WO2018028407A1

WO2018028407A1 - Multi-element induction stove and power control method therefor

Info

Publication number: WO2018028407A1
Application number: PCT/CN2017/093561
Authority: WO
Inventors: 李民; 武永强
Original assignee: 深圳拓邦股份有限公司
Priority date: 2016-08-10
Filing date: 2017-07-19
Publication date: 2018-02-15
Also published as: CN106247416B; CN106247416A

Abstract

A multi-element induction stove and a power control method therefor, the multi-element induction stove comprises an operation panel and a control unit; and the power control method comprises the following steps: S1, in accordance with a user's selection, acquiring a target power P_n and the maximum power P_nmax of each element of at least two elements during operation, the maximum power P_nmax of each element being the same, that is, P_nmax=P_max; S2, calculating a total target power P = ΣP_n of the multi-element induction stove according to the target power P_n; S3, controlling the actual output power of each element according to the relative sizes of the total target power P and the maximum power P_max. The multi-element induction stove power control method can effectively prevent noise generated by the induction stove working at different target power and is not limited by an electromagnetic induction coil of the element. Each element can achieve a desired target operating power, and power switch loss can be effectively reduced.

Description

Multi-cooker induction cooker and power control method thereof

Technical field

The present invention relates to the field of electromagnetic heating technology, and more particularly to a multi-cooker induction cooker and a power control method thereof.

Background technique

In the field of electromagnetic heating technology, the application range of multi-cooker induction cooker is more and more wide, but when multiple stoves work at the same time, the power of each stove is not consistent, and its working frequency is also different. Although the default operating frequency of each cooktop is usually outside the hearing range of the human ear, the operating frequency difference between the cooktops easily falls into the hearing range of the human ear, generating noise that the user can hear, affecting the user experience. The prior art 1 (application number: CN201210279872.7) discloses a heating control method for a multi-head electromagnetic cooker. By working in a certain period T, each stove head is operated in turn at a target power P, and the calculation method of the working time is t=P. /∑P*T. Prior Art 2 (Application No. CN200680023003.0) discloses a method of providing power to a plurality of induction coils, the plurality of induction coils alternately operating in the same frequency and difference frequency modes. The above two methods can prevent the generation of interference noise to a certain extent, but the power that the induction coil can sense in the prior art 1 must be several times the maximum power of the multi-cooker (for example, N times for the N-cup) , causing a great waste of the capacity of the induction coil, and the withstand voltage of the resonant capacitor is very high, which is extremely unfavorable for the selection of the device and the stability of the product; in the prior art 2, the difference frequency and the same frequency are mutually converted to work. When using the difference frequency operation, since the working frequency is higher than the resonant frequency, the power of the coil is generally low. Therefore, when the target power is large, the difference frequency operation is difficult to reach the target power, and Existing The problem in technique 1.

Summary of the invention

The technical problem to be solved by the present invention is to provide a multi-cooker induction cooker and a power control method thereof against the defects of the prior art, which avoids noise generated due to inconsistent operating frequencies of the cooktops.

The technical solution adopted by the present invention to solve the technical problem thereof is to provide a power control method for a multi-cooker induction cooker, the method comprising the following steps:

S1: obtaining, according to a user selection, a target power _Pn and a maximum power _{Pnmax of} each stovehead when at least two stoves are working, wherein the maximum power _{Pnmax of} each stovehead is the same, that is, _Pnmax = _Pmax ;

S2: The calculation of the target power P _n of the total multi target power burner of the appliance P = ΣP _n;

S3: Control an actual output power of each of the stoves according to a magnitude relationship between the total target power P and the maximum power _Pmax .

Preferably, the step S3 comprises the following steps:

S31: determining whether the total target power P is greater than the maximum power P _max , if yes, proceeding to step S33, otherwise executing S32;

S32: when P≤P _max , the stoves work in turn with the total target power P, and when one of the stoves is working, the other stoves do not work;

S33: When P>P _max , each of the stoves respectively operates at different frequencies; the difference between the frequencies exceeds the hearing range of the human ear.

Preferably, the step S32 comprises the following steps:

S321: setting a working period T _{1 of} the multi-cooker induction cooker;

S322: calculating the duty cycle of each burner in the time T ₁ to the total target operating power P _{_{t n1 = P n / P *}} T 1;

S323: Control the corresponding stove work according to the working time t _n1 .

