Method, apparatus, and system for providing a voltage supply to a photoionization detector lamp

Abstract

Methods, apparatus, and systems are provided for providing an alternating current (AC) voltage supply to a photoionization detector lamp from a direct current (DC) voltage source. Example apparatus may include a DC voltage to DC voltage (DC / DC) converter circuit; and a feedback circuit that is electronically coupled to the DC / DC converter circuit and converts a reference AC voltage into a feedback DC voltage for the DC / DC converter circuit. In some examples, the feedback circuit may be electronically coupled to a DC voltage to AC voltage (DC / AC) conversion circuit to obtain the reference AC voltage.

Description

Technical Field

[0001] The present disclosure generally relates to methods, apparatus, and systems for providing a voltage supply, and more particularly to methods, apparatus, and systems for providing an alternating current (AC) voltage supply for a photoionization detector (PID) lamp. Background Art

[0002] A gas detector is a device that can detect and / or measure the concentration level of compounds in a gaseous substance, the compounds including, for example, organic compounds and inorganic compounds. For example, a photoionization detector (PID) is a gas detector that can measure the concentration level of volatile organic compounds in a gaseous substance. The term "volatile organic compound" (or "VOC") refers to an organic compound that can have a high vapor pressure at normal room temperature (i.e., they can easily turn into a gas or vapor). Example chemical substances in example volatile organic compounds can include, for example, formaldehyde, methane, and benzene.

[0003] A high level concentration of volatile organic compounds in indoor air or outdoor air can cause adverse effects on health and the environment. Thus, photoionization detectors can be used to measure and monitor the concentration level of volatile organic compounds at various indoor and / or outdoor locations.

[0004] A photoionization detector can be installed within a portable device that can be powered by a low direct current (DC) power source such as, for example, a battery. However, many photoionization detectors may require a supply of high alternating current (AC) power as a drive voltage for various components of the photoionization detector. In this regard, existing methods and devices have failed to overcome the technical challenges associated with converting low DC power into high AC power for a photoionization detector. Summary of the Invention

[0005] Various embodiments described herein relate to methods, apparatus, and systems for providing a voltage supply for a photoionization detector (PID) lamp. In particular, various embodiments relate to converting a low direct current (DC) voltage into a high alternating current (AC) voltage supply for powering a photoionization detector lamp.

[0006] According to various embodiments of the present disclosure, there is provided an apparatus for providing a voltage supply for a photoionization detector lamp. The apparatus includes a DC voltage to DC voltage (DC / DC) converter circuit, and a feedback circuit that is electronically coupled to the DC / DC converter circuit and a DC voltage to AC voltage (DC / AC) conversion circuit.

[0007] In some examples, the DC / DC converter circuit may include a DC / DC converter, and the DC / DC converter may be electronically coupled to a direct current (DC) voltage source and convert an input DC voltage from the DC voltage source into a compensated DC voltage at least partially based on a feedback DC voltage.

[0008] In some examples, the DC / AC conversion circuit may be electronically coupled to both the DC / DC converter circuit and the photoionization detector lamp, and may convert the compensated DC voltage into an AC voltage supply for the photoionization detector lamp.

[0009] In some examples, the DC / AC conversion circuit may include an oscillation circuit and a transformer circuit electronically coupled to each other. In some examples, the oscillation circuit may be electronically coupled to the DC / DC converter. In some examples, the transformer circuit may be electronically coupled to the photoionization detector lamp.

[0010] In some examples, the transformer circuit of the DC / AC conversion circuit may include a primary winding and a secondary winding. In some examples, the secondary winding may include a transformer tap, and the reference voltage conversion circuit may be electronically coupled to the transformer tap. In some examples, the transformer tap is positioned between 5% (inclusive) and 20% (inclusive) of the secondary winding of the transformer circuit. In some examples, the transformer tap is positioned at 6% of the secondary winding of the transformer circuit.

[0011] In some examples, the feedback circuit may be electronically coupled to both the DC / DC converter circuit and the DC / AC conversion circuit. In some examples, the feedback circuit may obtain a reference AC voltage associated with the AC voltage supply, and may convert the reference AC voltage into a feedback DC voltage for the DC / DC converter.

[0012] In some examples, the feedback circuit may include a reference voltage conversion circuit and a reference voltage division circuit electronically coupled to each other.

[0013] In some examples, the reference voltage conversion circuit may be electronically coupled to the transformer circuit. In some examples, the reference voltage conversion circuit may convert the reference AC voltage into a reference DC voltage. In some examples, the reference voltage conversion circuit may include a diode element and a capacitor element electronically coupled to each other. In some examples, the diode element may be electronically coupled to the transformer circuit. In some examples, the capacitor element may have a capacitance between 1 nano-farad (inclusive) and 100 nano-farads (inclusive).

[0014] In some examples, a reference voltage dividing circuit may be electronically coupled to a DC / DC converter. In some examples, the reference voltage dividing circuit may convert a reference DC voltage into a feedback DC voltage and provide the feedback DC voltage to the DC / DC converter. In some examples, the reference voltage dividing circuit may include two resistor elements that are electronically coupled to each other. In some examples, each of the two resistor elements may have a resistance between 100 kiloohms (inclusive) and 10 megohms (inclusive).

[0015] In some examples, the feedback circuit may include an amplifier element that is electronically coupled to the DC / DC converter. In some examples, the feedback circuit may include a microcontroller unit that is electrically coupled to the DC / DC converter. In some examples, the system may include a switching circuit that is electronically coupled to the DC / DC converter.

