A cabinet dual cooling fan energy-saving control device

Abstract

The invention discloses a cabinet dual cooling fan energy-saving control device, comprising: a power switch, a rectifier bridge, a unidirectional thyristor, a thermistor, a charging capacitor, a first resistor to a fourth resistor, a second cooling fan and a temperature control switch; the input end of the rectifier bridge is connected in series with the first cooling fan and then connected to an AC 220V power supply through a power switch; the first resistor and the second resistor are connected in series and connected to the positive and negative output ends of the rectifier bridge; the charging capacitor is connected in parallel at both ends of the second resistor; the thermistor is connected in series with the fourth resistor and the third resistor and then connected in parallel at both ends of the charging capacitor; the anode of the unidirectional thyristor is connected to the positive electrode of the rectifier bridge, the cathode is connected to the negative electrode of the rectifier bridge, and the control electrode is connected between the fourth resistor and the thermistor; the temperature control switch and the second cooling fan are connected in series and also connected to an AC 220V power supply through a power switch. The cabinet dual cooling fan energy-saving control device provided by the invention realizes automatic start and stop and speed regulation of the fan according to the temperature change of the cabinet, which is more energy-saving.

Description

Technical Field

[0001] The invention relates to the technical field of electrical engineering, and more particularly to an energy-saving control device for dual cooling fans of a cabinet. Background Art

[0002] With the widespread application of high-power inverters in the fields of industry and agriculture, especially in the fields of 24-hour operation such as oil field production, outdoor skid-type water injection pump room, variable frequency oil transportation, etc., there are a large number of electrical cabinets in the field to protect the inverter and other electrical control equipment from the erosion of wind, sand, rain and snow. Since these electrical control equipment has a large power capacity and generates a lot of heat when working, two fans are generally required for heat dissipation. However, as long as the control cabinet is powered on, these two fans will keep running at full speed day and night regardless of spring, summer, autumn and winter. In reality, it is neither timely nor realistic to arrange manual switching. Therefore, a large amount of electricity is wasted, the life of the fan is affected, and the operation and maintenance costs are increased.

[0003] Therefore, how to provide a more energy-saving cooling fan control device is a problem that those skilled in the art need to solve urgently. Summary of the invention

[0004] In view of this, the present invention provides an energy-saving control device for dual cooling fans of a cabinet, which realizes that the cooling fans are started only when the cabinet temperature rises and heat is needed, thereby achieving the purpose of energy saving and consumption reduction and automatic heat dissipation.

[0005] In order to achieve the above object, the present invention adopts the following technical solution:

[0006] A cabinet dual cooling fan energy-saving control device, comprising: a power switch, a rectifier bridge, a unidirectional thyristor, a thermistor, a charging capacitor C1, a first resistor R1, a second resistor R2, a third resistor R3, a fourth resistor R4, a second cooling fan and a temperature control switch;

[0007] The input end of the rectifier bridge is connected in series with the first cooling fan and then connected to an AC 220V power supply through a power switch;

[0008] The first resistor R1 and the second resistor R2 are connected in series and connected to the positive and negative output ends of the rectifier bridge;

[0009] The charging capacitor C1 is connected in parallel across the second resistor R2;

[0010] The thermistor is connected in series with the fourth resistor R4 and the third resistor R3 and then connected in parallel at both ends of the charging capacitor C1;

[0011] The anode of the unidirectional thyristor is connected to the positive electrode of the rectifier bridge, the cathode is connected to the negative electrode of the rectifier bridge, and the control electrode is connected between the fourth resistor R4 and the thermistor;

[0012] The temperature control switch and the second cooling fan are connected in series and are also connected to an AC 220V power supply through a power switch.

[0013] Preferably, the thermistor is an NTC thermistor.

[0014] Preferably, the temperature control switch is a normally closed temperature control switch.

[0015] Preferably, the fourth resistor R4 is a potentiometer.

