KR100901156B1 - Fuel Cell Electronic Loader - Google Patents

Abstract

The present disclosure relates to an electronic loader for a fuel cell, and includes a constant current, a constant voltage, a constant resistance, a constant power, a dynamic signal, and a key signal for evaluating the performance of a fuel cell including setting a current, voltage, and maximum power value according to a set mode. Key operation unit for generating; When the key signal for the performance evaluation of the fuel cell is input from the key control unit, the controller controls the PI control to measure the output characteristics of the connected fuel cell for performance evaluation according to the set mode, and the voltage and current data measured through the PI control are measured. Collect and control the amount of current and at the same time perform protection functions including overcurrent, overvoltage, overpower, overheating and reverse, and display the output characteristic information of voltage and current according to the currently set mode measured under PI control A microcontroller for controlling; A loader module including a field effect transistor, a distribution resistor, a heat sink, and measuring a current and a voltage of a fuel cell connected for performance evaluation; In order to minimize the deviation of the data measured in the loader module under the control of the microcontroller, the loader module is controlled by the PI control that feeds back and outputs the measured data from the loader module to be equal to the reference data input from the microcontroller. An analog board unit configured to output the voltage and current data measured by the loader module to the microcontroller according to the present invention; A display unit displaying mode setting state information of the electronic loader and a current operating state, and displaying voltage and current values measured by the loader module through PI control of the analog board unit according to the control of the microcontroller; An interface unit for inputting key signals for evaluating the performance of the PC and the fuel cell connected to the outside under the control of the microcontroller, and outputting voltage and current data measured by the loader module according to PI control of the analog board unit; And a boost power supply unit supplying a voltage for performing performance evaluation on the fuel cell of each cell unit so that the electronic loader can always operate even at a low voltage.

Therefore, the present invention has an effect that can easily perform performance evaluation of the fuel cell of each cell unit through a separate boost power supply at a low voltage and high current that can not be performed in the conventional electronic loader.

Fuel Cell, Electronic Loader, PI Control, Voltage, Current, Performance, Evaluation

Description

Electronic loader for fuel cell

The present invention relates to an electronic loader for a fuel cell.

More specifically, the present invention relates to an electronic loader for fuel cells that performs performance evaluation by measuring voltage and current of a fuel cell operating at a low voltage and a high current with a PI (Proportional Integral) control method.

Fossil fuels, which make up the vast majority of primary energy sources currently in use, are a finite resource that emits large amounts of environmental pollutants and will eventually be depleted.

Accordingly, solar energy, wind power, hydropower, geothermal energy, etc. have been suggested as alternative energy for fossil fuels, but have a disadvantage in that they cannot be used as direct fuels due to the difference in geographical distribution.

However, since hydrogen is an almost infinite energy resource in itself and has no environmental pollution, and most of all, it is free to convert into electrical energy, mechanical energy, and thermal energy. Therefore, hydrogen is an energy source to replace fossil fuel. Interest is growing.

Since hydrogen exists in the form of fossil fuels such as petroleum, coal, and natural gas, water, and biomass, production costs are excessive, environmental pollution may occur during production, and storage and transportation are difficult. The commercialization has been delayed, but the emergence of fuel cells has changed the way we see hydrogen energy.

A fuel cell is a device that converts hydrogen into electrical energy and thermal energy by chemical reaction. Hydrogen may be used directly or hydrogen obtained through reforming of gasoline, methanol, natural gas, or the like. Even when reforming is adopted, the environmental pollution can be greatly reduced.

Fuel cells also have the potential to revolutionize existing energy systems, although hydrogen-using technologies will have to evolve. Many countries now emphasize the transition to a hydrogen-based economy, and that is why fuel cells are a key component technology.

Depending on the electrolyte used, the fuel cell has a phosphoric acid type (PAFC, Phosphoric Acid Fuel Cell), molten carbonate type (MCFC, Molten Carbonate Fuel Cell), solid oxide type (SOFC, Solid Oxide Fuel Cell), solid polymer type (PEMFC, Proton) Exchange Membrane Fuel Cell) and Direct Methanol Fuel Cell (DMFC).

Early fuel cells have been commercialized mainly for large fuel cells such as phosphoric acid type, and these large fuel cells operating at high temperatures are known to have been verified to some extent for cogeneration and distributed power generation. However, despite the environmental friendliness and almost twice the energy efficiency, due to the three to five times higher generation cost than the existing power source, the institution that the stable supply of electric power plays an important role mainly in public institutions, hospitals, banks, and information processing centers. In particular, limited demand expansion is taking place around companies.

