KR100448720B1 - Eddy Current Exciter Controller - Google Patents

Abstract

The present invention operates the digital input and output signal processing by setting the software, the signal processing with the peripheral device through the RS-232 communication port, and by separating the control algorithm into a plurality of data processing modules to process The present invention relates to an iscile exciter controller for increasing stability and precision. The present invention calculates a difference between a desired setting value and a speed or torque input value actually measured by a program recorded in a flash memory of an intelligent CPU. The output is adjusted according to the software program function of the controller determined by the magnitude of the deviation. Here, the operation characteristics and functions of the CPU used inside the controller can be easily changed by simply changing the program according to the purpose, and the operation status of the CPU and the contents of the processed data can be changed using the RS-232 communication port. The information is transmitted to the peripheral device so as to obtain the processed data in real time by combining the ease of use of the self-diagnostic function of the controller with the data acquisition device if necessary.

In addition, control algorithms and data processing routines are stored in flash memory to improve product performance, minimize instability, and are designed with the most basic components to realize small, large-capacity controllers, and to minimize problems. It will greatly improve.

Description

Eddy Current Exciter Controller

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an Eddy Current Exciter Controller, and in particular, to operate digital input and output signal processing by software setting, and to perform signal processing with a peripheral device through an RS-232 communication port. In addition, the present invention relates to an iscici controller for improving stability and precision by dividing a control algorithm into multiple data processing modules.

Usually, the dynamometer E is roughly classified into an alternating current (AC) dynamometer, a direct current (DC) dynamometer, and an eddy current (EC) dynamometer according to the difference in the type of the current supply and the dynamometer which changes the magnitude of the electromotive force generated in the rotor.

On the other hand, the dynamometer controller is applied to various applications, such as the engine dynamometer for engine performance and durability test or the performance of a real vehicle, the vehicle dynamometer for exhaust gas measurement generated when driving the vehicle, depending on the configuration of the drive device.

As is well known, the dynamometer controller sets the operating mode of the dynamometer, converts a desired physical quantity into a signal corresponding to the controller, and controls the current supplied to the final dynamometer. The maximum current capacity and current control according to the capacity of the dynamometer The accuracy of the product and the durability of driving according to the surrounding environment were the criteria for product evaluation.

In particular, the precision of current control is becoming more important due to the complexity of the operation mode. Also, as the type and amount of data required to verify the evaluation items for improving the performance of the EUT increase, the peripheral device and the signal processing are increased. Increasing efficiency is an important factor in controller performance because AC interface is converted into DC current.

On the other hand, the conventional EC exciter controller uses a passive analog control element as a signal processing and a control unit as a core, and thus has a disadvantage of complicated hardware configuration and low operation efficiency.

In addition, since the output is generated by a simple comparison difference, it is impossible to proactively cope with complex test modes, and due to the use of simple relays for signal processing with peripheral devices, durability due to long-term use decreases, and problems are identified even when a failure occurs. And a problem that takes a lot of time, such as repair.

Therefore, the present invention has been proposed to solve various problems occurring in the conventional EC exciter controller as described above.

An object of the present invention is to operate the digital input and output signal processing by the setting of the software, to perform signal processing with the peripheral device through the RS-232 communication port, and to divide the control algorithm into a plurality of data processing modules It is to provide an isci exciter controller which can improve the stability and precision by processing.

"Ish exciter controller" according to the present invention for achieving the above object,

The program recorded in the flash memory of the intelligent CPU calculates the difference between the desired setting value and the actual measured speed or torque input value, and adjusts the output according to the software program function of the controller determined according to the magnitude of the deviation. Here, the operation characteristics and functions of the CPU used inside the controller can be easily changed by simply changing the program according to the purpose, and the operation status of the CPU and the contents of the processed data can be changed using the RS-232 communication port. The information is transmitted to the peripheral device so as to obtain the processed data in real time by combining the ease of use of the self-diagnostic function of the controller with the data acquisition device if necessary.

