SU1078571A1 - Frequency controller - Google Patents

Abstract

AUTOMATIC FREQUENCY REGULATOR, containing an input generator, a pulley of direct pulses, an oscillator of the reference frequency, a single frequency | ) Ator, the first pulse counter, the input || of the initial installation of which is connected to the output of the input rectangular pulse former through a single-pulse generator, and the counting input - to the output of the first logic element And, the second pulse counter, the counting input of the rotor is connected to the output of the reference pulse generator frequency, and the second logical element, which is such that, in order to increase the accuracy of the controlled frequency, it is equipped with a frequency divider, an AND-NOT logic element, which is connected by its inputs to the outputs of the first Pulse detector, output - to one input of the first logic element And, the other input of which is connected to the output of the pulse generator of the reference frequency through a frequency divider, two inverters, the first of which is connected to the output of the input square pulse former, and the second to the output of the first logic element NAND, reversible pulse counter, second logical element NAND, OR logical element, whose inputs are pairwise combined and connected to the outputs of the reversible pulse counter, logic circuit The comparison is equal to, some of the comparison inputs of which are connected to the outputs of the reversible pulse counter, and others to the outputs of the second pulse counter, the third logical element I, the output of which is connected to the reverse count input of the reverse pulse counter, the input of the direct count And, the second one-shot and the output RS-trigger, the R-input of which is connected to the output of the logic comparison circuit and the S-input to the output of the last bit of the second counter through the second The first input is connected to the output of the first logical element NAND, the second input to the output of the first inverter, the third to the output of the second inverter, and the fourth connected to the fourth input, the house of the third logical element I, n the third input of which is connected to the input of the second inverter, the second input to the input of the first inverter, and the first input to the output of the logic element; and OR, and the combined fourth inputs of the first and second logic elements AND are connected either to the output of the reference frequency pulse generator via the additionally introduced frequency divider, or to one of the bit outputs. second pulse counter.