On the other hand, as the demand for mobile power source increases, solid polymer type, direct methanol type, etc. have been in the spotlight recently. The solid polymer type is showing the fastest growth as a major market, and as the miniaturization progresses, the market is expanding to various mobile devices.

Direct methanol is mainly developed for small portable devices such as notebook PCs and mobile phones, and is expected to be commercially available in the next 1-2 years. Fuel cells are building their status as nominal all-weather energy sources, from small devices such as mobile phones to power sources for cars and power generation.

When mass producing fuel cells, equipment for evaluating the performance of fuel cells is essential. Equipment that performs this role is sometimes called a fuel cell evaluation system. In general, a fuel cell evaluation system is a fuel cell electronic loader, control software for driving and monitoring the electronic loader, and a main controller (PC) to control the entire evaluation system. ), An interface system and software for communicating between components (sensors and devices) of a test station.

Among the equipment constituting the fuel cell performance evaluation system, the electronic loader is the core equipment used for the performance evaluation of the fuel cell, and forcibly consumes the power generated from the fuel cell at an arbitrary operating point (that is, It converts into heat energy and dissipates) so that the output characteristics of the fuel cell to be evaluated can be inspected by measuring voltage and current.

Electronic loader should be able to stably apply low voltage of 0 ~ 3V and high current of 20 ~ 30A due to the output characteristics of fuel cell.The precision should be relatively high because voltage of less than 3V and high current of 30A are applied. do.

Existing general electronic loaders can evaluate the performance of the entire fuel cell, but fuel cells are typically a series of cells connected in parallel and can be used by stacking cells according to the required voltage and current. In this case, if the failure occurs at any one part, the lifespan is very short, which can lead to the failure of the equipment. Therefore, the equipment that can measure the voltage per cell is needed to select the specific cell that causes the failure. Do.

However, the conventional electronic loader, there is no product that can measure the low voltage of each cell of the fuel cell as described above. That is, in order to measure the voltage of 0.5-0.9V of the cell, the electronic loader must operate at a lower voltage, but the conventional electronic loader is difficult to measure because the minimum voltage is operated at 1.5V or more. The reason is that since the circuit configuration of the electronic loader is composed of semiconductor elements such as transistors (TRs), field effect transistors (FETs), and ICs, a minimum voltage supply is required to operate them. Therefore, it is difficult to measure voltage and current for evaluating fuel cell performance of each cell using a general electronic loader without a separate power supply (ie, boost power).

In addition, although many companies around the world are developing fuel cells, there is no standard system for system evaluation for testing and evaluating fuel cells. As a result, it was difficult to cope with the fuel cell market, which is expected to increase rapidly in the future.

In order to solve the above problems, the object of the present invention is to perform a stable and precise performance evaluation of a fuel cell by using a PI control method, and at the same time, a low voltage (0 to 1.5 V) and It is possible to evaluate the performance of fuel cells in individual cell units through a separate power supply (i.e., boost power) at high current (0 ~ 30A), and it is possible to develop an electronic loader for fuel cells that improves accuracy and resolution. To provide.

Another object of the present invention is to be able to test a lot of equipment at the same time in a small space during mass production of fuel cells, easy to expand, select and manufacture only the functions necessary for fuel cell measurement, significantly reducing the manufacturing cost, overheat prevention and system The present invention provides a fuel cell electronic loader having various protection functions (overcurrent, overvoltage, overpower, overheating, reverse connection, etc.) for protection.

Another object of the present invention, the user can easily set the input value (voltage, current, time, mode selection, etc.), provides a real-time monitoring graph using a GUI program to observe the operation step by step at a glance, and automatically It is possible to provide unmanned observation when it is set as a setting, and to provide a fuel cell electronic loader that makes it easy to check the abnormality of equipment by real-time backup of measurement data such as measurement time, current, voltage, etc. by time.