[0016] According to various embodiments of the present disclosure, a system is provided for providing an AC voltage supply to a photoionization detector lamp from a DC voltage source having an input DC voltage. The system may include, for example, (1) a DC voltage to DC voltage (DC / DC) converter circuit, (2) a DC voltage to AC voltage (DC / AC) conversion circuit, and (3) a feedback circuit.

[0017] According to various embodiments of the present disclosure, a method for providing an alternating current (AC) voltage supply to a photoionization detector lamp from a direct current (DC) voltage source having an input DC voltage. The method includes obtaining a reference AC voltage associated with a DC voltage to AC voltage (DC / AC) conversion circuit electronically coupled to the photoionization detector lamp, converting the reference AC voltage into a feedback DC voltage, converting the input DC voltage into a compensated DC voltage at least in part based on the feedback DC voltage, and causing the compensated DC voltage to be supplied to the DC / AC conversion circuit.

[0018] The foregoing illustrative summary and other exemplary objects and / or advantages of the present disclosure and the manner in which they are achieved are further explained in the following detailed description and its accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The description of the illustrative embodiments may be understood in conjunction with the accompanying drawings. It will be appreciated that, for simplicity and clarity of illustration, the elements illustrated in the figures are not necessarily drawn to scale unless otherwise described. For example, the dimensions of some elements may be exaggerated relative to other elements unless otherwise described. Embodiments incorporating the teachings of the present disclosure are illustrated and described herein with reference to the various figures, wherein:

[0020] Figure 1Illustrated is an exemplary schematic diagram showing an example photoionization detector lamp according to various embodiments of the present disclosure;

[0021] Figure 2 Illustrated is an exemplary block diagram of an example system according to various embodiments of the present disclosure;

[0022] Figure 3 Illustrated is an exemplary circuit diagram according to various embodiments of the present disclosure;

[0023] Figure 4 Illustrated is an exemplary circuit diagram according to various embodiments of the present disclosure;

[0024] Figure 5 Illustrated is an exemplary circuit diagram according to various embodiments of the present disclosure;

[0025] Figure 6 Illustrated is an exemplary alternating current (AC) waveform diagram according to various embodiments of the present disclosure;

[0026] Figure 7 Illustrated is an exemplary AC waveform diagram according to various embodiments of the present disclosure;

[0027] Figure 8 Illustrated is an exemplary AC waveform diagram according to various embodiments of the present disclosure;

[0028] Figure 9 Illustrated is an exemplary AC waveform diagram according to various embodiments of the present disclosure; and

[0029] Figure 10 Illustrated is an exemplary flowchart of an example method according to various embodiments of the present disclosure. Detailed Description

[0030] Some embodiments of the present disclosure will now be described more fully hereinafter with reference to the accompanying drawings, in which some, but not all, embodiments of the present disclosure are shown. In fact, these disclosures may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will satisfy applicable legal requirements. Like reference numerals refer to like elements throughout.

[0031] The phrases "in one embodiment," "according to an embodiment," and the like generally mean that the particular feature, structure, or characteristic following the phrase may be included in at least one embodiment of the present disclosure and may be included in more than one embodiment of the present disclosure (importantly, such phrases do not necessarily refer to the same embodiment).

[0032] The terms "example" or "exemplary" are used herein to mean "serving as an example, instance, or illustration". Any implementation described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other implementations.

[0033] If the specification states that a component or feature "can", "is able to", "may", "should", "will", "preferably", "might", "typically", "optionally", "for example", "generally", or "possibly" (or other such language) be included or have a characteristic, it is not required that the particular component or feature be included or have the characteristic. Such a component or feature may optionally be included in some embodiments, or it may be excluded.

[0034] The term "electronically coupled" in the present disclosure means that two or more electrical components (such as but not limited to (multiple) resistor elements, (multiple) capacitor elements, (multiple) inductor elements, (multiple) diode elements) and / or (multiple) circuits are connected by wired means (such as but not limited to conductive wires or traces) and / or wireless means (such as but not limited to electromagnetic fields) such that energy (such as but not limited to current), data, and / or information can be transmitted to and / or received from the electronically coupled electrical components and / or (multiple) circuits.

[0035] As described above, there are technical challenges in converting a direct current (DC) voltage to an alternating current (AC) voltage for use in a photoionization detector lamp. For example, a low DC voltage (such as but not limited to 3.3 volts) may be supplied to the photoionization detector, while the photoionization detector lamp of the photoionization detector may require a high AC voltage (such as but not limited to 1200 volts peak-to-peak) to operate properly. In some examples, the photoionization detector may include a direct current to alternating current (DC / AC) converter circuit to perform the required conversion.

[0036] In some examples, the DC / AC converter circuit may include an oscillator circuit and a transformer circuit. In such examples, the oscillator circuit may convert the input DC voltage to an AC voltage, and the transformer circuit may convert the AC voltage from the oscillator circuit to a higher AC voltage for powering the photoionization detector lamp.

[0037] However, the accuracy of these conversions can be affected by various such factors. For example, temperature can affect the electrical properties (such as conductivity, resistance) of various components (such as resistors, capacitors, transformers, etc.) in a DC / AC converter circuit. In addition, the actual electrical properties of these components can fluctuate within a percentage error from the labeled electrical properties of these components. These factors, when compounded with the characteristics of these conversions (such as high input current, high output frequency, high conversion rate), can cause the DC / AC converter circuit to output an incorrect AC drive voltage to the photoionization detector lamp. In other words, the actual output AC voltage from the DC / AC converter circuit can drift from the calculated, desired output voltage for the photoionization detector lamp. This voltage drift can cause turn-on failures and reading errors of the photoionization detector lamp and, in addition, can result in incorrect measurements through the photoionization detector.