Preferably, the step S33 comprises the following steps:

S331: setting a duty cycle T _{2 of} the multi-cooker induction cooker to a target frequency difference Δf, f ₁ ≤ Δf ≤ f ₂ ;

S332: Acquire a frequency f _1a when one of the cooktops operates at the maximum power P _max , and an operating frequency f _2b of another stove that is simultaneously operated to reach the total target power;

Obtaining a frequency f _2a when the other stove head is operated at a maximum power P _max , and an operating frequency f _{1b of the} one of the stoves simultaneously operating to reach the total target power;

Calculate the frequency difference Δf ₁ =f _2b -f _1a and Δf ₂ =f _1b -f _2a between the two burners working at the same time;

S333: determining whether the frequency difference Δf ₁ and Δf ₂ are within the range of the target frequency difference Δf, and if yes, executing step S334, otherwise performing step S335;

S334: time calculation for each burner to the maximum power P _max T ₂ operating in the working cycle:

Go to step S336;

S335: adjusting the working frequency of the two stoves working at the same time, proceeds to step S333;

S336: Control the corresponding stove work according to the working time t _n2 .

Preferably, the step S335 comprises the following steps:

S335a: when Δf ₁ > f ₂ or Δf ₂ > f ₂ , keeping the total target power P constant, adjusting the values of f _1a and f _2b , f _1b and f _2a such that f ₁ ≤ Δf ₁ ≤ f ₂ , f ₁ ≤ Δf ₂ ≤ f ₂ , proceeds to step S333;

S335b: When Δf ₁ <f ₁ or Δf ₂ <f ₁ , comparing the frequency at which the two burners operating at the same time operate at the target power P _n , a smaller value f _{n is obtained} , and the two stoves are controlled to f _n Work at the same frequency and adjust the duty cycle of one of the burners.

Preferably, the step S335a comprises the following steps:

A1: reducing the values of f _2b and f _1b to f _2B and f _1B ;

A2: The values of f _1a and f _2a are increased to f _1A and f _2A , and the total target power P is kept constant so that f ₁ ≤ Δf ₁ ≤ f ₂ , f ₁ ≤ Δf ₂ ≤ f ₂ .

Preferably, the target frequency difference ranges from 16 KHz ≤ Δf ≤ 26 KHz.

The present invention also provides a multi-cooker induction cooker using the above control method, comprising:

Operation panel: used to select the target power of the working cooker and the cooktop;

The control unit: The user selects, acquires at least two burner stove operation of each of the target power P _n and the maximum power P _nmax, the same maximum power of the burner in each P _nmax, i.e. P _nmax = P _max; in accordance with the calculating a target power P _n of the multi-burner induction cooker total target power P = ΣP _n; the size relationship between the power P and the target total maximum power P _max, the actual output power control of each burner .

Preferably, the controlling the actual output power of each of the stoves comprises: when P≤P _max , the stoves are operated in turn at a total target power P, and when one of the stoves is working, the other stoves are not working; When P>P _max , each of the stoves respectively operates at different frequencies; the difference Δf between the frequencies exceeds the hearing range of the human ear.

Preferably, the difference between the frequencies ranges from 16 KHz ≤ Δf ≤ 26 KHz.

The multi-chasing induction cooker power control method embodying the invention can effectively avoid the noise generated by each stove head working under different target powers, is not limited by the electromagnetic induction coil in the stove head, and each stove head can reach the required target working power, and Effectively reduce the loss of the power switch.

DRAWINGS

The present invention will be further described below in conjunction with the accompanying drawings and embodiments, in which:

Figure 1 is a flow chart of the control method of the present invention;

Figure 2 is a schematic diagram of the working cycle of a cooktop in the case of P ≤ P _max ;

Figure 3 is a schematic view showing the working cycle of another cooktop in the working state shown in Figure 2;

Figure 4 is a schematic diagram of the duty cycle of a cooktop in the case of P > P _max ;

Fig. 5 is a schematic view showing the working cycle of another cooking head in the working state shown in Fig. 3.

detailed description

The multi-chasing cooker power control method and the multi-chasing cooker according to the embodiment of the present invention are described below with reference to the accompanying drawings.

As shown in FIG. 1, the power control method of the multi-cooker induction cooker proposed by the present invention comprises the following steps:

S1: The user selects, acquires at least two burner stove operation of each of the target power P _n and the maximum power P _nmax, the same maximum power per burner P _nmax, i.e. P _nmax = P _max;

S2: P _n is calculated according to the target power multi-burner induction cooker total target power P = ΣP _n;

S3: Control the actual output power of each cooktop according to the relationship between the total target power P and the maximum power _Pmax .