The fuel cell electronic loader according to the present invention for achieving the above object, the performance of the fuel cell including the setting of the constant current, constant voltage, constant resistance, constant power, dynamic mode, the setting of the current, voltage, power maximum value according to the set mode A key operating unit for generating a key signal for evaluation; When the key signal for the performance evaluation of the fuel cell is input from the key control unit, the controller controls the PI control to measure the output characteristics of the connected fuel cell for performance evaluation according to the set mode, and the voltage and current data measured through the PI control are measured. It controls the amount of current collected and performs protection functions including overcurrent, overvoltage, overpower, overheating and reverse connection, and controls the display of the output characteristics information of voltage and current according to the currently set mode measured according to PI control. A microcontroller; A loader module including a field effect transistor, a distribution resistor, a heat sink, and measuring a current and a voltage of a fuel cell connected for performance evaluation; In order to minimize the deviation of the data measured in the loader module under the control of the microcontroller, the loader module is controlled by the PI control that feeds back and outputs the measured data from the loader module to be equal to the reference data input from the microcontroller. An analog board unit configured to output the voltage and current data measured by the loader module to the microcontroller according to the present invention; A display unit displaying mode setting state information of the electronic loader and a current operating state, and displaying voltage and current values measured by the loader module through PI control of the analog board unit according to the control of the microcontroller; An interface unit for inputting key signals for evaluating the performance of the PC and the fuel cell connected to the outside under the control of the microcontroller, and outputting voltage and current data measured by the loader module according to PI control of the analog board unit; And a boost power supply unit supplying a voltage for performing performance evaluation of the fuel cell on an individual cell basis so that the electronic loader can always operate even at a low voltage. The analog board unit includes an electronic loader input unit and a current / voltage supply source. A MOSFET for controlling an amount of current to a gate voltage level in order to control a constant current when the output terminal of the terminal is connected to the polarity to perform a mode input from a key control unit; A distribution resistor unit connected to the source terminal side of the MOSFET to perform current sensing; A first amplifying circuit section for amplifying and outputting a voltage at both ends of the distribution resistor section fed back from the MOSFET; A filter for removing noise of the voltage between the both ends of the distribution resistor section amplified by the first amplifier circuit section and outputting the current to the microcontroller for current detection based on the voltage between the both ends of the distribution resistor section in the microcontroller; An integrating circuit unit for receiving a signal amplified by the first amplifying circuit unit and performing PI control to correct the feedback voltage by a reference voltage input from the microcontroller; And a second amplifying circuit unit which amplifies the PI-controlled signal from the integrating circuit unit and the voltage output from the source terminal of the MOSFET and outputs the result to the gate terminal of the MOSFET, wherein the boost voltage supply unit rectifies the AC input power into a DC input voltage. An input rectification smoothing circuit unit which outputs smoothly; Forward switching with a switching IC connected to the transformer primary side, a Schottky diode with a forward voltage of 0.2V to 0.3V, and a FET with low drain-source resistance (Rds) connected to the transformer secondary side at turn-on to compensate for power loss. A switching converter circuit portion configured to be rectified and converting the DC input voltage input from the input rectification smoothing circuit portion into a DC output voltage according to the switching control of the switching IC; An output rectification smoothing circuit unit for smoothing the DC output voltage output from the switching converter circuit unit to the electronic loader; And a feedback control circuit for stabilizing the DC output voltage input from the output rectification smoothing circuit.

At this time, the above-described key operation unit, power supply on / off key, constant current, constant voltage, constant resistance, constant power, dynamic mode setting key, remote sensing operation key, current, voltage, power maximum value setting and sound activation / Menu keys for setting the deactivation function, navigation keys for moving the cursor position to the left and right, selection keys for activating / deactivating the selected mode, enter key for storing the input value and jog dial for adjusting the input value. It is preferable to comprise.

 The analog board unit may further include a comparator configured to detect whether the voltage deviation of the FET connected between the input terminal and the distribution resistor unit is reversed and output to the microcontroller in order to protect the circuit device according to the reverse connection. can do.

In addition, the distribution resistor unit may be configured by connecting five resistors in parallel, and the first amplifier circuit unit includes a plurality of resistors, capacitors, and non-inverting amplifiers, and voltages at both ends of the distribution resistor unit are applied to the non-inverting terminals of the non-inverting amplifiers. When the amplified circuit is amplified and output to the integrating circuit part, the integrating circuit part is composed of a plurality of resistors, capacitors, and integrators. It is preferable to configure a PI control for correcting the feedback voltage by the reference voltage of the input microcontroller to output to the second amplifying circuit unit. The second amplifying circuit unit is composed of a plurality of resistors and non-inverting amplifiers. It is applied to the non-inverting terminal of the non-inverting amplifier and the output voltage of the source terminal of the MOSFET inputted to the inverting terminal. It is preferable to configure the integrated circuit unit to amplify the PI-controlled voltage and output it to the gate terminal of the MOSFET.