[0038] In this regard, various example embodiments of the present disclosure can overcome these technical challenges associated with converting a direct current (DC) voltage to an alternating current (AC) voltage for a photoionization detector lamp based on the following example embodiments: The example embodiments include a DC voltage to DC voltage (DC / DC) converter circuit, a DC voltage to AC voltage (DC / AC) conversion circuit, and / or a feedback circuit. In particular, some example embodiments of the present disclosure can reduce the risk of photoionization detector lamp turn-on failures and reading errors and can compensate for factors that can affect voltage conversion as described above. In addition, some example embodiments of the present disclosure can eliminate the need for separate power sources for the photoionization detector and the photoionization detector lamp, thereby providing increased utilization and improved cost efficiency.

[0039] Now referring to Figure 1 , there is provided an example schematic diagram showing an example photoionization detector lamp 100 in accordance with various embodiments of the present disclosure. In particular, the example photoionization detector lamp 100 can include a glass tube member 101 and a window member 103.

[0040] In some examples, the glass tube member 101 can include a gaseous substance or a combination of gaseous substances, which can include, for example but not limited to, an inert gas, such as argon (Ar), xenon (Xe), and / or krypton (Kr). The (multiple) gaseous substances within the glass tube member 101 can be excited by any of various excitation methods to produce an ultraviolet (UV) light source.

[0041] For example, a voltage (such as an alternating current (AC) voltage) can be applied via, for example Figure 1is supplied to the glass tube member 101 by a pair of electrodes 115A and 115B as shown. In such an example, an AC voltage can cause ionization of the gaseous substance(s) within the glass tube member 101, resulting in a glow discharge. In particular, ions can alternately travel towards each of the electrodes 115A and 115B, thereby generating a current and forming a plasma. The glow discharge associated with the plasma can emit low-wavelength ultraviolet (UV) light.

[0042] Referring back to Figure 1 , the ultraviolet light can be transmitted through the window member 103. In some examples, the window member 103 can include material(s) that enable and / or facilitate the transmission of low-wavelength ultraviolet light, such materials including, for example, salt crystal materials. When the ultraviolet light passes through the window member 103, the molecules in the gaseous substance that the photoionization detector is configured to detect can be exposed to the ultraviolet light.

[0043] As described above, the photoionization detector can be configured to detect, for example, volatile organic compounds (VOCs) in air. In this regard, an anode element and a cathode element are provided. In some examples, the anode element can be an electrode that attracts negatively charged electrons. In some examples, the cathode element can be an electrode that attracts positively charged electrons.

[0044] As Figure 1 shown, air can flow through the photoionization detector in the direction indicated by arrow 105. The air can include VOC molecules 109 and non-VOC molecules 107. When the VOC molecules 109 and non-VOC molecules 107 pass through the photoionization detector, they can be exposed to the ultraviolet light generated by the photoionization detector lamp 100.

[0045] In particular, as Figure 1 shown, the ultraviolet light can cause photoionization of the VOC molecules 109, which can result in the ejection of electrons from the VOC molecules 109 and the formation of positively charged ions. The electrons can travel to the anode element, while the positively charged ions can travel to the cathode element. When the electrons and the positively charged ions are pushed to the corresponding electrodes, a current can be generated.

[0046] In contrast, the ultraviolet light does not cause photoionization of the non-VOC molecules 107, and the non-VOC molecules 107 do not generate a current. In other words, the current generated by ultraviolet photoionization is proportional to the amount of VOC molecules 109 in the air. Thus, the concentration level of volatile organic compounds (VOCs) can be determined by the photoionization detector at least in part based on the current.

[0047] As described above, a photoionization detector depends at least in part on photoionization of molecules caused by ultraviolet light generated by a photoionization detector lamp. Thus, providing an appropriate voltage supply to the photoionization detector lamp may be important for photoionization detector performance. However, many factors can affect the voltage supply to the photoionization detector lamp, resulting in an actual output AC voltage that drifts from the calculated, desired output voltage, as described above.

[0048] In this regard, various embodiments of the present disclosure can be embodied as systems and apparatuses for providing an alternating current (AC) voltage supply to a photoionization detector (PID) lamp. Now referring Figure 2 to, an example block diagram of various components of an example system and apparatus in accordance with various embodiments of the present disclosure is shown.

[0049] As Figure 2 shown, example system 200 can include a DC voltage to DC voltage (DC / DC) converter circuit 206, a DC voltage to AC voltage (DC / AC) conversion circuit 208, and a feedback circuit 210. The DC / DC converter circuit 206 can be electronically coupled to the DC / AC conversion circuit 208. The feedback circuit 210 can be electronically coupled to both the DC / DC converter circuit 206 and the DC / AC conversion circuit 208.

[0050] In some examples, the DC / DC converter circuit 206 can include a DC / DC converter 212. The DC / DC converter 212 can be configured to convert one DC voltage to another. For example, the DC / DC converter 212 can be electronically coupled to a direct current (DC) voltage source 202. The DC voltage source 202 can provide an input DC voltage (e.g., but not limited to 3.3 volts), and the DC / DC converter 212 can convert the input DC voltage to a compensated DC voltage based at least in part on a feedback DC voltage provided by the feedback circuit 210. Further illustration and description of an example structure of the DC / DC converter circuit 206 is provided below in connection with at least Figure 3 , Figure 4 and Figure 5 .

[0051] In some examples, the DC / DC converter 212 can be electronically coupled to the DC / AC conversion circuit 208 and provide the compensated DC voltage to the DC / AC conversion circuit 208.

[0052] The DC / AC conversion circuit 208 can convert the compensated DC voltage to an AC voltage supply for powering the photoionization detector lamp 204. As Figure 2As shown, the DC / AC conversion circuit 208 may include an oscillation circuit 214 and a transformer circuit 216. The oscillation circuit 214 and the transformer circuit 216 may be electronically coupled to each other.