Description

The invention relates to electrical engineering, in particular, to automatic control of the frequency generated by an alternating alternating voltage unit on a yarn, and can be used to automatically control the frequency of autonomous power supply sources. Digital automatic frequency controllers are known that have sufficiently high frequency control accuracy by using the aesthetic frequency control principle {| l. However, these devices use an integrating electromechanical actuator, namely an electric motor, to obtain the astatic frequency control principle. The use of an electric motor imposes considerable limitations on the speed of frequency control. In addition, such a frequency control system is complex, since it usually requires, in addition to the electric motor itself, a whole range of mechanical elements (gearbox, system, drum, etc.) to affect the fuel supply system, which significantly reduces the system’s negligence and limits the scope the use of such devices due to complexity and bulkiness. A frequency regulator is known, allowing for the use of simpler and more high-speed electromechanical devices, such as traction electromagnets 2, as executive elements. However, the accuracy of maintaining a given frequency value for these regulators depends on a variety of external factors, such as load magnitude, winding temperature and environment, etc. The closest to the proposed technical entity is a frequency controller containing an input shaper of square pulses, a reference frequency generator, two AND gates, two pulse counters, a one-shot, a parallel synchronous register, and a scaling factor control block, with etrm the initial setup input of the first the pulse counter is connected to the output of the input shaper of rectangular pulses via a one-shot, and the counting input is connected to the output of the first logic element And, the counting input of the second th pulse counter connected to the output of the reference oscillator frequency of the pulses. The known device determines the deviation of the specified value of the period of the generation voltage from the actual and, depending on the value of it from | It forms high-frequency pulse pulses with a ratio that is proportional to the magnitude of the deviation. In this case, a definite deviation value corresponds to a strictly defined duty cycle. By principle, this frequency control is static, i.e. the magnitude (duty cycle) of the control signal is strictly proportional to the deviation. At the same time, a change in the electromagnet force due to the temperature maintenance of the parameters of the electromagnet elements (coil resistance, spring stiffness, etc.), fluctuations in the voltage of the electromagnet supply voltage, displacement of the electromagnet position from the optimal setting and change in the parameters of the engine fuel supply system frequency control error. The accuracy of maintaining a given frequency depends also in this case on the magnitude of the load, since for each particular amount of load, to obtain a given frequency, the measles of the electromagnet must occupy the position corresponding to that particular load, while the position of the electromagnet (control signal) is proportional to magnitude of frequency deviation. The purpose of the invention is to improve the frequency control accuracy by eliminating the influence on the accuracy of maintaining a given frequency of external factors (load, temperature drift of the parameters of the actuator, changing the parameters of the fuel supply system, temperature influence, etc.). The goal is achieved by the fact that an automatic frequency controller containing an input shaper of rectangular pulses, a generator of pulses of a reference frequency, a single vibrator, the first pulse counter, the input of the initial installation of which is connected to the output of an input shaper of rectangular pulses through a single vibrator, and the counting input to the output of the first the logic element And, the second pulse counter, the counting input of which is connected to the output of the pulse generator of the reference frequency, and the second logic element And, equipped with a frequency divider, an NAND logic element that is connected by its inputs to the outputs of the first pulse counter, and an output to one input of the first I logic element, the other input of which is connected to the output of the reference frequency generator through a frequency divider, two inverters, the first of which connected to the output of the rectangular impulse input driver, and the second to the output of the first NAND logic element, reversible pulse counter, the second NAND logic element, the OR logic element, the inputs to The pairs are combined in pairs and connected to the outputs of the reversible pulse counter, the comparison logic is equal, one comparison inputs of which are connected to the outputs of the reverse pulse counter, and others to the outputs of the second pulse counter, the third logical element I, the output of which is connected to the reverse count input of the reverse pulse counter, the input of which is connected to the output of the second. And, the second one-shot and output RS-trigger, the R-input of which is connected to the output of the comparison logic circuit is equal to, and the input is to the output of the last bit of the second counter through the second one-shot; connected to the output of the first NAND logic element, the second input to the output of the first inverter, the third to the output of the second inverter, and the fourth connected to the fourth input of the third logical element And, the third input of which is connected to the input of the second inverter, The first input is with the input of the first inverter, and the first input is with the output of the OR logic element, the combined fourth inputs of the first and second logic elements AND are connected either to the output of the reference frequency pulse generator through the additionally entered frequency divider or one of the output bits second pulse counter. The frequency regulator generates a variable output signal (controlling the actuating electromagnet), which changes in the appropriate direction until the executive element changes the position of its operating part so that the frequency deviation becomes zero. Figure 1 shows the block diagram of the device; Figures 2 and 3 show time diagrams explaining the principle of operation of the device. The device contains an input shaper 1 of rectangular pulses that converts a sinusoidal input voltage generated by the control object into rectangular pulses of a period (or half-period) duration, a generator of 2 pulses of the reference frequency, two counters 3 and 4 pulses of the direct counting, the first of which has an input of the initial NU setting, a reversible counter of 5 pulses with a 4-T direct count input and a reverse T, an output RS-trigger b,. two single vibrators 7 and 8, frequency divider 