As described above, according to the fuel cell electronic loader of the present invention, while performing a performance evaluation of the fuel cell through the PI control method while maintaining high reliability and stability, a low voltage (0 to 1.5 that cannot be performed by the conventional electronic loader) In V) and a high current (0 to 30A), a separate boost power supply can easily perform performance evaluation of a fuel cell in an individual cell unit.

In addition, since it is possible to test a lot of equipment at the same time in a small space, it is easy to expand and adopts only the functions necessary for measuring fuel cells, thereby significantly reducing manufacturing costs, and designing various protection functions for heat protection and system protection. Through this there is an effect that can perform a stable performance evaluation of the fuel cell.

In addition, the user can easily set input values such as voltage, current, time, and mode selection, as well as observe the operation stages at a glance using a GUI program. Real-time backup of the device has an effect that can be easily checked whether there is a problem.

Hereinafter, an electronic loader for a fuel cell of the present invention will be described in detail with reference to the accompanying drawings.

1 is a block diagram schematically showing the configuration of an electronic loader for a fuel cell according to the present invention, FIG. 2 is a block diagram showing in detail the configuration of the analog board unit of FIG. 1, and FIG. 3 is a detailed circuit diagram of the analog board unit of FIG. 4 is a detailed circuit diagram of the boost power supply unit of FIG. 1.

As shown in FIG. 1, the fuel cell electronic loader according to the present invention includes a key operation unit 100, a microcontroller 200, a loader module 300, an analog board unit 400, a display unit 500, and an interface unit 600. ), The boost power supply unit 700 and the like.

The key operation unit 100 is a constant current (constant current, a mode in which the load is constantly applied to a predetermined load value regardless of voltage), a constant voltage (Constant Voltage, a predetermined voltage value, and a predetermined amount of current to maintain a set voltage value at load on Control mode), constant resistance (Constant Resistance, the amount of load is determined by the resistance value, and the load amount is changed by the voltage change), Constant Power (Constant Power, Programmed setting regardless of input voltage) Value mode), dynamic mode (currently set to two values and mode that changes repeatedly over time), current, voltage and power settings according to the set mode. A key signal for evaluating the performance of the fuel cell is generated and output to the microcontroller 200.

The microcontroller 200 stores the driving algorithm of the electronic rod for fuel cell, and when various key signals are input from the key operation unit 100 including the mode setting for the performance evaluation of the fuel cell, the microcontroller 200 performs performance evaluation according to the set mode. Controlling the analog board 400 to control the output characteristics of the fuel cell through the loader module 300 (PI control (control method for controlling the output current (voltage) to have a proportional relationship with the output current (voltage)) And control the amount of current by collecting the voltage and current data measured by the loader module 300 through PI control and at the same time overcurrent (OCP), overvoltage (OVP), overpower (OPP), overheating (OTP) Protection function including reverse connection (REV) and output characteristics information of voltage and current according to the currently set mode measured by the loader module 300 through PI control of the analog board unit 400. Output to) It controls to display open.

At this time, the microcontroller 200 communicates with the analog board 400 through an analog / digital converter (ADC), a digital / analog converter (DAC), collects voltage and current data, and controls the amount of current. The PI control of the analog board unit 400 is precisely controlled based on calibration data stored in an electrically erasable and programmable read only memory (EEPROM) inside the controller 200.

The loader module 300 includes a field effect transistor, a shunt resistance, a heat sink, and measures current and voltage of a fuel cell connected for performance evaluation under the control of the analog board unit 400.

In the loader module 300, the analog board unit 400 is equal to the reference data input from the microcontroller 200 in order to minimize the deviation of data measured by the loader module 300 under the control of the microcontroller 200. The loader module 300 is controlled by a PI control that feeds back the measured data and outputs the voltage and current data measured by the loader module 300 to the microcontroller 200 according to the PI control.

The display unit 500 is composed of LED, VFD (Vacuum Fluorescent Display, etc.), and displays the mode setting state information and the current operation state of the electronic loader, and the analog under the control of the microcontroller 200 Display the voltage and current values measured by the loader module 300 through the PI control of the board unit 400. In addition, when performing various protection functions, a warning message is displayed at the same time as an alarm so that the user can immediately check.