[0053] In some examples, the oscillation circuit 214 is electronically coupled to the DC / DC converter 212 of the DC / DC converter circuit 206 and may be configured to convert a DC voltage into an AC voltage. For example, the oscillation circuit 214 may receive a compensated DC voltage from the DC / DC converter 212 and may convert the compensated DC voltage into a first AC voltage. The example structure of the oscillation circuit 214 will be further illustrated and described hereinafter in conjunction with at least Figure 3 , Figure 4 and Figure 5 .

[0054] In some examples, the transformer circuit 216 is electronically coupled to the oscillation circuit 214 and may be configured to convert a low AC voltage into a high AC voltage. For example, the transformer circuit 216 may receive the first AC voltage from the oscillation circuit 214 and may convert the first AC voltage into a second AC voltage (i.e., the AC voltage supply for the photoionization detector lamp), where the second AC voltage may be higher than the first AC voltage. In addition, the transformer circuit 216 may provide the second AC voltage as an AC voltage supply to power the photoionization detector lamp 204. The example structure of the transformer circuit 216 will be further illustrated and described hereinafter in conjunction with at least Figure 3 , Figure 4 and Figure 5 .

[0055] Referring back to Figure 2 , the feedback circuit 210 may obtain a reference AC voltage associated with the AC voltage supply for the photoionization detector lamp 204 and may convert the reference AC voltage into a feedback DC voltage for the DC / DC converter circuit 206. In some examples, the feedback circuit 210 may include a reference voltage conversion circuit 218 and a reference voltage division circuit 220. The reference voltage conversion circuit 218 and the reference voltage division circuit 220 may be electronically coupled to each other.

[0056] In some examples, the reference voltage conversion circuit 218 may be configured to convert an AC voltage into a DC voltage. For example, the reference voltage conversion circuit 218 may be electronically coupled to the transformer circuit 216 of the DC / AC conversion circuit 208 and may convert the reference AC voltage into a reference DC voltage. The example structure of the reference voltage conversion circuit 218 will be further illustrated and described hereinafter in conjunction with at least Figure 3 , Figure 4 and Figure 5 .

[0057] In some examples, the reference voltage dividing circuit 220 may be configured to convert a high DC voltage into a low DC voltage. For example, the reference voltage dividing circuit 220 may convert a reference DC voltage into a feedback DC voltage and may provide the feedback DC voltage to the DC / DC converter 212 of the DC / DC converter circuit 206. As described above, the DC / DC converter 212 may convert an input DC voltage into a compensated DC voltage at least partially based on the feedback DC voltage. The following will further illustrate and describe an example structure of the reference voltage dividing circuit 220 in conjunction with at least Figure 3 , Figure 4 and Figure 5 .

[0058] Although Figure 2 the example system 200 is illustrated as including a DC / DC converter circuit 206, a DC / AC conversion circuit 208, and a feedback circuit 210, it should be noted that the example systems and devices of the present disclosure may include fewer circuits or more circuits without departing from the scope of the present disclosure. For example, the example system may additionally include a switch circuit configured to turn on / off the example system. As another example, the example device may include a DC / DC converter circuit 206 and a feedback circuit 210, but not a DC / AC conversion circuit 208.

[0059] Now referring to Figure 3 , Figure 4 and Figure 5 , example circuit diagrams according to various embodiments of the present disclosure are shown. In particular, Figure 3 , Figure 4 and Figure 5 may illustrate various example structures of the example systems and devices described above.

[0060] Figure 3 Illustrates an example structure of a system and a device according to the present disclosure. For example, the example system may include a switch circuit 307, a DC / DC converter circuit 301, a DC / AC conversion circuit 303, and a feedback circuit 305.

[0061] In the embodiment shown in Figure 3 , the switch circuit 307 may include an integrated circuit (IC) switch (U3). The IC switch (U3) may include a VIN pin (A1), a VOUT pin (A2), an EN pin (B1), and a GND pin (B2). In some examples, the GND pin (B2) may be connected to ground.

[0062] The VIN pin (A1) may receive an input DC voltage from a DC voltage source. For example, as Figure 3As shown, the VIN pin (A1) can receive an input DC voltage of 3.3 volts. In some other examples, the input DC voltage can have other values.

[0063] The EN pin (B1) can be configured to turn on or off the IC switch (U3), for example, based on whether a control signal CTRL1 is received. When the IC switch (U3) is turned off, the VOUT pin (A2) of the IC switch (U3) may not supply voltage to the DC / DC converter circuit 301. When the IC switch (U3) is turned on, it can supply the input DC voltage to the DC / DC converter circuit 301 via the VOUT pin (A2).

[0064] Referring back to Figure 3 , the input DC voltage can be received at the VIN pin (6) of the DC / DC converter (U2) in the DC / DC converter circuit 301. The DC / DC converter (U2) can also receive a feedback DC voltage from the feedback circuit 305 via the FBX pin (1) of the DC / DC converter (U2). Based on the input DC voltage and the feedback DC voltage, the DC / DC converter (U2) can supply a compensated voltage to the DC / AC conversion circuit 303, the details of which are described below.

[0065] In addition, in the embodiment as shown in Figure 3 , the DC / DC converter (U2) can include a pair of ground pins: GND pin (5) and GND pin (9), which can be connected to ground. Additionally or alternatively, the DC / DC converter (U2) can include a pair of switch pins: SW pin (3) and SW pin (4), which can be connected to the Schottky diode (D2). Additionally or alternatively, the DC / DC converter (U2) can include an NC pin (2) that is not connected. Additionally or alternatively, the DC / DC converter (U2) can include an INTVCC pin (7), and the INTVCC pin (7) is connected to ground via a capacitor (C15) for internal voltage supply.