[0016] Through the above technical solution, it can be known that compared with the prior art, the present invention discloses a cabinet dual cooling fan energy-saving control device. When the cabinet temperature is low, the first and second cooling fans automatically stop. When the temperature reaches the required fanning temperature, the first cooling fan starts to dissipate heat and speeds up the heat dissipation as the temperature rises. Moreover, when the first cooling fan has insufficient heat dissipation capacity, the second cooling fan starts to dissipate heat; conversely, as the cabinet temperature decreases, the second cooling fan and the first cooling fan are shut down, slowed down, and stop dissipating heat in turn.

[0017] The cabinet dual cooling fan energy-saving control device provided by the present invention does not require manual intervention in the entire cooling process, realizes automatic cooling control all year round, and automatically realizes the cooling fan not working at low temperature, the single fan speed-adjusting work at normal temperature, and the dual fans working at the same time at high temperature. It is not only suitable for dual-fan occasions, but also for single-fan occasions, which not only saves energy, but also extends the service life of the fan and reduces maintenance costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0019] Figure 1 This is a structural schematic diagram of the cabinet dual cooling fan energy-saving control device provided by the present invention. DETAILED DESCRIPTION

[0020] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0021] See attached Figure 1, the embodiment of the present invention discloses a cabinet dual cooling fan energy-saving control device, including: a power switch, a rectifier bridge, a unidirectional thyristor, a thermistor, a charging capacitor C1, a first resistor R1, a second resistor R2, a third resistor R3, a fourth resistor R4, a second cooling fan and a temperature control switch;

[0022] The input end of the rectifier bridge is connected in series with the first cooling fan and then connected to an AC 220V power supply through a power switch SW;

[0023] The first resistor R1 and the second resistor R2 are connected in series and connected to the positive and negative electrodes of the rectifier bridge;

[0024] The charging capacitor C1 is connected in parallel across the second resistor R2;

[0025] The thermistor is connected in series with the fourth resistor R4 and the third resistor R3 and then connected in parallel across the charging capacitor C1;

[0026] The anode of the unidirectional thyristor is connected to the positive electrode of the rectifier bridge, the cathode is connected to the negative electrode of the rectifier bridge, and the control electrode is connected between the fourth resistor R4 and the thermistor; preferably, the thermistor adopts an NTC thermistor.

[0027] After the temperature control switch is connected in series with the second cooling fan, it is also connected to the AC 220V power supply through the power switch. The branch of the temperature control switch and the second cooling fan in series is connected in parallel to the two ends of the branch of the rectifier bridge and the first cooling fan in series. The fan start and stop are directly controlled by the temperature control switch ST. For example, if a 40°C dynamic closing temperature control switch is selected, when the temperature inside the chassis reaches the operating temperature, the temperature control switch is closed, and the auxiliary fan assists in heat dissipation at full speed.

[0028] The working principle of the technical solution provided by the present invention is as follows: 220V AC is rectified into pulsating DC by a rectifier bridge B, and the pulsating DC is charged to a charging capacitor C1 through a first resistor R1 after the voltage passes through zero. The voltage limit value that can be charged in one pulse cycle is not only affected by the first resistor R1 and the charging time constant of the charging capacitor C1, but also limited by the voltage divided by the second resistor R2 and the first resistor R1; the voltage on the charging capacitor C1 is divided again by an NTC thermistor RT1 and a third resistor R3 and a fourth resistor R4, and then added to the control stage of a unidirectional thyristor SCR, and the voltage is adjusted by the first resistor R1, the second resistor R2, the charging capacitor C1, the NTC thermistor RT1, the third resistor R3 and other components. The number selection and the fine adjustment of the fourth resistor R4 ensure that the control level voltage applied to the unidirectional thyristor SCR is lower than its conduction voltage even at the peak of the pulse voltage when the cabinet temperature is not high (for example, below 20°C), so the unidirectional thyristor does not conduct and the main fan (the first cooling fan) does not work; when the cabinet temperature rises (for example, above 30°C), the resistance of the NTC thermistor decreases, and the voltage division ratio on the third resistor R3 and the fourth resistor R4 increases. Therefore, at a certain moment when the voltage of the charging capacitor C1 rises, the voltage division on the third resistor R3 exceeds the conduction voltage of the unidirectional thyristor SCR, the unidirectional thyristor SCR conducts, and the main fan (the first cooling fan) starts to run at a low speed. If the temperature continues to rise, the resistance of the NTC thermistor becomes smaller, the unidirectional thyristor SCR conducts earlier, the conduction angle increases, and the main fan speed increases.