In addition, control algorithms and data processing routines are stored in flash memory to improve product performance and minimize instability.

Also, general controller is composed of control module, drive module, power module, filter module, and other protection devices to minimize electrical noise or interference generated from power control module. The hardware configuration is complicated, and production and maintenance are difficult, but the controller according to the present invention is designed as the most basic component to realize a small-capacity controller, and greatly improves the stability of the product by minimizing the problem occurrence factor. .

1 is an exemplary view of applying the exciter controller according to the present invention;

Figure 2 is a block diagram showing the configuration of the exciter controller according to the present invention,

3 is a configuration diagram of an embodiment of a control unit of FIG. 2;

4 is a diagram illustrating an embodiment of a gate signal output unit of FIG. 2;

5 is a configuration diagram of an embodiment of the current sensor unit of FIG. 2;

6 is a configuration diagram of an embodiment of the rotational speed input unit of FIG. 2;

7 is a configuration diagram of an embodiment of the torque input unit of FIG. 2;

8 is a configuration diagram of an embodiment of an AC power input unit of FIG. 2;

9 is a view for explaining the software ranking in the present invention,

FIG. 10 is a configuration diagram of an embodiment of a digital phase controller of FIG. 2;

FIG. 11 is a diagram illustrating an embodiment of the current controller of FIG. 2.

<Explanation of symbols for the main parts of the drawings>

100: engine

300: EC exciter controller

500: data collection and system control

400: EC dynamometer

710: control unit

711: current sensor unit

712: AC power input unit

716: torque input unit

717 rotation speed input unit

718: gate signal output unit

Hereinafter, described in detail with reference to the accompanying drawings, preferred embodiments of the present invention according to the technical spirit as described above.

The vortex exciter controller according to the present invention arbitrarily sets an operation mode such as rotational speed, torque, or actual vehicle simulation in order to test the performance and durability of various engines, real vehicles, and other driving devices. It is used to absorb or control the torque generated from the driving source of the test apparatus or to control the driving speed of the driving apparatus.

DC current is controlled and supplied to the dynamometer winding according to the set operation mode and physical quantity. At this time, a vortex is generated in the rotor plate according to the amount of current supplied, and an electromotive force is generated by the size of the vortex, and the magnitude of the electromotive force is proportional to the square of the amount of current. By using this, the operating mode and physical quantity of the driving source can be efficiently controlled by using a dynamometer.

1 is an exemplary view showing a configuration of a system to which an EC exciter controller according to the present invention is applied.

The power generated by the internal combustion engine 100 using diesel or gasoline as fuel is converted into a rotational speed and torque of the engine power shaft corresponding to a change in the mixing ratio of fuel and air supplied according to the opening degree of the throttle valve 200.

At this time, the EC exciter controller 300 adjusts the electromotive force generated by adjusting the amount of current supplied to the winding of the EC dynamometer 400 in order to maintain a constant number of revolutions of the engine based on the determined opening of the throttle valve 200. Change.

For example, as the engine speed increases, the value measured by the rotation speed measurement sensor installed in the dynamometer shaft increases, and the EC exciter controller 300 collects the data and the rotation speed set by the system controller 500 increases and increases the rotation. By calculating the deviation of the number to increase the current supplied to the winding of the EC dynamometer 400 increases the load of the engine, thereby reducing the number of revolutions of the engine by the increased load.

On the contrary, when the engine speed decreases, the current supplied to the dynamometer winding is reduced to reduce the load of the engine. At this time, the engine speed increases by the reduced load.