[0066] As described above, the DC / DC converter (U2) can supply the compensated DC voltage to the DC / AC conversion circuit 303. The DC / AC conversion circuit 303 can include an oscillation circuit and a transformer circuit. The oscillation circuit and the transformer circuit can be electronically coupled to each other.

[0067] The oscillation circuit of the DC / AC conversion circuit 303 can convert the compensated DC voltage into a first AC voltage. In the example as shown in Figure 3In the embodiment shown, the oscillator circuit may include electrical components such as switching transistor elements (Q1), capacitor elements (C2), (C10), and (C11), and resistor elements (R5) and (R6), which are electronically coupled as Figure 3 shown. In some examples, each of the capacitor elements (C10) and (C11) may have a capacitance between 0.1 nanofarad (inclusive) and 10 nanofarad (inclusive). In some examples, the capacitor element (C2) may have a capacitance between 1 nanofarad (inclusive) and 100 nanofarad (inclusive). In some examples, each of the resistor elements (R5) and (R6) may have a resistance between 10 kiloohm (inclusive) and 100 kiloohm (inclusive).

[0068] The transformer circuit of the DC / AC conversion circuit 303 may convert the first AC voltage received from the oscillator circuit into a second AC voltage (i.e., the AC voltage supply for the photoionization detector lamp), where the second AC voltage is higher than the first AC voltage. In Figure 3 the embodiment shown, the transformer circuit may include a transformer (T1) that is electronically coupled as Figure 3 shown. The transformer (T1) may include a primary winding and a secondary winding. The primary winding may be electrically coupled to the oscillator circuit, and the secondary winding may be electronically coupled to the photoionization detector lamp to provide a voltage supply. Each of the primary winding and the secondary winding may include a metal coil having one or more turns.

[0069] As described above, various factors may affect the voltage supply to the photoionization detector lamp. For example, the voltage between the start turn (4) and the end turn (8) of the secondary winding of the transformer (T1) may fluctuate due to changes in the electrical properties of the electrical components caused by an increase in temperature. In this regard, various embodiments of the present disclosure may obtain a reference AC voltage from the secondary winding of the transformer (T1).

[0070] In Figure 3 the embodiment shown, the transformer (T1) may include a transformer tap (6) that is connected to the secondary winding and is positioned between the start turn (4) and the end turn (8) of the secondary winding. The voltage between the start turn (4) and the transformer tap (6) is proportional to the voltage between the start turn (4) and the end turn (8).

[0071] In other words, when the voltage supply to the photoionization detector lamp changes (i.e., the voltage change between the start turn (4) and the end turn (8)), the voltage between the start turn (4) and the transformer tap (6) also changes proportionally. Thus, the voltage between the start turn (4) and the transformer tap (6) can be used as a reference AC voltage, which reflects the actual change in the voltage supply to the photoionization detector lamp.

[0072] The transformer tap (6) can be positioned at a location between the start turn (4) and the end turn (8) such that the reference AC voltage can fall within a suitable range for the feedback circuit 305. In some examples, the transformer tap (6) is positioned between 5% (inclusive) and 20% (inclusive) of the secondary winding of the transformer (T1) (i.e., the voltage between the start turn (4) and the transformer tap (6) is between 5% (inclusive) and 20% (inclusive) of the voltage between the start turn (4) and the end turn (8)).

[0073] In some examples, the transformer tap (6) is positioned at 6% of the secondary winding of the transformer (T1). In other words, the voltage between the start turn (4) and the transformer tap (6) is 6% of the voltage between the start turn (4) and the end turn (8). For example, if the voltage between the start turn (4) and the end turn (8) is 600 volts, the voltage between the start turn (4) and the transformer tap (6) can be 40 volts (which can be used as a reference AC voltage for the feedback circuit 305).

[0074] As Figure 3 shown, the feedback circuit 305 is electronically coupled to the transformer tap (6) of the secondary winding and receives the reference AC voltage. The feedback circuit 305 can include a reference voltage conversion circuit and a reference voltage division circuit. The reference voltage conversion circuit and the reference voltage division circuit can be electronically coupled to each other.

[0075] The reference voltage conversion circuit of the feedback circuit 305 can convert the reference AC voltage into a reference DC voltage. When the reference AC voltage changes, the converted reference DC voltage changes proportionally.

[0076] In the embodiment as Figure 3 shown, the reference voltage conversion circuit can include a diode element (D1) and a capacitor element (C13). The diode element (D1) and the capacitor element (C13) can be electronically coupled to each other. In particular, the diode element (D1) can be electronically coupled to the transformer tap (6) of the transformer (T1) in the DC / AC conversion circuit 303, and the capacitor element (C13) can be connected to ground. In some examples, the capacitor element (C13) has a capacitance between 1 nanofarad (inclusive) and 100 nanofarads (inclusive).

[0077] The reference voltage dividing circuit of the feedback circuit 305 can convert a reference DC voltage into a corresponding feedback DC voltage, which can be lower than the reference DC voltage. When the reference DC voltage changes, the converted feedback DC voltage changes proportionally.

[0078] In the embodiment shown in Figure 3 the reference voltage dividing circuit can include a resistor element (R13) and a resistor element (R18). The resistor element (R13) and the resistor element (R18) can be electronically coupled to each other. In particular, the resistor element (R13) can be electronically coupled between the diode element (D1) and the capacitor element (C13) of the reference voltage conversion circuit, and the resistor element (R18) can be electronically coupled between the DC / DC converter (U2) of the DC / DC converter circuit 301 and the resistor element (R13). In some examples, each of the resistor element (R13) and the resistor element (R18) can have a resistance between 100 kiloohms (inclusive) and 10 megohms (inclusive).