9, two inverters 10 and 11, three logic elements and 12-14, two logical elements AND-NOT 15 and 16, logical element OR 17, comparison logic 18 by equal. The output of the RS-flip-flop 6 through the amplifier is connected to the actuator (electromagnet), which regulates the flow of fuel. In this case, the fourth inputs of the And 14 and 13 elements are interconnected and connected to one of the outputs of the Q bits of the counter 4, in another embodiment of this part of the controller, the fourth inputs of the And 14 and 13 elements connected together are connected to the output of the generator 2. Regulator frequency works as follows. The electrical unit generates a voltage at a frequency f (period T l / f), which is converted by the shaper 1 through the transition of a sinusoid through a zero value into rectangular pulses of duration T / 2. When the former is formed as a trigger for a square pulse with a duration T and a period of 2T (Fig. 2), in the latter case, pulses with a duration T / 2 and a period T are first formed and then split into two with a trigger, resulting in a trigger generator forming pulses of duration T and a period of 2 T. On the front (front) of the pulses from the output of the imaging unit 1, the single vibrator 7 forms a short pulse that sets the counter 3 to the initial state at its input NU. By the number of pulses t from the generator 2 of the reference frequency arriving at the counting input T through the divider 9 and the logic element 12, the counter 3 counts from the initial state (zero) the number and the pulse corresponding to the period T of the given frequency f ,. When the counter 3 reaches the specified number of pulses, the signal at the output of the element 12 passes from the state of a logical unit to a logical zero, thus forming a pulse T. To do this, only the outputs of the counter 3 are connected to the inputs of the element 15, which take the state of a logical one at the achievement of a given number of the corresponding T, after which the arrival of the counting pulses t2 on the counter 3 is prohibited by the logic element And 12. The elements And 13 and 14 are made using the inverTcSpoB 10 and 11 the interval of deviation T from Td taking into account the sign deviations, ie element And 14 selects the interval Ci T - at T T, t, and the element And 13 interval 2 T ,.- T at. During the intervals t, the + t input of the reversible counter 5 receives counting pulses tj, where t is the period of the pulses received, obtained by dividing the additional counter 19 or the counter 4 pulses with the following period t, generated by the generator 2, and during the interval 1 - by - T is the input of counter 5. Thus, if there is a deviation of d T T - Td, counting pulses are received at the corresponding deviation sign of dT input + T or -T of counter 5. As a result, with one DT sign, the state of counter 5 increases with speed, P is the reference value of dT and the division factor of divider 19 (or used output of counter 4) and frequency of generator 2. At opposite sign of deviation DT of counter, state 5 is similarly reduced are being done. An increase or decrease in the state of the counter occurs until the situation occurs, when DT is 0, or until counter 5 reaches one of its limiting states, maximum or minimum (for example, all 4 turns of counter 5 in unit state and all inputs are in the zero state. When the maximum state is reached (all inputs are in the single state) of the counter 5, the IS-NOT element 16 outputs the logical zero level, thus prohibiting the passage of counting pulses that increase the state of the counter 5 through the And 14 element. The minimum state (all outputs or part of them in zero states) of counter 5eLement OR 17 gives a logic level of zero, thus prohibiting the passage of counter-decreasing state 5 counting pulses through elements 13, Elements 4,6,8 and 18 perform the function of obtaining at the output of pulses a sufficiently high tracking frequency (for example, 300-500 Hz) with a constant tracking period and pulse duration proportional to the state of the outputs of the accumulating counter 4. For this, the pulses from the generator 2 are divided into getting ass constant repetition rate (Figure 3), such as 300500 Hz. On the leading edge of the received pulses, the one-shot 8 generates short pulses that set the RS flip-flop 6 into a single state. Counter 4 counts the counting pulses, and at the moment when the output states of counter 4 completely coincide with the state of the outputs of the reversible counter 5, the comparison circuit 18 generates a pulse that sets the RS-trigger b to the zero state, in a forward way A pulse is generated whose duration is proportional to the state of counter 5, and the higher the number of counter 5 states, the longer the received pulse, and at the maximum state of counter 5 this pulse turns into an this level is a logical unit, and at the minimum constant level of logic zero. When using the inverse output, the dependence is inversely proportional. The signal from the output of the trigger 6 is fed through an amplifier to the executive electromagnet. Thus, if there is a deviation AT of the same sign (positive), counter 5 increases its state, respectively, the pulse duration at the output of trigger b increases (and when using the inverse output of trigger b, the pulse duration decreases, the force decreases), as a result, the fuel delivery system increases the fuel supply The frequency increases, the magnitude of the period T decreases. This happens until the DT deviation is completely worked out to zero, that is, f fqt becomes. If there is a deviation dT of another sign (negative), the counter 5 similarly reduces its state by reducing the pulse duration at the direct output of the trigger 19 (increasing the pulse duration at the inverse output) and thereby changing the electromagnet force in such a way as to reduce the frequency f to until T, e, f T O, becomes T T Thus, the device ensures that the deviation of the generated frequency from the specified value is tested until this deviation vanishes. In this case, only one information signal is used - the frequency. Accordingly, since the testing of frequency deviation is carried out to zero and only one parameter is used as input information - frequency, influence of external factors, such as load, electromagnet setting accuracy, change in parameters of fuel supply system, electromagnet coil supply voltage, temperature maintenance The adjustment elements of the CHCTeNM cannot change the accuracy of deviation testing. The accuracy of frequency deviation testing by the frequency regulator is determined only by the frequency stability of generator 2, which is easy to provide when using a generator with quartz frequency stabilization, as well as frequency measurement resolution and output frequency variation, which can be set by any choice of the corresponding counter capacities and frequency generator 2. The force of the electromagnet varies to