[0029] The two cooling fans do not work at low temperatures. When the temperature required for fanning is reached, the first cooling fan automatically turns on. When the capacity of the first cooling fan is insufficient, the second cooling fan starts to achieve auxiliary heat dissipation. The technical solution provided by the present invention is not only suitable for dual-fan occasions, but also suitable for single-fan occasions, which saves energy, prolongs the service life of the fan, and reduces maintenance costs.

[0030] Preferably, the cabinet dual cooling fan energy-saving control device should be made of metal or partially metal casing, and the temperature control switch ST can be installed close to the metal part. The NTC thermistor should be led out through an insulated lead wire and properly fixed in a place that can reflect the actual temperature of the cabinet, such as above the cooling vent of the frequency converter cabinet.

[0031] Components are preferred but not limited to: rectifier bridge B is KBP206; unidirectional thyristor is BT169; R1 is 300K / 0.5W; R2 is 10K / 0.25W; R3 is 510Ω / 0.25W; R4 is 1KΩ precision potentiometer; thermistor is R 25 =10K negative temperature system, for example: MF52B103F4100A; capacitor C1 selects 223, 50V; ST selects KSD301 normally open, 40℃; the power switch selects an ordinary 220V / 10A power switch.

[0032] It should be noted that this embodiment is only one of the preferred embodiments, and the purpose is to explain the technical solution of the present invention in detail. Obviously, with the technical solution of the present invention, different power supply voltages have some influence on the starting temperature of the main fan. Those skilled in the art can properly adjust the parameters of the components according to the different temperature requirements of the cabinet. The potentiometer in the technical solution provided by the present invention is not necessary, and is mainly to meet the different starting heat dissipation temperature requirements of different users. In practice, R4 can be adjusted at a certain appropriate temperature, and finally R3 and R4 are combined into a fixed resistor.

[0033] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part.

[0034] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A cabinet dual cooling fan energy-saving control device, characterized in that: include: A power switch, a rectifier bridge, a thyristor, a thermistor, a charging capacitor C1, a first resistor R1, a second resistor R2, a third resistor R3, a fourth resistor R4, a second cooling fan and a temperature control switch; The input end of the rectifier bridge is connected in series with the first cooling fan and then connected to an AC 220V power supply through a power switch; The first resistor R1 and the second resistor R2 are connected in series and connected to the positive and negative output ends of the rectifier bridge; The charging capacitor C1 is connected in parallel across the second resistor R2; The thermistor is connected in series with the fourth resistor R4 and the third resistor R3 and then connected in parallel at both ends of the charging capacitor C1; The anode of the unidirectional thyristor is connected to the positive electrode of the rectifier bridge, the cathode is connected to the negative electrode of the rectifier bridge, and the control electrode is connected between the fourth resistor R4 and the thermistor; The temperature control switch and the second cooling fan are connected in series and are also connected to an AC 220V power supply through a power switch.

2. The energy-saving control device for dual cooling fans of a cabinet according to claim 1, characterized in that: The thermistor includes: an NTC thermistor.

3. The energy-saving control device for dual cooling fans of a cabinet according to claim 2, characterized in that: The temperature control switch comprises: a normally closed temperature control switch.

4. A cabinet dual cooling fan energy-saving control device according to any one of claims 1 to 3, characterized in that: The fourth resistor R4 includes a potentiometer.

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