The interface unit 600 inputs a key signal for evaluating the performance of the PC and the fuel cell connected to the outside under the control of the microcontroller 200, and the loader module 300 according to the PI control of the analog board unit 400. Performs output of measured voltage and current data.

The boost power supply 700 supplies a voltage for performing performance evaluation on the fuel cell of each cell unit so that the electronic loader can always operate even at a low voltage. At this time, the characteristics of the boost power supply may affect the electronic loader, so a product with high efficiency and high stability is required, and ripple or noise should be very small. In addition, the capacity of the boost power supply must be designed in accordance with the capacity of the electronic loader, so as the capacity of the electronic loader increases, the capacity of the boost power must also be relatively large.

At this time, the key operation unit 100 is a power supply on / off key 110 for supplying power to the electronic loader, as shown in Figure 6 showing the front and rear parts of the fuel cell electronic loader of the present invention. ), A setting key 120 for setting constant current (CC), constant voltage (CV), constant resistance (CR), constant power (CP) and dynamic mode (DYN), and a remote sensing operation key for operating remote sensing. 130, a menu key 140 for setting a current, voltage, power maximum value, and sound activation / deactivation function, a movement key 150 for moving the cursor position left / right, and activation / deactivation of a selected mode And a selection key 160, an enter key 170 for storing the input value, a jog dial 180 for adjusting the input value, and the like.

2 and 3, the analog board unit 400 includes a metal-oxide semiconductor field effect transistor (MOSFET) 410 and a distribution resistor (shunt). resistance unit 420, first amplifier circuit unit 430, filter 440, integrating circuit unit 450, second amplifier circuit unit 460, field effect transistor (hereinafter referred to as FET) 470 , The comparator 480, and the like.

The MOSFET 410 is connected to the input terminal of the electronic loader and the output terminal of the current / voltage source in accordance with the polarity (Input1 / Input2), and controls the constant current when controlling the mode input from the key operation unit 100, Adjust. At this time, the resistor R1 located at the source side of the MOSFET 410 is a resistor for stabilizing the current I _d . If the resistor R1 is absent, the voltage supplied to the gate of the MOSFET 410 is V _{gs, and} thus the operation is not stabilized.

The distribution resistor unit 420 conducts current sensing by connecting five resistors R9, R10, R11, R12, and R13 in parallel to the source terminal side of the MOSFET 410, and periodically reads the voltage obtained between the two terminals from the ADC. Informing the microcontroller 200.

The first amplifying circuit unit 430 amplifies and outputs the voltage at both ends of the distribution resistor unit 420 fed back from the MOSFET 410. In other words, the current amount is adjusted to the gate voltage level of the MOSFET 410 to control a constant current, V _gs The level is amplified by the first amplifier circuit section 430 of the voltage across the distribution resistor section 420 and output to the integrating circuit section 450.

The first amplifier circuit portion 430 is composed of a plurality of resistors R39, R84, R85, R93, R94, condenser C15, non-inverting amplifier U21 (used to detect weak signals and having high input impedance), and non-inverting. When the voltage at both ends of the distribution resistor unit 420 is applied to the non-inverting terminal (+) of the amplifier U21, the amplification is applied to the integrating circuit unit 450 to V _d. Output voltage. The amplified at non-inverting amplifier U21 of the first amplifying circuit unit 430, a voltage V _d, but readily available to the formula (V _out = (1 + R1 / R2) V _in) of the non-inverting amplifier, V actual Such _d voltage This doesn't come out. V _d Since the voltage is fed back through the integrating circuit 450 as much as the V _ref voltage supplied to the integrating circuit 450, V _d The voltage at the point maintains V _ref .

The filter 440 is a noise of the voltage between the both ends of the distribution resistor unit 430 amplified by the first amplification circuit unit 430 for current detection based on the voltage between the both ends of the distribution resistor unit 420 in the microcontroller 200. Remove the output to the microcontroller 200.

The integrating circuit unit 450 receives the signal amplified by the first amplifying circuit unit 430 and performs PI control to correct the feedback voltage by the reference voltage V _ref input from the microcontroller 200 (first amplifying circuit unit 430). The signal output from the control unit is equal to the reference voltage V _ref input from the microcontroller 200 and outputs the same. That is, in the integrating circuit part 450, the signal amplified by the first amplifying circuit part 430 corrects the feedback voltage by the setting data. In order to keep the constant current and minimize the deviation from the target value, PI control by feeding back the voltage of the distribution resistor unit 420 amplified by.