as long as the deviation is not worked out to zero. Moreover, the deviation testing rate is proportional to the deviation value and is determined by the frequency of the generator of reference pulses 2, the division factor of the additional divider (or the corresponding output of the counter 4) and the capacity of the reversing counter 5 can be set within very wide limits (almost from the duration of one period to infinity). Therefore, the regulator allows to ensure the stability of the regulation and the high quality of transients without laborious operations on the precise installation of the actuating element. The accuracy of testing from the refining is determined only by the t6 accuracy of the 5 deviation measurement, i.e. is set by the frequency of the reference pulse generator 2, the division factor of the divider 9 and the capacity of the counter 3, and can be as high as desired.

The proposed device allows implementation on ready-made functional elements of integrated circuits.

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Claims (1)

(54) AUTOMATIC FREQUENCY REGULATOR, comprising an input rectangular-pulse shaper, a reference frequency pulse generator, a single-shot, a first pulse counter, the initial setting of which is connected to the output of a square-wave input shaper through a single-shot, and a counted input - to the output of the logic gate I, the second pulse counter, the counting input of which is connected to the output of the pulse generator of the reference frequency, and the fourth logical element And, characterized in that, in order to improve accuracy frequency control, it is equipped with a Frequency divider, an AND gate, which is connected by its inputs to the outputs of the first pulse counter, and an output - to one input of the first logic gate And, the other input of which is connected to the output of the pulse generator of the reference frequency through the frequency divider, two inverters, the first of which is connected to the output of the input shaper of rectangular pulses, and the second to the output of the first logical element AND NOT, a reversible pulse counter, the second logical element AND NOT, a logical OR element, the inputs of which are paired and connected to the outputs of a reversible pulse counter, the logic of comparison is equal, some comparison inputs of which are connected to the outputs of a reverse pulse counter, and others to the outputs of the second pulse counter, the third logical element And, the output of which is connected to the reverse counting input of a reversible pulse counter, the direct counting input of which is connected to the output of the second logical element AND, by the second one-shot and output | Г RS-flip-flop, whose R-input is single-keys P ¹ to the output of the logical comparison circuit for the same, and S-input - to You are a | during the last discharge of the second counter-g chip through the second one-shot, while * the first input of the second logical element AND is connected to the output of the first logical element Y-NOT, the second input is to the output of the first inverter, the third to the output of the second inverter, and the fourth is connected to fourth in, the house of the third logical element And, the third input of which is connected to the input of the second inverter, the second input with the input of the first inverter, and the first input with the output of the logical element; that OR, and the combined fourth inputs of the first and second logic elements are connected either to the output of the pulse generator of the reference frequency through an additionally entered frequency divider, or to one of the discharge outputs of the second Pulse Counter.