Anti-interference silicon controlled rectifier drive circuit
By connecting high-voltage ceramic chip capacitors and parallel ceramic chip capacitors in series in the Thyristor drive circuit, absorbing and processing EFT pulses, the problem of microconduction of the Thyristor drive circuit prone to occur under strong EFT interference is solved, and the circuit is significantly improved reliability and anti-interference ability.
Patent Information
- Application Number
- CN202420279396.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-02-05
- Publication Date
- 2025-02-14
- Estimated Expiration
- 2034-02-05
AI Technical Summary
Existing thyristor drive circuits are prone to microconduction under strong EFT interference, resulting in adverse phenomena such as heating, abnormal motor rotation, and even burning of the entire machine.
An anti-interference thyristor driver circuit is designed, which absorbs high-voltage ceramic chip capacitors by connecting the transistor E-pole of the control circuit in series between the T1 pole of the thyristor and the ceramic chip capacitors in parallel between the transistor B pole and the E pole of the control circuit. Process high voltage, high frequency EFT pulses.
It effectively protects thyristors and control devices, avoids high-voltage breakdown and microconductivity, improves the reliability and anti-interference ability of the circuit, and can pass 5KV EFT testing.
Smart Images
Figure CN222484681U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to a driving circuit, in particular to an anti-interference silicon controlled rectifier driving circuit. Background Art
[0002] There are many small household appliances on the market that use thyristors for speed and temperature control. However, there are also frequent cases of micro-conduction of thyristors under strong EFT interference, which heats up for no reason, causes motor rotation, and burns shaded-pole motors. To prevent such undesirable phenomena and improve product safety, many manufacturers have raised the EFT (electronic pulse group) test standard from the national standard 1kv to 4kv, and even require a high anti-interference level of 5kv, and cover pulse frequencies of 5KHz and 100KHz. However, the current thyristor drive circuit can only meet the national standard in many cases. In a complex market environment, abnormalities occur frequently. Due to the limited withstand voltage of thyristors and related control devices, micro-conduction phenomena are everywhere, so thyristors explode and the whole machine burns out. Utility Model Content
[0003] In view of the shortcomings of the prior art, the utility model proposes an anti-interference thyristor driving circuit with a simple circuit structure. By cleverly setting a capacitor loop, the high-voltage and high-frequency EFT pulses can be absorbed and processed to ensure that the thyristor and control device will not be broken down by high voltage or have micro-conduction phenomenon.
[0004] In order to realize the above technical scheme, the utility model provides an anti-interference thyristor driving circuit, including: capacitors C341, C342; driving resistors; resistors R345, R346; transistor Q340; thyristor T340 and load HEAT, wherein the T1 pole of the thyristor T340 is connected to the capacitor C341 and the ACL-AC of the power supply respectively, the other end of the capacitor C341 is connected to the E pole of the transistor Q340 and then grounded, the T2 pole of the thyristor T340 is connected to one end of the load HEAT, and the load HEAT The other end of AT is connected to the ACN of the power supply, the control electrode G electrode of the thyristor T340 is connected to one end of the driving resistor, the other end of the driving resistor is connected to the C electrode of the transistor Q340, the B electrode of the transistor Q340 is respectively connected to one end of the capacitor C342, the resistor R345, and the R346, the other end of the capacitor C342 is connected to the E electrode of the transistor Q340 and then grounded, the other end of the resistor R346 is connected to the E electrode of the transistor Q340 and then grounded, and the other end of the resistor R345 is connected to the I / O port of the MCU.
[0005] In the above technical solution, a high-voltage ceramic capacitor C341 is connected in series between the T1 pole (i.e., pin 1) of the thyristor T340 and the E pole of the transistor Q340 of the control circuit, and a ceramic capacitor C342 is connected in parallel between the B pole of the control transistor Q340 and the E pole of the transistor Q340, so that the high-voltage and high-frequency EFT pulses generated in the drive circuit can be absorbed and processed to ensure that the thyristor and the control device will not be broken down by the high voltage or micro-conduction will occur.
[0006] Preferably, the anti-interference thyristor drive circuit further includes a capacitor C340, resistors R340 and R341, wherein one end of the capacitor C340 is connected to the line connecting the capacitor C341 and the power supply ACL-AC, the other end of the capacitor C340 is connected to the resistor R340, the other end of the resistor R340 is connected to the resistor R341, and the other end of the resistor R341 is connected to the line connecting the T2 pole of the thyristor T340 and the load HEAT. In actual use, by connecting an RC bypass composed of the capacitor C340, the resistors R340 and R341 in parallel between the thyristor T1 pole (pin 1) and the T2 pole (pin 2), the high voltage and high frequency EFT pulses generated in the drive circuit can be further absorbed and processed, thereby improving the overall anti-interference performance of the drive circuit.
[0007] Preferably, the driving resistor is formed by resistors R342 and R343 connected in parallel.
[0008] The beneficial effects of an anti-interference thyristor drive circuit provided by the utility model are as follows: the anti-interference thyristor drive circuit has a simple structure, and absorbs high-voltage and high-frequency EFT pulses through an ingenious circuit loop, thereby protecting the thyristor and control devices from being broken down by EFT and avoiding micro-conduction, greatly improving the reliability of the circuit, preventing abnormal rotation or heating of the motor, avoiding burning of the entire machine, and improving the service life and reliability of the product. It can effectively pass the 5KV EFT test and improve the reliability of the drive circuit. BRIEF DESCRIPTION OF THE DRAWINGS
[0009] Figure 1 This is a circuit diagram of the utility model. DETAILED DESCRIPTION
[0010] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. All other embodiments obtained by ordinary personnel in this field without creative work are within the scope of protection of the utility model.
