IONIC THERMAL DISSIPATION DEVICE

Abstract

An ionic thermal dissipation device includes an ionic wind generating system and a power system to drive the ionic wind generating system. The power system first converts external direct current power signals into alternating current (AC) power signals, and boosts the AC power signals. The power system doubles voltage of the boosted AC power signals, and rectifies the boosted AC power signals to generate high voltage direct current power signals to drive the ionic wind generating system. The power system also detects current signals generated by ion excitation of the ionic wind generating system, and regulates the high voltage direct current power signals according to the detected current signals.

Description

BACKGROUND

1. Technical Field

The disclosure relates to thermal dissipation devices, and particularly to an ionic thermal dissipation device.

2. Description of Related Art

Ionic thermal dissipation devices usually utilize voltage feedback. Thus, the ionic thermal dissipation devices regulate ionic excitation voltage according to feedback voltage to control velocity of generated ionic wind. However, temperature may influence the ionic excitation voltage, that is, the ionic thermal dissipation devices with same ionic excitation voltage may have different velocities of ionic wind in different temperature environments. Thus, the voltage feedback cannot effectively control the velocity of ionic wind of the ionic dissipation devices. In addition, utilizing the voltage feedback, the ionic excitation voltages of the ionic thermal dissipation devices are set at predetermined values, such as, 5000˜6000V, according to needed velocities of ionic wind, which results in arcing when the temperature changes.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram of one embodiment of an ionic thermal dissipation device as disclosed.

FIG. 2 is a schematic diagram of another embodiment of an ionic thermal dissipation device as disclosed.

FIG. 3 is a circuit diagram of one embodiment of a current feedback circuit of an ionic thermal dissipation device.

DETAILED DESCRIPTION

FIG. 1 is a schematic diagram of one embodiment of an ionic thermal dissipation device 10 as disclosed. The ionic thermal dissipation device 10 includes a power system 100 and an ionic wind generating system 200. The power system 100 converts external direct current (DC) power signals Vin into high voltage DC power signals Vout, where the high voltage DC power signals Vout drive the ionic wind generating system 200 to generate ionic wind to dissipate heat. In one embodiment, the power system 100 includes a power stage circuit 110, a pulse width modulation (PWM) controller 120, a transformer 130, a voltage double and rectifier circuit 140, and a current feedback circuit 150. The ionic wind generating system 200 includes an emitting pole 210 and a receiving pole 220.

In one embodiment, the power stage circuit 110 includes DC to alternating current (AC) converter circuit to convert the external DC power signals Vin into AC power signals. In alternative embodiments, the power stage circuit 110 further includes a DC/DC converter circuit to regulate voltage level of the external DC power signals Vin. The PWM controller 120 controls the power stage circuit 110 to regulate voltage and frequency of the AC power signals output by the power stage circuit 110. The transformer 130 may be a boost transformer to boost the AC power signals. The voltage double and rectifier circuit 140 doubles voltage of the boosted AC power signals and rectifies the boosted AC power signals to generate the high voltage DC power signals Vout to drive the ionic wind generating system 200.

The emitting pole 210 of the ionic wind generating system 200 receives the high voltage DC power signals Vout, and excites air ionization to generate positive ions or negative ions. The positive ions or the negative ions move from the emitting pole 210 to the receiving pole 220, causing the air to generate the ionic wind. At the same time, the movement of the positive ions or the negative ions between the emitting pole 210 and the receiving pole 220 form minor currents, such as, 0.1 to 0.5 mA, that is, current signals generated by ion excitation. If a distance between the emitting pole 210 and the receiving pole 220 is fixed, the current signals are proportionate to ion concentration of the ionic wind generating system 200. That is, the current signals are proportionate to velocity of the ionic wind. For example, when the distance between the emitting pole 210 and receiving pole 220 is 7 mm, if the current signal generated by the ion excitation is changed from 0.1 mA to 0.5 mA, the velocity of the ionic wind needs to be changed from 1.4 m/s to 2.0 m/s. In addition, when the ionic thermal dissipation device 10 arcs, the current signal becomes apparently high due to discharge between the emitting pole 210 and the receiving pole 220.