In addition, the EC exciter controller 300 adjusts the amount of current supplied to the winding of the EC dynamometer 400 in order to maintain a constant torque of the engine 100 based on the determined opening degree of the throttle valve 200. Change the electromotive force. As the output of the engine increases, the value measured by the torque measurement sensor installed in the dynamometer enclosure increases, and the EC exciter controller 300 calculates the deviation between the torque set by the data collection and the system controller 500 and the increased torque, and then the EC. By reducing the current supplied to the winding of the dynamometer 400 reduces the load of the engine, thereby reducing the output of the engine by the reduced load. At this time, the number of revolutions of the engine increases due to a decrease in the load absorbed by the EC dynamometer 400 at a relatively same output. On the contrary, when the output of the engine decreases, the current supplied to the dynamometer winding increases to increase the load of the engine, and the output of the engine increases by the increased load.

In FIG. 1, reference numeral 600 denotes a vehicle driving roller.

2 is a block diagram showing the configuration of an EC exciter controller according to the present invention.

The power can be supplied in either 220V single or three phases, depending on the wiring method.

The input filter 702 applies electrical noise generated by the operation of the SCR 703 to the power supply when the input power passes through the protective fuse or the circuit breaker 701 and passes through the SCR 703 operated by the gate signal. Block it from becoming

In addition, the output filter 704 improves the characteristics of the EC dynamometer 400 by mitigating a rectangular waveform generated at the output of the SCR 703 that controls the amount of current by changing the direct current into alternating current.

The control unit 710 receives the signals output from the stabilization element and the converter element, calculates the deviation of the torque in software and performs control by the difference, thereby maintaining the torque at all times, thereby improving precision and accuracy.

The control unit 710 is provided with a current sensor unit 711 for measuring the amount of direct current supplied to the dynamometer using the Hall effect.

In addition, the AC power input unit 712 for sensing the phase of the power supply and AC power required for the motherboard is implemented, and there is an RS-232 communication port 713 for transmitting internal operation data and external commands with a peripheral device.

In addition, the digital input port 714 for improving the stability of the function of the controller even in the event of communication failure, and for setting basic operating conditions and maintaining smooth control, and a digital output port 715 for displaying operation status and interface with external devices. have.

The digital input port 714 may be connected to a photo coupler 707 or a digital output of an external device, and the digital output port 715 may be connected to a photo transistor 708 or a digital input of an external device. The torque input unit 716 is provided to detect a state of torque generated from the dynamometer 400, which is connected to the load cell 705. There is also a rotation speed input unit 717 for measuring the rotation speed of the dynamometer 400, which is connected to the encoder 706 (or pulse pickup).

In addition, a gate signal output unit 718 for controlling the SCR 703 is provided, and a digital phase controller 719 is provided for SCR firing in synchronization with the power frequency, and the current control data is processed. There is provided a current controller 720 for.

In the conventional controller, in order to measure torque and rotational speed, the low mv signal generated in a separate load cell is amplified to several Volt, and a separate module for signal and a sensor for measuring the rotational speed are applied to apply an excitation voltage to the load cell. Although it is equipped with a separate module for converting the frequency into a voltage of several Volt, in the present invention, instead of using a separate module, the signal is input using a stabilizing element and a converter element, and software control is performed for precision. And accuracy.

3 is a diagram illustrating an embodiment of the controller.

It features high-level features, including 130 instructions executed on a single clock, 32 * 8 general-purpose registers, and 8MIPS at 8MHz clock. There is flash memory for program and data memory inside. There are also three channels of timers / counters, three channels of PWM (pulse width modulation), eight channels of 10-bit analog-to-digital converters, programmable serial UARTs, and 32 channels of programmable ports (714, 715). , 717, 718).

The port 714 has a digital input unit for setting the operating mode of the EC exciter controller externally and a current amount signal input unit 714-1 supplied to the dynamometer, and is isolated from the external power source using the photo coupler 707. .

The port 717 has an analog signal output unit and a rotation speed measurement signal input unit 717-1 for interfacing the operating state of the controller with the outside.

The analog signal output unit generates a 0 to 10V DC by using a 12-bit analog-to-digital converter 717-2.