[0011] Embodiment: An anti-interference thyristor driving circuit.
[0012] Reference Figure 1 As shown, an anti-interference thyristor drive circuit includes: capacitors C340, C341, C342; resistors R340, R341, R342, R343, R345, R346; transistor Q340; thyristor T340 and load HEAT, wherein the T1 pole (pin 1) of the thyristor T340 is connected to the capacitor C341 and the ACL-AC of the power supply respectively, the other end of the capacitor C341 is connected to the E pole of the transistor Q340 and then grounded, and a high-voltage ceramic capacitor C341 is connected in series between the T1 pole (i.e., pin 1) of the thyristor T340 and the E pole of the transistor Q340 of the control loop, and the capacitor C341 can effectively absorb the high-voltage and high-frequency EFT pulses generated in the drive circuit, thereby improving the overall anti-interference ability of the circuit;
[0013] The T2 pole (pin 2) of the thyristor T340 is connected to one end of the load HEAT, the other end of the load HEAT is connected to the ACN of the power supply, one end of the capacitor C340 is connected to the line connecting the capacitor C341 and the power supply ACL-AC, the other end of the capacitor C340 is connected to the resistor R340, the other end of the resistor R340 is connected to the resistor R341, and the other end of the resistor R341 is connected to the line connecting the T2 pole of the thyristor T340 and the load HEAT; in actual use, by connecting an RC bypass composed of the capacitor C340, the resistors R340 and R341 in parallel between the thyristor T1 pole (pin 1) and the T2 pole (pin 2), the high voltage and high frequency EFT pulse generated in the drive circuit can be further absorbed and processed, thereby improving the overall anti-interference performance of the drive circuit;
[0014] The control electrode G of the thyristor T340 is connected to one end of the driving resistor, and the driving resistor is formed by connecting resistors R342 and R343 in parallel. The other end of the driving resistor is connected to the C electrode of the transistor Q340. The B electrode of the transistor Q340 is connected to one end of the capacitor C342, resistors R345 and R346 respectively. The other end of the capacitor C342 is connected to the E electrode of the transistor Q340 and then grounded. The other end of the resistor R346 is connected to the E electrode of the transistor Q340 and then grounded. The other end of the resistor R345 is connected to the I / O port of the MCU. By connecting a ceramic capacitor C342 in parallel between the B electrode of the control transistor Q340 and the E electrode of the transistor Q340, the high-voltage and high-frequency EFT pulses generated in the driving circuit can be absorbed and processed to ensure that the thyristor and the control device will not be broken down by high voltage or micro-conduction will occur.
[0015] The anti-interference thyristor drive circuit has a simple structure. It absorbs high-voltage and high-frequency EFT pulses through a clever circuit loop, protects the thyristor and control devices from being broken down by EFT, avoids micro-conduction, greatly improves the reliability of the circuit, prevents abnormal rotation or heating of the motor, avoids burning of the entire machine, and increases the service life and reliability of the product. It can effectively pass the 5KV EFT test and improve the reliability of the drive circuit.
[0016] In this embodiment, the loop formed by capacitor C340, resistor R340, and R341 in series is not limited to the surface mount or direct insertion mode of the device, nor is it limited to slight changes in the size of parameters, nor is it limited to the resistance, capacitor, single or multiple resistors in parallel or series; capacitor C341 is not limited to a single or multiple capacitors in parallel or series, is not limited to surface mount or direct insertion mode, or a single or multiple resistors in series; driving resistors R342 and R343 are not limited to multiple resistors in series or parallel; capacitor C342 is not limited to a single or multiple capacitors in series or parallel, and is not limited to whether a single or multiple resistors are connected in series.
[0017] The above is only a preferred embodiment of the present invention, but the present invention should not be limited to the contents disclosed in the embodiment and the drawings, so any equivalent or modification completed without departing from the spirit disclosed in the present invention shall fall within the scope of protection of the present invention.
Claims
1. An anti-interference thyristor drive circuit, characterized in that include: Capacitors C341, C342; driving resistor; Resistors R345 and R346; transistor Q340; thyristor T340 and load HEAT, wherein the T1 pole of the thyristor T340 is respectively connected to the capacitor C341 and the ACL-AC of the power supply, the other end of the capacitor C341 is connected to the E pole of the transistor Q340 and then to ground, the T2 pole of the thyristor T340 is connected to one end of the load HEAT, the other end of the load HEAT is connected to the ACN of the power supply, the control pole G pole of the thyristor T340 is connected to one end of the driving resistor, the other end of the driving resistor is connected to the C pole of the transistor Q340, the B pole of the transistor Q340 is respectively connected to one end of the capacitor C342, the resistor R345 and R346, the other end of the capacitor C342 is connected to the E pole of the transistor Q340 and then to ground, the other end of the resistor R346 is connected to the E pole of the transistor Q340 and then to ground, and the other end of the resistor R345 is connected to the I / O port of the MCU.
2. The anti-interference thyristor drive circuit according to claim 1, characterized in that: It also includes a capacitor C340, resistors R340 and R341, wherein one end of the capacitor C340 is connected to a line connecting the capacitor C341 and the power supply ACL-AC, the other end of the capacitor C340 is connected to the resistor R340, the other end of the resistor R340 is connected to the resistor R341, and the other end of the resistor R341 is connected to a line connecting the T2 pole of the thyristor T340 and the load HEAT.
3. The anti-interference thyristor drive circuit according to claim 1, characterized in that: The driving resistor is formed by connecting resistors R342 and R343 in parallel.