The current feedback circuit 150 detects the current signals generated by the ion excitation of the ionic wind generating system 10, and feedbacks the detected current signals to the PWM controller 120. Thus, the PWM controller 120 regulates the voltage and the frequency of the AC power signals output by the power stage circuit 110 to control the voltage of the high voltage DC power signals Vout output by the power system 100. Because environmental temperatures have no influence on the current signals generated by the ion excitation, thus, current feedback can effectively regulate velocity of the ionic wind of the ionic wind generating system 200. In addition, when the current signals exceed a predetermined value, for example 1A, the PWM controller 120 determines the ionic thermal dissipation device 10 arcs, and turns off the power stage circuit 110 to implement arcing protection.

As shown in FIG. 1, the current feedback circuit 150 is connected to a low voltage end of a secondary winding of the transformer 130 and the PWM controller 120. The current feedback circuit 150 detects the current signals from the low voltage end of the secondary winding of the transformer 130, and feedbacks the detected current signals to the PWM controller 120. As shown in FIG. 3, the current feedback circuit 150 includes a diode D1, a resistor R1, and a capacitor C1. The diode D1 detects and rectifies the current signals, and has an anode connected to the low voltage end of the secondary winding of the transformer 130 and a cathode connected to the PWM controller 120. The capacitor C1 is connected between the cathode of the diode D1 and the ground, and suppresses noises of the current signals. The resistor R1 is connected between the cathode of the diode D1 and the ground, and forms voltage signals according to the current signals to control the PWM controller 120.

FIG. 2 is a schematic diagram of another embodiment of an ionic thermal dissipation device 10′ as disclosed. In this embodiment, the current feedback circuit 150 is connected to the receiving pole 220 of the ionic wind generating circuit 200 and the PWM controller 120, and other structures and connections of the ionic thermal dissipation device 10′ are similar to those of the ionic thermal dissipation device 10 of FIG. 1. Therefore, descriptions are omitted here. The current feedback circuit 150 detects the current signals from the receiving pole 220 of the ionic wind generating system 200, and feedbacks the detected current signals to the PWM controller 120. Accordingly, the anode of the diode D1 of the current feedback circuit 150 is connected to the receiving pole 220 of the ionic wind generating system 200, and the cathode of the diode D1 is connected to the PWM controller 120.

The ionic thermal dissipation devices 10 and 10′ utilize current feedback, which avoids influence of environmental temperatures, and effectively control velocity of the ionic wind of the ionic thermal dissipation devices 10 and 10′ and implement arcing protection.

The foregoing disclosure of various embodiments has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise forms disclosed. Many variations and modifications of the embodiments described herein will be apparent to one of ordinary skill in the art in light of the above disclosure. The scope of the invention is to be defined only by the claims appended hereto and their equivalents.

Claims

1. An ionic thermal dissipation device, comprising: an ionic wind generating system; anda power system, the power system comprising: a power stage circuit, operable to converting external direct current power signals into alternating current (AC) power signals;a transformer, operable to boost the AC power signals;a voltage double and rectifier circuit, operable to double voltage of the boosted AC power signals and rectify the boosted AC power signals to generate high voltage direct current power signals suitable to drive the ionic wind generating system;a current feedback circuit, operable to detect current signals generated by ion excitation of the ionic wind generating system; anda pulse width modulation (PWM) controller, operable to control the power stage circuit to regulate the high voltage direct current power signals according to the detected current signals.

2. The ionic thermal dissipation device of claim 1, wherein the current feedback circuit is connected to a low voltage end of a secondary winding of the transformer and the PWM controller, and detects the current signals from the low voltage end of the secondary winding of the transformer and feedbacks the detected current signals to the PWM controller.

3. The ionic thermal dissipation device of claim 2, wherein the current feedback circuit comprises: a diode, comprising an anode connected to the low voltage end of the secondary winding of the transformer and a cathode connected to the PWM controller;a resistor, connected between the cathode of the diode and the ground; anda capacitor, connected between the cathode of the diode and the ground.

4. The ionic thermal dissipation device of claim 1, wherein the ionic wind generating system comprises: an emitting pole, operable to receive the high voltage direct current power signals to excite ions; andan receiving pole, operable to receive the ions excited by the emitting pole.

5. The ionic thermal dissipation device of claim 4, wherein the current feedback circuit is connected to the receiving pole of the ionic wind generating system and the PWM controller, and detects the current signals from the receiving pole of ionic wind generating system and feedbacks the detected current signals to the PWM controller.

6. The ionic thermal dissipation device of claim 5, wherein the current feedback circuit comprises: a diode, comprising an anode connected to the receiving pole of the ionic wind generating system and a cathode connected to the PWM controller;a resistor, connected between the cathode of the diode and the ground; anda capacitor, connected between the cathode of the diode and the ground.