The port 718 has a gate operation signal output port 718-1 for driving the SCR 703 for converting AC power into DC current, and input ports 718-2 and 718-3 for measuring rotation direction and power phase. There is).

The port 715 has a programmable serial RS-232 communication input / output unit, a digital output unit for interfacing the operating state of the controller to the outside, a setting signal input unit for user use, and a signal input unit 715-1 for receiving torque of a dynamometer. There is. The digital output unit uses a separate driver 715-2 to obtain sufficient output to drive the relay, and is also isolated from an external power supply using the photo transistor 708. The RS-232 signal amplifies the signal by using the transistor 715-3 to reduce the influence of electrical noise. The setting signal input unit converts a 0 to 10V DC signal into a frequency and passes through the frequency converter 715-4.

4 is a diagram illustrating an exemplary configuration of the gate signal output unit 718.

The high voltage / current Darlington driver 721 amplifies the weak gate signal for controlling the SCR 703, and the choke coil 722 uses the interference and noise of the SCR gate signal amplified by the high voltage / current Darlington driver 721. Filter by high quality signal with reduced.

5 is a diagram illustrating an embodiment of the current sensor unit 711.

The current sensor 731 measures the amount of DC current supplied to the dynamometer using the Hall effect, and differentially amplifies the measured value in the differential amplifier 732 to obtain a current feedback signal.

6 is a diagram illustrating an embodiment of the rotation speed input unit 717.

The voltage stabilizer 741 stabilizes the pulse signal generated by the encoder 706, and processes the stabilized signal as a rotation speed measurement signal by the differential line receiver 742.

7 is a diagram illustrating an embodiment of the torque input unit.

In order to stably supply the excitation voltage supplied to the load cell 705 to measure the torque generated by the dynamometer, the excitation voltage is stabilized using a voltage stabilizer, and a sufficient driving current is made through the current driver to the load cell 705. Supply it.

The dynamometer generates a force in the same direction as the rotational direction, and this force causes a strain in the strain gauge inside the load cell 705. At this time, the electrical resistance in proportion to the amount of deformation is changed, so that the bridge of the electrical equilibrium state is changed. An imbalance occurs in the circuit, which increases the accuracy of the drift signal generated by a stabilized supply of power.

The differential amplifier 751 differentially amplifies the generated bridge signal, and the CMOS timer 752 generates a pulse signal proportional to the magnitude of the differentially amplified signal and outputs it as a torque feedback signal.

8 is a diagram illustrating an embodiment of the AC power input unit 712.

After the voltage is dropped by the transformer 761 in order to convert the input power to control, the AC is converted into DC using the bridge element 762. Since the converted DC power includes an AC component, a voltage stabilizer 763 is used to generate a complete DC power.

In addition, in order to efficiently control the SCR, it is necessary to detect the zero point alternation of each phase. For this purpose, the phase detector 764 accurately detects the phase and outputs the detected phase signal.

The software in the present invention runs on an Atmel Atmega163 processor operating at an 8 MHz clock frequency. Each function is divided into four data processing steps, and processing is performed according to the processing load of the final CPU and the data processing step determined at 10KHz, 360Hz, and 120Hz as shown in FIG. 9 according to the interrupt priority according to the purpose and precision of each function. Are divided into subprocessing steps.

10KHz data processing is the fastest processing routine that processes every 100 microseconds, and basically performs phase control with several data acquisition functions. At the start of the data processing, 120Hz and 360Hz data processing is performed after receiving data converted from three rotational speeds, torques, and user setting values into frequency values. Once this is done, it is executed in assembly language to operate the remaining functions with optimum efficiency.

