CN-122002649-A - PTC heater with PWM controller and wide linearity characteristic

Abstract

The invention discloses a PTC heater with a PWM controller and wide linearity, relates to the technical field of electric heating, and aims to solve the problems of insufficient linearity of power output and PWM duty ratio, limited power regulation range and high control complexity of the traditional PTC heater. The heater comprises a PTC heating module and a PWM controller, wherein the PTC heating module is composed of a plurality of PTC heating elements, the resistance range and the Curie temperature of the PTC heating elements are optimized, the quantity of the PTC heating elements is reasonably matched, the PTC heater can stably and accurately adjust power within the range of 0-100% of PWM duty ratio, the linear characteristic is obviously improved, a complex control circuit or algorithm is not needed, the system cost and the design difficulty are reduced, and the heater is suitable for various heating scenes requiring high-precision power adjustment.

Inventors

• WANG WEI
• YAN QIUSHI
• WU ZHOULI
• LIAO YI
• WU JIAMING

Assignees

• 孝感华工高理电子有限公司

Dates

Publication Date

20260508

Application Date

20260224

Claims (9)

1. 1. A PTC heater with a PWM controller and wide linearity is characterized by comprising a PTC heating module and a PWM controller electrically connected with the PTC heating module; the PTC heating module consists of a plurality of PTC heating elements, so that a heating function is realized; The PWM controller controls the wide linear characteristic of the PTC heating element according to a preset PTC heating element wide linear characteristic control table.
2. 2. The PTC heater according to claim 1, wherein the preset PTC heating element wide linearity characteristic control table specifically comprises a linear relationship of the resistance value, curie temperature and output power of the PTC heating element within the range of 0-100% of the duty cycle of the PWM controller under the same test environment.
3. 3. A PTC heater according to claim 2, wherein the same test environment comprises in particular test voltage and wind speed conditions.
4. 4. A PTC heater according to claim 2, wherein the linear relation between the resistance value, the Curie temperature and the output power of the PTC heating element comprises that the larger the resistance value of the PTC heating element is, the higher the Curie temperature is, and the stronger the linear characteristic of the power output along with the change of PWM duty ratio is.
5. 5. The PTC heater according to claim 2, wherein the PTC heating element has a linear relation between the resistance value, the Curie temperature and the output power of the PTC heating element in the range of 0-100% of the duty ratio of the PWM controller under the same test environment, specifically comprises the resistance value range of 5-6kΩ, the Curie temperature of 170-190 ℃, and the PTC heater can realize power regulation in the range of 0-100% of the duty ratio of the PWM under the conditions that the working voltage is 350VDC and the test wind speed is 5m/s, and the output power is 750w under the duty ratio of 100%.
6. 6. A PTC heater according to claim 5, wherein the PTC heating elements constituting the PTC heating module are 17 in number when the resistance of the PTC heating elements is 5-5.5kΩ and the curie temperature is 170 ℃.
7. 7. A PTC heater according to claim 5, wherein the PTC heating elements are 15 in number when the resistance of the PTC heating elements is 5.4-6kΩ, the curie temperature is 190 ℃.
8. 8. A PTC heater according to claim 1, wherein the PWM controller is adapted to output PWM control signals of different duty cycles to regulate the power output of the PTC heating module.
9. 9. A PTC heater according to claim 1, wherein the PTC heating element is made of a positive temperature coefficient semiconductor ceramic material.

Description

PTC heater with PWM controller and wide linearity characteristic Technical Field The invention relates to the technical field of electric heating, in particular to a PTC heater with a PWM controller and wide linearity. Background PTC (positive temperature coefficient) heaters are widely used in various fields such as home appliances, automobiles, industrial heating, etc., by virtue of their unique self-temperature limiting characteristics. The working principle of the PTC heater is to realize automatic temperature control by utilizing the characteristic that the resistance of the PTC material increases sharply when the temperature rises, so that the overheat phenomenon is avoided. However, the conventional PTC heater has many disadvantages in practical application. The most prominent of these is the weak linear relationship of the power output to the PWM (pulse width modulation) control signal. Under the condition of low PWM duty ratio, the power output of the traditional PTC heater is seriously insufficient and cannot meet the low-power heating requirement, while under the condition of high PWM duty ratio, the power change is too sensitive and fine power adjustment is difficult to realize, so that the traditional PTC heater is difficult to play a role in the scene of needing high-precision power control. Further analysis shows that the resistance design of the conventional PTC heater is relatively fixed, and research and development personnel cannot fully realize the important influence of the resistance on the linear characteristic of the power output, so that the power regulation range is greatly limited. In order to realize wide-range power regulation, the prior art often needs to design a complex control circuit or adopt a complex control algorithm, which not only increases the manufacturing cost of the system, but also increases the design difficulty and the later maintenance cost, and is not beneficial to popularization and application of the PTC heater. Disclosure of Invention The invention aims to solve at least one technical problem existing in the prior art and provides a PTC heater with a PWM controller and wide linearity. In a first aspect, an embodiment of the present invention provides a PTC heater with a PWM controller having a wide linear characteristic, including a PTC heating module and a PWM controller electrically connected to the PTC heating module; the PTC heating module consists of a plurality of PTC heating elements, so that a heating function is realized; The PWM controller controls the wide linear characteristic of the PTC heating element according to a preset PTC heating element wide linear characteristic control table. Further, the preset PTC heating element wide linear characteristic control table specifically comprises a linear relation of the resistance value, curie temperature and output power of the PTC heating element within the range of 0-100% of the duty ratio of the PWM controller under the same test environment. Further, the same test environment specifically includes test voltage and wind speed conditions. Further, the linear relation between the resistance value, the Curie temperature and the output power of the PTC heating element specifically comprises that the larger the resistance value of the PTC heating element is, the higher the Curie temperature is, and the stronger the linear characteristic of the power output along with the change of the PWM duty ratio is. Further, under the same test environment, the PTC heating element has a linear relation between the resistance value, the Curie temperature and the output power of the PTC heating element within the range of 0-100% of the duty ratio of the PWM controller, and specifically comprises the PTC heating element with the resistance value range of 5-6kΩ and the Curie temperature of 170-190 ℃, wherein under the conditions that the working voltage is 350VDC and the test wind speed is 5m/s, the PTC heater can realize power adjustment within the range of 0-100% of the duty ratio of the PWM, and the output power is 750w under the duty ratio of 100%. Further, when the resistance value of the PTC heating elements is 5 to 5.5kΩ and the curie temperature is 170 ℃, the number of PTC heating elements constituting the PTC heating module is 17. Further, when the resistance value of the PTC heating elements is 5.4-6kΩ, the curie temperature is 190 ℃, and the number of PTC heating elements constituting the PTC heating module is 15. Further, the PWM controller is configured to output PWM control signals of different duty cycles to regulate the power output of the PTC heating module. Further, the PTC heating element is made of a semiconductor ceramic material with positive temperature coefficient. The invention discloses a PTC heater with a PWM controller and wide linearity, relates to the technical field of electric heating, and aims to solve the problems of insufficient linearity of power output and PWM duty ratio, limited powe