The integrating circuit 450 is constituted of a plurality of resistors R81, R83, capacitor C35, an integrator U22, U22-inverting terminal of the integrator (-) amplified in the first amplifying circuit unit 430, a voltage V _d When is applied, PI control is performed to correct the feedback voltage by the reference voltage V _ref of the microcontroller 200 input to the non-inverting terminal (+) of the integrator U22 to output the V _e voltage to the second amplifying circuit unit 460. .

At this time, the voltage V _e output through integrator U22 is expressed as the following equation.

Here, V _int is the initial voltage and can be replaced with V _int = 0.

Therefore V _d Voltage is V _ref Greater than the voltage, the output voltage V _e Will decrease, whereas the voltage V _d will be reduced to V _ref Less than voltage V _e Will increase. While repeatedly feeding back the signal, the voltage of V _e is kept constant and is represented as a graph as shown in FIG. 5.

The second amplifying circuit unit 460 operation amplifies the PI-controlled signal from the integrating circuit unit 450 and the voltage output from the source terminal of the MOSFET 410 and outputs the result to the gate terminal of the MOSFET 410.

At this time, the second amplifying circuit unit 460 is composed of a plurality of resistors R15, R23, R33, R40, and non-inverting amplifier U12, and the source terminal of the MOSFET 410 input to the inverting terminal (-) of the non-inverting amplifier U12. The output voltage and the PI-controlled voltage in the integrating circuit unit 450 applied to the non-inverting terminal (+) of the non-inverting amplifier U12 are amplified and output to the gate terminal of the MOSFET 410. _E V voltage output from the integrating circuit 450 and the voltage V _f voltage distribution voltage by the resistor R15, R23, V _f is a voltage the operational amplifier via a non-inverting amplifier U12 V _gs The voltage controls the gate of the MOSFET 410. And V _g amplified by non-inverting amplifier U12 The voltage is determined by the gain and V _s by Av = 1 + R40 / R33.

Here, the integration circuit portion 450 and the second amplification circuit portion 460 are feedback circuits, and the adjustment of the V _gs voltage is indispensable for internal factors such as external factors such as variation of the voltage / current source, The feedback configuration by the controller is unstable overall and the response time is slow. Of course, it can be overcome to some extent by using a DSP of 100MIPS or more, but due to the increase in unit cost of the product and excessive consumption of components, the design of the feedback circuit of the integrating circuit unit 450 and the second amplifying circuit unit 460 in a hardware configuration. It can be overcome.

The comparator 480 detects whether the voltage deviation of the FET 470 connected between the input terminal Input2 and the distribution resistor unit 420 is reversed in order to protect the circuit device according to the reverse connection. )

In addition, as shown in FIG. 4, the boost voltage supply unit 700 includes an input rectification smoothing circuit unit 710, a switching converter circuit unit 720, an output rectification smoothing circuit unit 730, a feedback control circuit unit 740, and the like. do. In the present invention, mainly manufactured as a product that can be used in low-voltage, high current products of less than 100W class, the forward synchronous rectification method is adopted in proportion to the capacity of the electronic loader.

The input rectification smoothing circuit unit 710 rectifies and smoothes the AC input power to the DC input voltage and outputs the converted converter circuit unit 720.

The switching converter circuit 720 connects the switching IC Q1 to the transformer primary side, and has a Schottky diode D4 having a forward voltage of 0.2 to 0.3 V and a low drain-source resistance (Rds) at turn-on to compensate for power loss. It is composed of forward synchronous rectification method by connecting FETs Q2 and Q3 to the transformer secondary side, and converts the DC input voltage input from the input rectification smoothing circuit unit 710 into the DC output voltage according to the switching control of the switching IC. Output at 730.

At this time, the transformer secondary side rectification of the forward synchronous rectification method uses a fast switching diode, and the diodes used here include a forward and a reflux diode, and mainly a Schottky diode. Since forward voltage of general diode is 0.6 ~ 0.7V and Schottky diode is 0.2 ~ 0.3V, switching converter should use Schottky diode to minimize power loss. However, the higher the current, the greater the power loss. Therefore, to compensate for the diode's power loss, a low Rds FET is used at turn-on to minimize power loss even at higher currents. As a result, a circuit consisting of a forward synchronous rectification converter can be used to reproduce a high-efficiency switching converter, and the circuit package is simplified and a product volume is minimized by using a packaged switching IC to simplify the circuit.