All implementations based on system functionality and user configuration take place here. It is an external controller that performs a multifunction such as amplification coefficient, feedback, or setting value which is actively stored or changed in memory. Another important feature is the description of cabin driving or analog input and output signal processing. Since this data processing is a low speed of 120 Hz, a program is written in the "C" language to improve the operation efficiency. The initial stages of this section collect and process torque, speed, and user input. The torque signal is used as a control value by changing the load cell signal of 30mv in the CMOS timer to a frequency value of 33KHz. Next, the rotational speed measurement measures and calculates the period of the pulse input from the processor and is used to control the rotational speed input value.

Another function is a simple real vehicle model function that calculates vehicle resistance as a quadratic function and the electrical inertia value added by multiplying the acceleration by the vehicle weight to be described. The result of both functions is the force (F), and the sum of the two forces is used as the set point of the other controller when running a real vehicle load. Another function required to describe a real vehicle load is to calculate the resistance that occurs as the vehicle progresses. It calculates the total resistance applied to the entire vehicle, such as the vehicle weight, vehicle rolling resistance, and wind loss proportional to the square of the vehicle speed, depending on the angle of climb, so that the corresponding dynamometer is absorbed by the dynamometer It is. Another important feature is the ability to customize the units of torque, speed and current values used in controllers and data analyzers.

FIG. 10 is a diagram illustrating a configuration of an embodiment of the digital phase controller 719.

When the compensated phase value is input, the output value of the loop filter 775 and the adder 771 are added to set the frequency value of the numerically controlled oscillator (NCO) 772. The digital phase control loop replaces conventional voltage controlled oscillators. The digital phase control loop has a specific sensitivity depending on the 60Hz input supply frequency, which is set to the sum of the loop filter's output and the compensation value. The software assumes that the center frequency of the digital phase control loop is always a fixed value, but the actual center frequency is determined by a specific parameter integer. The output of the digital phase control loop is input to the gate energization sequential generator 773, which is triggered six times per cycle of the input power source and determines which combination of SCRs are energized. There are three possible energization patterns and initialization settings as determined by the software. This is three phase forward rotation, three phase reverse rotation, and single phase operation. The gate energization sequential generator 773 provides a feedback signal to the phase detector 774 and effectively divides the output of the digital phase control loop by six. The phase detector receives the satellite set value after the transformer output stage of the power supply. The output of the phase detector 774 is passed to a loop filter 775 that gently processes the square waveform. When the phase control process is completed, the SCR output current is detected at the analog input.

11 is a diagram illustrating an embodiment of the current controller.

The 360 Hz data processing step performs internal current control. The 10KHz data processing is processed once every 28 runs and the actual operation is processed at 357Hz. The control is a simple proportional controller 783 including a feed forward function 781. This was chosen for several reasons. The first occurrence of the deviation is a variable that can be minimized over time with high control sensitivity, and can be handled only with proportional control. Second, even a slight deviation is not a critical control function that does not significantly affect the overall performance. Third, the feed forward function allows for easy minimization of deviations even with certain large load changes.

The first adder 782 adds the current set value and the current feedback value converted into the digital frequency value and outputs the difference. The analog feedback voltage applied here is intentionally set slightly higher than the zero level for automatic zero adjustment by software, because the analog-to-digital converter cannot convert negative voltages. During the 0.5 second time delay when the system is initialized, the SCR energization and current control are performed to control the output current to zero, and then the difference with the current input is stored as a parameter for future compensation of the current controller. The second adder 784 adds the output of the feed forward function 781 and the output of the proportional controller 783 to output the deviation, and the generated deviation satisfies the effective control range, and the digital phase control loop. The range limiter 785 is passed to prevent overflow from occurring. This deviation value is passed through a phase range limiter 786 to a phase compensation filter 787 to compensate for the limited frequency response of the phase controller. The final phase compensation value is stored as a parameter and used for phase control.

According to the present invention described above, the difference between the desired setting value and the actual measured speed or torque input value is calculated by the program recorded in the flash memory of the intelligent CPU, and is output to the software program function of the controller determined according to the magnitude of the deviation. There is an advantage that can be adjusted automatically.

