t,T).

3. The adaptive control method of an induction heating power supply water circulation cooling system according to claim 1, characterized in that: The cooling water flow rate Q in step 3) is obtained according to the following formula: Q=P0 / Cp*ρ*ΔT0 Where Cp is the specific heat capacity of water 4.2*10 3 J / kg·℃, ρ is 1*10 3 kg / m 3 , ΔT0 is the predicted temperature rise value.

4. The adaptive control method of an induction heating power supply water circulation cooling system according to claim 1, characterized in that: The real-time correction f in step 5) specifically includes: defining the difference between the two detected temperature values ​​T as the actual temperature rise value ΔT1, comparing the predicted temperature rise value ΔT0 with the actual temperature rise value ΔT1, if ΔT1-ΔT0≤d, d is the allowable error, it is considered that the requirements are met; if ΔT1-ΔT0>d, then fine-tuning the control parameter f of the inverter.

5. An induction heating power supply water circulation cooling system, comprising a control console and an induction heating power supply, characterized in that: It also includes modules for historical parameters of frequency converters, water pumps, and power consumption prediction models; The control console is used to send the control parameter p of the induction heating power supply, and the induction heating power supply synchronously sends the given value p to the power consumption prediction model of the water circulation cooling system through the CAN bus; The power consumption prediction module predicts the power consumption P0 that the induction heating power supply system will generate when the historical parameter module is given as p; reversely infers the required cooling water flow Q based on the prediction result P0; obtains the frequency f required for the inverter to work based on the flow Q, thereby driving the inverter and the water pump to work; and simultaneously detects the voltage u, current i, and temperature value T fed back by the induction heating power supply system in real time; and corrects f in real time; The induction heating power supply feeds back the voltage u, current i and temperature value T to the power consumption prediction model according to the water flow Q output by the frequency converter and the water pump; The historical parameter module is used to save the parameters output by the parameter power consumption prediction model, further improve the historical database, and optimize the power consumption prediction model.

6. The induction heating power supply water circulation cooling system according to claim 1, characterized in that: The induction heating power supply includes a three-phase thyristor rectifier, an H-bridge inverter and a resonant load; The power supply line side is a three-phase thyristor phase-controlled rectifier, and a filter circuit composed of L0 and C0 and a DC smoothing reactor L are connected between the three-phase thyristor phase-controlled rectifier and the H-bridge inverter. d The H-bridge resonant inverter is connected in parallel with a resonant load, wherein the resonant load is a capacitor C and an inductor L. r An LC type parallel resonant circuit is formed.

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