Further, step S3 includes the following steps:

S31: determining whether the total target power P is greater than the maximum power P _max , if yes, executing step S33, otherwise executing S32;

S32: When P≤P _max , each stove head works in turn with the total target power P, and when one of the stoves is working, the other stoves do not work;

S33: When P>P _max , each stove head operates together at different frequencies; the difference between the frequencies exceeds the hearing range of the human ear.

When the stoves are in turn, it is possible to avoid noise generated by different frequencies when the stoves are working at the same time. When each stove is operated at different frequencies, the difference between the frequencies of the stoves exceeds the hearing of the human ear. The range can also effectively reduce the impact of noise on the user.

Further, step S32 includes the following steps:

S321: setting a working period T _{1 of the} multi-cooker induction cooker;

S322: calculating the work time of each burner to the total target power P in the work cycle _{_{_{T 1 t n1 = P n /}}} P * T 1;

Further, step S33 includes the following steps:

S331: setting the working period T _{2 of the} multi-cooker induction cooker to the target frequency difference Δf, f ₁ ≤ Δf ≤ f ₂ ;

S333: determining whether the frequency difference Δf ₁ and Δf ₂ are within the range of the target frequency difference Δf, if yes, executing step S334, otherwise performing step S335;

S334: Calculation time for each burner to the maximum power P _max T ₂ operating in the working cycle:

Go to step S336;

In some embodiments, since the difference frequency noise of the multi-cooker induction cooker is usually generated due to the difference frequency operation of the adjacent cooktops, and the two far-distance cookers operating at a different distance are less likely to generate noise that can be heard by the human ear, the above-mentioned The power control method in the embodiment is preferably applied to the case where exactly two burners work at the same time.

In some embodiments, when the three stoves are working at the same time, the positions of the three stoves can be determined first. If each of the stoves is far apart, the work can be directly performed. If two of the stoves are in close proximity, the power is controlled as described above; If the three stoves are adjacent and the sum of the target powers of the two adjacent stoves is greater than the maximum power, the working frequency can be compared by the above method to ensure that the frequency difference between the two stoves is in the range of the human ear audible range. Outside.

Further, step S33 includes the following steps:

To make the frequency difference within the target frequency difference range, adjust f _2b , f _1b or increase f _1a , f _2a , or decrease f _2b , f _1b and increase f _1a , f _2a . Since the default minimum operating frequency of each cooktop is usually greater than or equal to the resonant frequency f ₀ when the induction cooker is designed, when Δf ₁ = f _2b - f _1a > f ₂ , f _2b > f ₂ + f _{0 is known} . Since the operating frequency f _{2b of the cooktop is} far away from the resonant frequency, the power variation that can be caused by continuing to adjust the frequency is relatively small. Thus, the value of f _2b may be set to _{_{_{f 2b = f 2 + f 0}}} , f _1a and then adjusted based on this, the target that the total power P constant. Similarly, the adjustment methods for f _1b and f _2a are the same as the adjustment methods for f _2b and f _1a described above.

S335b: When Δf ₁ <f ₁ or Δf ₂ <f ₁ , comparing the frequency at which the two burners operating at the same time work at the target power P _n , a smaller value f _{n is obtained} , and the two burners are controlled to operate at the same frequency as f _n . And adjust the duty cycle of one of the stoves.

In this case, by adjusting the PWM to achieve the adjustment of the output power, the operating frequency of each cooktop of the induction cooker is uniform, achieving a noise-free effect.

The present invention provides a multi-cooker induction cooker that should use the above control method, the induction cooker comprising an operation panel and a control unit:

The control unit: According to user selection, operation of each acquiring at least two burner stove target power P _n and P _nmax maximum power, the maximum power of each of the P _nmax same burner, i.e. P _nmax = P _max; in accordance with the target power P _n Calculate the total target power P=∑P _{n of the} multi-cooker induction cooker; control the actual output power of each cooktop according to the magnitude relationship between the total target power P and the maximum power P _max .

Since the difference frequency noise of the multi-cooker induction cooker usually occurs when the difference frequency operation of the adjacent cooktops is generated, and the two stoves that are far away from each other are not easy to generate noise easily heard by the human ear, the above power control method preferably It is applied to the case where two stoves work at the same time. Preferably, the induction cooker in some embodiments of the present invention is a double cooktop induction cooker, the double cooktop comprising a first cooktop and a second cooktop. The user selects the first stove and the second stove to work simultaneously through the operation panel of the induction cooker and sets the target power of both.