The output rectification smoothing circuit unit 730 smoothes the DC output voltage output from the switching converter circuit unit 720 and supplies it to the electronic loader.

The feedback control circuit unit 740 stabilizes the DC output voltage input from the output rectification smoothing circuit unit 730.

Next, the operation of the fuel cell electronic loader according to the present invention configured as described above will be described in detail with reference to FIG. 7.

7 is a flowchart illustrating an operation process according to the driving of the fuel cell electronic loader according to the present invention.

First, after the user (operator) connects the fuel cell of the performance evaluation target to the fuel cell electronic loader, and operates the power supply on / off key of the fuel cell electronic loader, system initialization is performed (S10) and the microcontroller ( The ADC and the DAC of 200 are initialized (S20).

After the system, ADC, and DAC are initialized, the microcontroller 200 performs constant current (CC), constant voltage (CV), constant resistance (CR), electrostatic force (CP), and dynamic mode (key) from the key operation unit 100 according to a user's operation. It is determined whether the key signal for the performance evaluation of the fuel cell, including the setting of the DYN) and the setting of the maximum value of the current, voltage, and power according to the set mode (S30).

As a result of the determination in step S30, when a key signal for performance evaluation of the fuel cell is input from the key manipulation unit 100, the microcontroller 200 controls the analog board unit 400 to measure the output characteristics of the fuel cell by PI control. In order to receive the voltage and current data through the ADC (S40).

In addition, the microcontroller 200 performs protection functions such as overcurrent (OCP), overvoltage (OVP), overpower (OPP), overheating (OTP), reverse connection (REV), and the like. Perform a communication interface with an external PC connected through (S60).

Thereafter, the microcontroller 200 performs a performance evaluation of the fuel cell according to the constant current CC, the constant voltage CV, the constant resistance CR, the constant power CP, and the dynamic mode DYN. The characteristic data is measured (S70).

Finally, the microcontroller 200 displays the data measured in step S70 through the display unit 500, so that the user can immediately check the characteristics of the fuel cell to be evaluated for performance (S80).

Herein, while the present invention has been described with reference to the preferred embodiments, those skilled in the art will variously modify the present invention without departing from the spirit and scope of the invention as set forth in the claims below. And can be changed.

1 is a block diagram schematically showing the configuration of an electronic loader for a fuel cell according to the present invention;

2 is a block diagram showing in detail the configuration of the analog board of FIG.

3 is a detailed circuit diagram of the analog board unit of FIG. 2;

4 is a detailed circuit diagram of the boost power supply unit of FIG. 1;

5 is a view for explaining the PI control state of the fuel cell electronic loader according to the present invention;

6 is a view showing the external appearance of the front and rear parts of the fuel cell electronic loader according to the present invention;

7 is a flowchart illustrating an operation process according to the driving of the fuel cell electronic loader according to the present invention.

Explanation of symbols on the main parts of the drawings

100: key operation unit

200: microcontroller

300: loader module

400: analog board

500: display unit

600: interface unit

700: boost power supply

Claims (7)