[0079] As shown in Figure 3 the FBX pin (1) of the DC / DC converter (U2) can receive the feedback DC voltage from the feedback circuit 305. As described above, the feedback DC voltage is converted by the feedback circuit 305 based on the reference AC voltage from the DC / AC conversion circuit 303. When the reference AC voltage changes, the feedback DC voltage changes proportionally. Thus, the feedback DC voltage received by the DC / DC converter (U2) reflects the actual change in the voltage supply to the photoionization detector lamp.

[0080] Based on the feedback DC voltage, the DC / DC converter (U2) can correspondingly adjust the compensated voltage supplied to the DC / AC conversion circuit 303. For example, when the feedback DC voltage is lower than a predetermined value, the DC / DC converter (U2) can (step by step) increase the compensated voltage until the feedback DC voltage reaches the predetermined value. When the feedback DC voltage is higher than the predetermined value, the DC / DC converter (U2) can (step by step) decrease the compensated voltage until the feedback DC voltage drops to the predetermined value. In some examples, when the feedback DC voltage is at the predetermined value, it indicates that the corresponding AC voltage supply to the photoionization detector lamp is at the desired level.

[0081] Although Figure 3 illustrates that the DC / DC converter (U2) can adjust the compensated DC voltage through the EN / UVLO pin (8) under voltage blocking, it should be noted that the scope of the present disclosure is not limited to as Figure 3the embodiments shown in, and other suitable DC / DC converters may be implemented without departing from the scope of the present disclosure to regulate the compensated DC voltage based on the feedback DC voltage.

[0082] Now referring to Figure 4 , an example structure of a system and apparatus according to the present disclosure is illustrated. For example, an example system may include a switching circuit 408, a DC / DC converter circuit 402, a DC / AC conversion circuit 303, and a feedback circuit 406.

[0083] In some examples, Figure 4 the switching circuit 408, the DC / DC converter circuit 402, and the DC / AC conversion circuit 404 of Figure 3 may be similar to the switching circuit 307, the DC / DC converter circuit 301, and the DC / AC conversion circuit 303 described above in connection with

[0084] In addition, Figure 4 the feedback circuit 406 of Figure 3 may include a reference voltage conversion circuit and a reference voltage division circuit, which are similar to the reference voltage conversion circuit and the reference voltage division circuit described above in connection with

[0085] In some examples, the microcontroller unit may be an integrated circuit that includes a processing circuit and a memory circuit electronically coupled to each other. The memory circuit may be a non-transitory memory storing computer program instructions, and the computer program instructions may be executed by the processing circuit.

[0086] In some examples, the microcontroller unit may perform various functions associated with the feedback circuit 406. For example, the microcontroller unit may monitor the feedback DC voltage from the reference voltage division circuit and trigger a warning (such as an audio alert through a speaker element connected to the processing circuit) when the feedback DC voltage indicates that the photoionization detector lamp is powered by an insufficient or excessive voltage supply.

[0087] Now referring to Figure 5 , an example structure of a system and apparatus according to the present disclosure is illustrated. For example, an example system may include a switching circuit 507, a DC / DC converter circuit 501, a DC / AC conversion circuit 503, and a feedback circuit 505.

[0088] In some examples, Figure 5The switching circuit 507, DC / DC converter circuit 501, and DC / DC to AC conversion circuit 503 can be similar to the switching circuit 307, DC / DC converter circuit 301, and DC / DC to AC conversion circuit 303 described above in connection with Figure 3 Figure Figure 3 .

[0089] In addition, Figure 5 the feedback circuit 505 of can include a reference voltage conversion circuit and a reference voltage division circuit, which are similar to the reference voltage conversion circuit and the reference voltage division circuit described above in connection with Figure 3 Figure Figure 3 . The feedback circuit 505 can further include an amplifier element that is electronically coupled to the reference voltage division circuit and the DC / DC converter (U2) of the DC / DC converter circuit 501. In the embodiment shown in Figure 5 Figure Figure 5 , the amplifier element can be a closed-loop amplifier that can provide, for example, a more constant feedback DC voltage to the DC / DC converter (U2) of the DC / DC converter circuit.

[0090] Now referring to Figure 6 , Figure 7 , Figure 8 and Figure 9 , various example alternating current (AC) waveforms showing the circuit output voltage are provided. In particular, the same input voltage is provided to the Figure 6 , Figure 7 , Figure 8 , and Figure 9 circuits.

[0091] Figure 6 and Figure 7 illustrate the AC waveforms of circuits of embodiments that do not implement the present disclosure. In Figure 6 Figure Figure 6 , the photoionization detector lamp is not connected to the circuit; in Figure 7 Figure Figure 7 , the photoionization detector lamp is connected to the circuit. In some examples, Figure 6 the peak-to-peak voltage V1 in pp Figure pp Figure 7 can be 1.30 kilovolts, and pp the peak-to-peak voltage V2 in

[0092] Figure 8 and Figure 9 illustrate the AC waveforms of circuits of example embodiments that implement the present disclosure. In Figure 8 Figure Figure 8 , the photoionization detector lamp is not connected to the circuit; in Figure 9 Figure Figure 9 , the photoionization detector lamp is connected to the circuit. In some examples, Figure 8The peak-to-peak voltage V3pp therein can be 1.31 kilovolts, and Figure 9 the peak-to-peak voltage V4pp therein can be 1.30 kilovolts. In other words, in the circuits implementing the embodiments of the present disclosure, the photoionization detector lamp can cause a voltage drift of less than 1%.