As shown in FIG. 2 and FIG. 3, specifically, in an embodiment of the present invention, the target power of the user selecting the first stove and the second stove is P ₁ =1500 W and P ₂ =1000 W, respectively. The rated maximum power of each stove is equal to 2500W, that is, P _1max = P _2max = P _max = 2500W; the preset duty cycle T ₁ = 400ms. By calculation, the total target power of the induction cooker P = ∑ P _n = P ₁ + P ₂ = 2500 W = P _max . In this case, the first cooktop and the second cooktop operate in turn at a total target power P, and when one of the cooktops is in operation, the other cooktop does not work. Based on the above information, the time t ₁₁ = P ₁ /P * T ₁ = 1500/2500 * 400 = 240 ms at which the first cook head is operated with the power P during the duty cycle T ₁ is calculated. The time t ₁₂ = P ₂ / P * T ₁ = 1000/2500 * 400 = 160 ms at which the second cook head is operated with the power P during the duty cycle T ₁ is calculated. The first burner and the second burner turns work within _a work cycle _{_{T, T 1 = t 11 +}} t 12. The induction cooker control unit controls the corresponding stove head according to the calculated power and time.

As shown in FIG. 4 and FIG. 5, specifically, in an embodiment of the present invention, the target power of the user selecting the first stove and the second stove is P ₁ =2000 W and P ₂ =1000 W, respectively. The rated maximum power of each cooktop is equal to 2500W, that is, P _1max = P _2max = P _max = 2500W; the preset duty cycle T ₂ = 400ms; the range of the target frequency difference Δf is set in an inaudible area of the human ear, this embodiment The preferred range is 16 KHz ≤ Δf ≤ 26 KHz. By calculation, the total target power of the induction cooker P = ∑ P _n = P ₁ + P ₂ = 3000 W > P _max . In this case, the first cooktop and the second cooktop operate together and operate in turn at maximum power _Pmax , respectively. When one of the cooktops is operated at power _Pmax , the operating power of the other cooktop is _PPmax . Calculating the frequency f _1a when the first stove head is operated at the maximum power P _max and the operating frequency f _2b of the second stove head according to the above information; calculating the frequency f _2a when the second stove head is operated at the maximum power P _max , and The operating frequency f _1b of the first burner; the frequency difference Δf ₁ = f _2b - f _1a and Δf ₂ = f _1b - f _{2a in the} two operating states; if both Δf ₁ and Δf ₂ are within the target frequency difference , calculating the time at which the first stove head operates at the power P _max during the duty cycle T ₂

Calculating a second time period T hob work ₂ work at a power P _max

The first burner and the second burner in a co-operating working cycle _{_{_{T 2, T 2 = t 12}}} + t 22. The induction cooker control unit controls the corresponding stove head according to the calculated power and time.

In some embodiments, a case where Δf ₁ > f ₂ or Δf ₂ > f ₂ occurs, in which case the total target power P should be kept constant, and the values of f _1a and f _2b , f _1b and f _2a are adjusted so that f ₁ ≤ Δf ₁ ≤ f ₂ , f ₁ ≤ Δf ₂ ≤ f ₂ ; in particular, the default minimum operating frequency of each cooktop is usually greater than or equal to the resonant frequency f ₀ , preferably the resonant frequency f ₀ = 20 KHz, so when Δf ₁ When =f _2b -f _1a >26KHz, it is known that f _2b >46KHz. Since the operating frequency f _{2b of the cooktop is} far away from the resonant frequency, the power variation that can be caused by continuing to adjust the frequency is relatively small. Thus, the value of f _2b may be set to f _2b = 46KHz, f _1a and then adjusted based on this, the target that the total power P constant. Similarly, the adjustment methods for f _1b and f _2a are the same as the adjustment methods for f _2b and f _1a described above.

In some embodiments, a Δf ₁ <f ₁ or Δf ₂ <f ₁ condition may occur, in which case the first cooktop and the second cooktop may operate at the same frequency. Specifically, the frequency at which the first stove and the second stove are respectively operated at respective target powers is calculated, and the two are compared to obtain a smaller frequency value, and both of the stoves operate at the smaller frequency value. In this case, by adjusting the PWM to achieve the adjustment of the output power, the operating frequency of each cooktop of the induction cooker is uniform, achieving a noise-free effect.

It is to be understood that the above-described embodiments are merely illustrative of the preferred embodiments of the present invention, and are not to be construed as limiting the scope of the invention; The above technical features may be freely combined, and various modifications and improvements may be made without departing from the spirit and scope of the invention; therefore, the scope of the claims of the present invention is Equivalent transformations and modifications are intended to be included within the scope of the appended claims.