A key operation unit for generating a key signal for evaluating the performance of the fuel cell, including setting of a constant current, a constant voltage, a constant resistance, a constant power, a dynamic mode, and setting a current, voltage, and maximum power value according to the set mode; When the key signal for the performance evaluation of the fuel cell is input from the key operation unit, the control unit controls to measure the output characteristics of the connected fuel cell for PI performance evaluation according to a set mode, and the voltage and current data measured through the PI control. It controls the amount of current and collects the protection and performs the protection function including overcurrent, overvoltage, overpower, overheating and reverse connection, and controls the display of output characteristic information of voltage and current according to the currently set mode measured according to PI control. A microcontroller; A loader module including a field effect transistor, a distribution resistor, a heat sink, and measuring current and voltage of a connected fuel cell for performance evaluation; In order to minimize the deviation of the data measured in the loader module according to the control of the microcontroller, the loader module is controlled by a PI control that feeds back and outputs the measured data from the loader module to be equal to the reference data input from the microcontroller. An analog board unit for controlling and outputting voltage and current data measured by the loader module to the microcontroller according to PI control; A display unit which displays mode setting state information of the electronic loader, a current operation state, and displays voltage and current values measured by the loader module through PI control of the analog board unit according to the control of the microcontroller; Interface unit for inputting key signal for performance evaluation of the PC and fuel cell connected to the outside under the control of the microcontroller, and outputting the voltage and current data measured by the loader module under PI control of the analog board unit. ; And It includes a boost power supply for supplying a voltage for performing performance evaluation of the fuel cell of each cell unit so that the electronic loader can be operated at low voltage at all times. The analog board unit, A metal oxide semiconductor field effect transistor that adjusts the amount of current to a gate voltage level in order to control a constant current when the electronic loader input unit and the output terminal of the current / voltage source are connected in polarity to perform a mode input from the key control unit. oxide semiconductor field effect transistor, MOSFET); A distribution resistor unit connected to the source terminal side of the MOSFET to sense current; A first amplifying circuit unit amplifying and outputting a voltage at both ends of the distribution resistor unit fed back from the MOSFET; A filter for removing noise of a voltage between the both ends of the distribution resistor section amplified by the first amplifier circuit section and outputting the current to the microcontroller for current detection based on the voltage across the distribution resistor section in the microcontroller; An integrating circuit unit for receiving a signal amplified by the first amplifying circuit unit and performing PI control to correct a feedback voltage by a reference voltage input from the microcontroller; And A second amplifying circuit unit which amplifies the PI-controlled signal from the integrating circuit unit and the voltage output from the source terminal of the MOSFET and outputs the result to the gate terminal of the MOSFET; The boost voltage supply unit, An input rectifying smoothing circuit unit rectifying and smoothing the AC input power to a DC input voltage; Schottky diodes with a switching IC connected to the transformer primary and a forward voltage of 0.2V to 0.3V, and field effect transistors (FETs) with low drain-source resistance (Rds) at turn-on to compensate for power loss. A switching converter circuit unit configured to have a forward synchronous rectification method connected to a secondary side of a transformer, and converting a DC input voltage input from the input rectifying smoothing circuit unit into a DC output voltage according to switching control of a switching IC; An output rectifying smoothing circuit unit for smoothing the DC output voltage output from the switching converter circuit unit to the electronic loader; And And a feedback control circuit for stabilizing the DC output voltage input from the output rectifying smoothing circuit. The method of claim 1, wherein the key operation unit, Power supply on / off key; Setting keys for constant current, constant voltage, constant resistance, constant power, and dynamic mode; Remote sensing operation key; Menu keys for setting current, voltage, power maximum values, and sound activation / deactivation functions; A shift key for moving the cursor position left / right; A selection key for activating / deactivating the selected mode; An enter key for storing an input value; And A fuel cell electronic loader comprising a jog dial for adjusting an input value. The method of claim 1, wherein the analog board unit, And a comparator for detecting whether the voltage deviation of the FET connected between the input terminal and the distribution resistor unit is reversed and outputting to the microcontroller for protection of the circuit device according to the reverse connection. Electronic loader. The method of claim 1, wherein the distribution resistor unit, An electronic loader for fuel cells, characterized by connecting five resistors in parallel. The method of claim 1, wherein the first amplifier circuit portion, Consists of multiple resistors, capacitors, non-inverting amplifiers, And a voltage applied at both ends of the distribution resistor unit to the non-inverting terminal of the non-inverting amplifier, amplifies it and outputs it to the integrating circuit unit. The method of claim 1, wherein the integrated circuit unit, Consists of a number of resistors, capacitors and integrators, When the voltage amplified by the first amplifying circuit unit is applied to the inverting terminal of the integrator, a PI control is performed to correct the feedback voltage by the reference voltage of the microcontroller input to the non-inverting terminal of the integrator to the second amplifying circuit unit. An electronic loader for fuel cell, characterized in that output. The method of claim 1, wherein the second amplifying circuit unit, Consists of a number of resistors, non-inverting amplifiers, Amplifying the PI-controlled voltage at the integrating circuit part applied to the non-inverting terminal of the MOSFET and the output voltage of the source terminal of the MOSFET input to the inverting terminal of the non-inverting amplifier to output to the gate terminal of the MOSFET. An electronic loader for a fuel cell, characterized in that.

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