[0093] Compare Figure 6 - 7 the peak-to-peak voltage difference between and in Figure 8 - 9 the peak-to-peak voltage difference between, and note that various embodiments of the present disclosure can reduce the voltage drift in providing voltage supply to the photoionization detector lamp.

[0094] Various embodiments of the present disclosure can be embodied as a method for providing an alternating current (AC) voltage supply to a photoionization detector (PID) lamp. In this regard, Figure 10 FIG. depicts a flowchart illustrating an example method according to various embodiments of the present disclosure.

[0095] In some examples, each block of the flowchart, as well as combinations of blocks in the flowchart, can be implemented by various means, such as hardware, firmware, circuitry, and / or other devices associated with the execution of software including one or more computer program instructions.

[0096] In some examples, Figure 10 one or more of the processes described in can be embodied by computer program instructions that can be stored in a memory circuit (such as a non-transitory memory) of a system employing the embodiments of the present disclosure and executed by a processing circuit (such as a processor) of the system. These computer program instructions can direct the system to operate in a specific manner such that the instructions stored in the memory circuit produce an article of manufacture, the execution of which implements the functions specified in the (multiple) flowchart blocks. Additionally, the system can include one or more other circuits, such as, for example, the DC / DC converter circuit, the DC / AC conversion circuit, and the feedback circuit described above in connection with Figure 2 , Figure 3 , Figure 4 and Figure 5 . The various circuits of the system can be electronically coupled to each other and / or therein to transfer and / or receive energy, data, and / or information.

[0097] In some examples, the embodiments can take the form of a computer program product on a non-transitory computer-readable storage medium storing computer-readable program instructions (such as computer software). Any suitable computer-readable storage medium can be utilized, including non-transitory hard disks, CD-ROMs, flash memories, optical storage devices, and / or magnetic storage devices.

[0098] Now refer to Figure 10 which illustrates an example method 1000 according to some embodiments of the present disclosure. Method 1000 begins at 1002.

[0099] At block 1004, a feedback circuit of an example device (such as, for example, feedback circuit 210, feedback circuit 305, feedback circuit 406, and feedback circuit 505 described above in connection with Figure 2 , Figure 3 , Figure 4 and Figure 5 ) may obtain a reference alternating current (AC) voltage associated with a photoionization detector lamp. For example, the feedback circuit may obtain the reference AC voltage from a direct current (DC) voltage to AC voltage (DC / AC) conversion circuit that is electronically coupled to the photoionization detector lamp.

[0100] In some examples, the DC / AC conversion circuit may include a transformer that provides an AC voltage supply to the photoionization detector lamp through a secondary winding. In such examples, the reference AC voltage may be a voltage lower than the AC voltage supply, and as the AC voltage supply changes, the reference AC voltage may change proportionally.

[0101] At block 1006, a feedback circuit of an example device (such as, for example, feedback circuit 210, feedback circuit 305, feedback circuit 406, and feedback circuit 505 described above in connection with Figure 2 , Figure 3 , Figure 4 and Figure 5 ) may convert the reference AC voltage into a feedback direct current (DC) voltage.

[0102] In some examples, the feedback circuit may convert the reference AC voltage into a feedback DC voltage via a reference voltage conversion circuit and a reference voltage division circuit, as described above. In some examples, as the reference AC voltage changes, the feedback DC voltage may change proportionally.

[0103] At block 1008, a DC voltage to DC voltage (DC / DC) converter circuit of an example device (such as, for example, DC / DC converter circuit 206, DC / DC converter circuit 301, DC / DC converter circuit 402, and DC / DC converter circuit 501 described above in connection with Figure 2 , Figure 3 , Figure 4 and Figure 5 ) may convert an input DC voltage into a compensated DC voltage based at least in part on the feedback DC voltage.

[0104] In some examples, when the feedback DC voltage is below a predetermined value, the DC / DC converter can (stepwise) increase the compensated voltage until the feedback DC voltage reaches the predetermined value. In some examples, when the feedback DC voltage is above a predetermined value, the DC / DC converter (U2) can (stepwise) decrease the compensated voltage until the feedback DC voltage drops to the predetermined value.

[0105] At block 1010, the DC / DC converter circuit of the example apparatus (such as, for example, the DC / DC converter circuit 206, the DC / DC converter circuit 301, the DC / DC converter circuit 402, and the DC / DC converter circuit 501 described above respectively in connection with Figure 2 , Figure 3 , Figure 4 and Figure 5 ) can cause the supply of the compensated DC voltage to the DC / AC conversion circuit. In some examples, the DC / AC conversion circuit can convert the compensated DC voltage into an AC voltage supply for use in the photoionization detector lamp.

[0106] Method 1000 ends at block 1012.

[0107] It is to be understood that the present disclosure is not limited to the particular embodiments disclosed, and modifications and other embodiments are intended to be included within the scope of the appended claims. Although specific terms are employed herein, they are used only in a general and descriptive sense and not for purposes of limitation, unless otherwise described.

Claims

1. An apparatus for providing a voltage supply to a photoionization detector lamp, the apparatus comprising: A DC voltage to DC voltage (DC / DC) converter circuit including a DC / DC converter, wherein the DC / DC converter is electronically coupled to a direct current (DC) voltage source and converts an input DC voltage from the DC voltage source into a compensated DC voltage based at least in part on a feedback DC voltage; A DC voltage to AC voltage (DC / AC) conversion circuit electrically coupled to the DC / DC converter, the DC / AC conversion circuit including an oscillation circuit and a transformer circuit electrically coupled to each other, wherein the DC / AC conversion circuit is configured to convert the compensated DC voltage into an AC voltage supply for the photoionization detector lamp; And A feedback circuit electronically coupled to the DC / DC converter circuit and a transformer tap of a secondary winding of the transformer circuit of the DC / AC conversion circuit, wherein the feedback circuit obtains a reference alternating current (AC) voltage associated with the DC / AC conversion circuit and converts the reference AC voltage into a feedback DC voltage for the DC / DC converter.