Claims

A power control method for a multi-cooker induction cooker, characterized in that the method comprises the following steps:

S1: obtaining, according to a user selection, a target power Pn and a maximum power Pnmax of each stovehead when at least two stoves are working, wherein the maximum power Pnmax of each stovehead is the same, that is, Pnmax = Pmax ;

S2: The calculation of the target power P n of the total multi target power burner of the appliance P = ΣP n;

S3: Control an actual output power of each of the stoves according to a magnitude relationship between the total target power P and the maximum power Pmax .
The method of claim 1 wherein said step S3 comprises the steps of:

S31: determining whether the total target power P is greater than the maximum power P max , if yes, proceeding to step S33, otherwise executing S32;

S32: when P≤P max , the stoves work in turn with the total target power P, and when one of the stoves is working, the other stoves do not work;

S33: When P>P max , each of the stoves respectively operates at different frequencies; the difference between the frequencies exceeds the hearing range of the human ear.
The method of claim 2 wherein said step S32 comprises the steps of:

S321: setting a working period T 1 of the multi-cooker induction cooker;

S322: calculating the duty cycle of each burner in the time T 1 to the total target operating power P t n1 = P n / P * T 1;

S323: Control the corresponding stove work according to the working time t n1 .
The method of claim 2 wherein said step S33 comprises the steps of:

S331: setting a duty cycle T 2 of the multi-cooker induction cooker to a target frequency difference Δf, f 1 ≤ Δf ≤ f 2 ;

S332: Acquire a frequency f 1a when one of the cooktops operates at the maximum power P max , and an operating frequency f 2b of another stove that is simultaneously operated to reach the total target power;

Obtaining a frequency f 2a when the other stove head is operated at a maximum power P max , and an operating frequency f 1b of the one of the stoves simultaneously operating to reach the total target power;

Calculate the frequency difference Δf 1 =f 2b -f 1a and Δf 2 =f 1b -f 2a between the two burners working at the same time;

S333: determining whether the frequency difference Δf 1 and Δf 2 are within the range of the target frequency difference Δf, and if yes, executing step S334, otherwise performing step S335;

S334: time calculation for each burner to the maximum power P max T 2 operating in the working cycle:
Go to step S336;

S335: adjusting the working frequency of the two stoves working at the same time, proceeds to step S333;

S336: Control the corresponding stove work according to the working time t n2 .
The method according to claim 4, wherein said step S335 comprises the following steps:

S335a: when Δf 1 > f 2 or Δf 2 > f 2 , keeping the total target power P constant, adjusting the values of f 1a and f 2b , f 1b and f 2a such that f 1 ≤ Δf 1 ≤ f 2 , f 1 ≤ Δf 2 ≤ f 2 , proceeds to step S333;

S335b: When Δf 1 <f 1 or Δf 2 <f 1 , comparing the frequency at which the two burners operating at the same time operate at the target power P n , a smaller value f n is obtained , and the two stoves are controlled to f n Work at the same frequency and adjust the duty cycle of one of the burners.
The method of claim 5 wherein said step S335a comprises the steps of:

A1: reducing the values of f 2b and f 1b to f 2B and f 1B ;

A2: The values of f 1a and f 2a are increased to f 1A and f 2A , and the total target power P is kept constant so that f 1 ≤ Δf 1 ≤ f 2 , f 1 ≤ Δf 2 ≤ f 2 .
The method according to claim 4, wherein said target frequency difference ranges from 16 KHz ≤ Δf ≤ 26 KHz.
A multi-cooker induction cooker using the above control method, comprising:

Operation panel: used to select the target power of the working cooker and the cooktop;

The control unit: The user selects, acquires at least two burner stove operation of each of the target power P n and the maximum power P nmax, the same maximum power of the burner in each P nmax, i.e. P nmax = P max; in accordance with the calculating a target power P n of the multi-burner induction cooker total target power P = ΣP n; the size relationship between the power P and the target total maximum power P max, the actual output power control of each burner .
The multi-burner induction cooker of claim 8, characterized in that the control of the actual output power of each burner comprises: when P≤P max, each of said burner power P total target rotation operation, when When one of the stoves is working, the other stoves are not working; when P>P max , the stoves are operated together at different frequencies; the difference Δf between the frequencies exceeds the hearing range of the human ear.
The multi-cooker induction cooker according to claim 9, wherein the difference between the frequencies ranges from 16 KHz ≤ Δf ≤ 26 KHz.