In addition, the operating characteristics and functions of the CPU used inside the controller can be easily changed by simply changing the program according to the purpose.The operating status of the CPU and the contents of the processed data can be changed using the RS-232 communication port. By transmitting the operation information to the peripheral device, there is an advantage in that the self-diagnostic function of the controller and in combination with the data acquisition device if necessary to obtain the processed data in real time.

In addition, by storing and processing control algorithms and data processing routines in flash memory, it is possible to improve product performance and minimize instability.

Also, general controller is composed of control module, drive module, power module, filter module, and other protection devices to minimize electrical noise or interference generated from power control module. The hardware configuration is complicated, and production and maintenance are difficult, but the controller according to the present invention is designed as the most basic component to realize a small-capacity controller, and greatly improves the stability of the product by minimizing the problem occurrence factor. There is an advantage.

Claims (8)

delete In EC exciter controller, An input filter for filtering electrical power through the protective fuse or the circuit breaker to remove electrical noise; An SCR for converting alternating current into direct current and controlling the amount of converted direct current; An output filter for filtering the square waveform generated at the output of the SCR to relax the square waveform; The current sensor unit measures the amount of DC current supplied to the dynamometer using the Hall effect to calculate the deviation of the torque and to control the difference as much as possible to keep the torque constant. AC power input for supplying AC power to detect the phase of power, RS-232 communication port for transmitting peripheral operation and internal operation data and receiving external command, and improve the stability of controller function even in case of communication failure. Digital input port for setting basic operating conditions and maintaining smooth control, Digital output port for operating status display and external device interface, Torque input for detecting torque generated from dynamometer, Rotation of dynamometer Rotation speed input unit for measuring the number and gate scene for controlling the SCR And a controller comprising a gate signal output unit for outputting a call, a digital phase controller for SCR firing synchronized with a power frequency, and a current controller for processing current data sensed by the current sensor unit. Exciter controller. The method of claim 2, wherein the gate signal output unit, A high voltage / current darlington driver for amplifying the weak gate signal for controlling the SCR; And a choke coil configured to filter the SCR gate signal amplified by the high voltage / current Darlington driver and output a high quality signal with reduced interference and noise. The method of claim 2, wherein the current sensor unit, A current sensor for measuring the amount of direct current supplied to the dynamometer using the Hall effect; And a differential amplifier configured to differentially amplify the value measured by the current sensor and output a current feedback signal. The method of claim 2, wherein the rotation speed input unit, A voltage stabilizer for stabilizing the pulse signal generated by the encoder; And a differential line receiver configured to process the stabilized signal as a rotation speed measurement signal and output the processed signal. The method of claim 2, wherein the torque input unit, A differential amplifier for differentially amplifying the bridge signal output from the load cell; And a CMOS timer generating a pulse signal proportional to the magnitude of the differentially amplified signal and outputting the pulse signal as a torque feedback signal. The digital phase controller of claim 2, A summer for summing the compensated phase value and the output value of the loop filter at the next stage; A numerically controlled oscillator for outputting a frequency corresponding to the output value of the summer; A gate energizing sequential control generator triggered six times per cycle of the input power source and determining which combination of SCRs to energize; A phase detector for detecting a phase in an output signal of the gate energization sequential control generator; And a loop filter for smoothly processing the square waveform output from the phase detector. The method of claim 2, wherein the current control unit, A feed forward function unit configured to process an input current setting value as a feed forward function; A first adder for adding the current set value and the current feedback value converted into the digital frequency value and outputting the difference; A proportional controller configured to proportionally control an output signal of the first adder; A second adder configured to add an output of the feed forward function unit and an output of a proportional controller to output a deviation; A range limiter for limiting a range of the generated deviation; A phase range limiter for phase-limiting the output signal of the range limiter; And a phase compensation filter for filtering the output signal of the phase range limiter to compensate for the limited frequency response of the phase controller.