2. The apparatus according to claim 1, wherein the oscillation circuit is electronically coupled to the DC / DC converter, and wherein the transformer circuit is electronically coupled to the photoionization detector lamp.

3. The apparatus according to claim 1, wherein the feedback circuit includes a reference voltage conversion circuit and a reference voltage division circuit electronically coupled to each other, wherein the reference voltage conversion circuit is electronically coupled to the transformer tap of the secondary winding of the transformer circuit, and wherein the reference voltage division circuit is electronically coupled to the DC / DC converter.

4. The apparatus according to claim 3, wherein the reference voltage conversion circuit converts the reference AC voltage into a reference DC voltage, and wherein the reference voltage division circuit converts the reference DC voltage into a feedback DC voltage and provides the feedback DC voltage to the DC / DC converter.

5. The apparatus according to claim 3, wherein the transformer circuit further includes a primary winding in addition to the secondary winding.

6. The apparatus according to claim 1, wherein the transformer tap is positioned between 5% (inclusive) and 20% (inclusive) of the secondary winding of the transformer circuit.

7. The apparatus according to claim 6, wherein the transformer tap is positioned at 6% of the secondary winding of the transformer circuit.

8. The apparatus according to claim 3, wherein the reference voltage conversion circuit includes a diode element and a capacitor element electronically coupled to each other, and wherein the diode element is electronically coupled to the transformer circuit.

9. The apparatus according to claim 8, wherein the capacitor element has a capacitance between 1 nanofarad (inclusive) and 100 nanofarads (inclusive).

10. The apparatus according to claim 3, wherein the reference voltage division circuit includes two resistor elements electronically coupled to each other.

11. The apparatus according to claim 10, wherein each of the two resistor elements has a resistance between 100 kiloohms (inclusive) and 10 megohms (inclusive).

12. The apparatus according to claim 1, further comprising a switching circuit electronically coupled to the DC / DC converter.

13. The apparatus according to claim 1, wherein the feedback circuit includes a microcontroller unit electrically coupled to the DC / DC converter.

14. The apparatus according to claim 1, wherein the feedback circuit includes an amplifier element electronically coupled to the DC / DC converter.

15. A system for providing an alternating current (AC) voltage supply to a photoionization detector lamp from a DC voltage source having an input direct current (DC) voltage, the system comprising: A DC voltage to DC voltage (DC / DC) converter circuit including a DC / DC converter, wherein the DC / DC converter is electronically coupled to the DC voltage source and converts the input DC voltage into a compensated DC voltage based at least in part on a feedback DC voltage; A DC voltage to AC voltage (DC / AC) conversion circuit electronically coupled to the DC / DC converter circuit and the photoionization detector lamp, the DC / AC conversion circuit including an oscillation circuit and a transformer circuit electrically coupled to each other, wherein the DC / AC conversion circuit converts the compensated DC voltage into an AC voltage supply for the photoionization detector lamp; And A feedback circuit electronically coupled to the DC / DC converter circuit and a transformer tap of a secondary winding of the transformer circuit of the DC / AC conversion circuit, wherein the feedback circuit obtains a reference AC voltage associated with the AC voltage supply and converts the reference AC voltage into a feedback DC voltage for the DC / DC converter.

16. The system according to claim 15, wherein the oscillation circuit is electronically coupled to the DC / DC converter, and wherein the transformer circuit is electronically coupled to the photoionization detector lamp.

17. The system according to claim 15, wherein the feedback circuit includes a reference voltage conversion circuit and a reference voltage division circuit electronically coupled to each other, wherein the reference voltage conversion circuit is electronically coupled to the transformer tap of the secondary winding of the transformer circuit, and wherein the reference voltage division circuit is electronically coupled to the DC / DC converter.

18. The system according to claim 17, wherein the reference voltage conversion circuit converts the reference AC voltage into a reference DC voltage, and wherein the reference voltage division circuit converts the reference DC voltage into a feedback DC voltage and provides the feedback DC voltage to the DC / DC converter.

19. The system according to claim 15, wherein the transformer circuit further includes a primary winding in addition to the secondary winding.

20. A method for providing an alternating current (AC) voltage supply to a photoionization detector lamp from a DC voltage source having an input direct current (DC) voltage, the method comprising: A reference AC voltage associated with a DC voltage to AC voltage (DC / AC) conversion circuit that is electronically coupled to a photoionization detector lamp is obtained through a feedback circuit; The reference AC voltage is converted into a feedback DC voltage through the feedback circuit; An input DC voltage is converted into a compensated DC voltage by a DC voltage to DC voltage (DC / DC) converter circuit at least partially based on the feedback DC voltage, The compensated DC voltage is caused to be supplied to the DC / AC conversion circuit by the DC / DC converter circuit; and The compensated DC voltage is converted into an AC voltage source for the photoionization detector lamp by the DC / AC conversion circuit; wherein the DC / AC conversion circuit is electrically coupled to the DC / DC converter circuit, the DC / AC conversion circuit includes an oscillation circuit and a transformer circuit that are electrically coupled to each other, and The feedback circuit is electrically coupled to the DC / DC converter circuit and a transformer tap of the secondary winding of the transformer circuit of the DC / AC conversion circuit.

Images