CN109660209B - Rotary transformer signal modulation circuit and motor driving system - Google Patents
Rotary transformer signal modulation circuit and motor driving system Download PDFInfo
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- CN109660209B CN109660209B CN201910023859.7A CN201910023859A CN109660209B CN 109660209 B CN109660209 B CN 109660209B CN 201910023859 A CN201910023859 A CN 201910023859A CN 109660209 B CN109660209 B CN 109660209B
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- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03C—MODULATION
- H03C1/00—Amplitude modulation
- H03C1/36—Amplitude modulation by means of semiconductor device having at least three electrodes
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03C—MODULATION
- H03C1/00—Amplitude modulation
- H03C1/08—Amplitude modulation by means of variable impedance element
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03G—CONTROL OF AMPLIFICATION
- H03G1/00—Details of arrangements for controlling amplification
- H03G1/0005—Circuits characterised by the type of controlling devices operated by a controlling current or voltage signal
- H03G1/0017—Circuits characterised by the type of controlling devices operated by a controlling current or voltage signal the device being at least one of the amplifying solid state elements of the amplifier
- H03G1/0029—Circuits characterised by the type of controlling devices operated by a controlling current or voltage signal the device being at least one of the amplifying solid state elements of the amplifier using FETs
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03G—CONTROL OF AMPLIFICATION
- H03G1/00—Details of arrangements for controlling amplification
- H03G1/0005—Circuits characterised by the type of controlling devices operated by a controlling current or voltage signal
- H03G1/0088—Circuits characterised by the type of controlling devices operated by a controlling current or voltage signal using discontinuously variable devices, e.g. switch-operated
Abstract
The invention provides a rotary transformer signal modulation circuit and a motor driving system, wherein the rotary transformer signal modulation circuit comprises a rotary digital converter, an operational amplification circuit, a resistance feedback circuit and a push-pull circuit, wherein the rotary digital converter is used for outputting differential excitation signals, the operational amplification circuit is used for amplifying the differential excitation signals output by the rotary digital converter, the push-pull circuit is used for push-pull outputting the signals amplified by the operational amplification circuit to the rotary transformer, and the resistance feedback circuit is used for adjusting the amplification factor of the operational amplification circuit. The rotary transformer signal modulation circuit can be suitable for rotary transformers with two different transformation ratios.
Description
Technical Field
The invention relates to the field of motor driving, in particular to a rotary transformer signal modulation circuit and a motor driving system.
Background
With the gradual exhaustion of reserves of non-renewable energy sources such as petroleum, coal and the like, people start to reasonably utilize renewable energy sources such as solar energy, wind power and water power. Among them, wind power generation is a technology which has been developed relatively mature in new energy power generation technology, and has been used as the key point of new energy development strategy in China; in the automobile industry, new energy pure electric and hybrid automobiles are gradually replacing the traditional fuel automobiles.
The wind power variable pitch system is one of key components of wind power generation, and mainly aims to change the angle of blades according to the output power of a wind power generator so as to ensure that the power generator is within rated power. The main motor driver is one of key components of the electric automobile and mainly used for receiving an instruction of the main drive controller to control the motor to run so as to drive the automobile to run. In order to ensure the normal operation of the pitch system and the electric vehicle, the rotation speed of the motor must be accurately measured so as to make the motor run stably. The motors used in the pitch system and the electric automobile in the market at present are mainly permanent magnet synchronous motors, and the most main component of speed detection equipment in the permanent magnet synchronous motors is a rotary transformer. In order to ensure the efficiency of the wind power generator and the stable operation of the motor of the electric automobile, the accuracy of the speed and the position measured by the rotary transformer is required to be ensured.
The current market is that the main rotary transformer manufacturers have a plurality of Moghania and Haihan De, and the conversion ratio is mainly 0.5 and 0.28. In order to meet the excitation requirements of rotary transformers with different transformation ratios, excitation signals are modulated by adopting amplifying circuits with different amplification factors. In the existing rotary transformer excitation signal processing circuit, the amplification factor is mainly changed by changing the single-plate resistor BOM mode or manually removing the rotary adjustable resistor to change the amplification factor so as to adapt to the rotary transformer with different transformation ratios.
Disclosure of Invention
The invention aims to provide a rotary transformer signal modulation circuit and a motor driving system, which are used for solving the technical problem that the rotary transformer signal modulation circuit in the prior art cannot meet the application requirements of rotary transformers with different transformation ratios in a self-adaptive manner.
The embodiment of the invention provides a signal modulation circuit of a rotary transformer, which comprises a rotary digital converter, an operational amplification circuit, a resistance feedback circuit and a push-pull circuit, wherein the rotary digital converter is used for outputting a differential excitation signal, the operational amplification circuit is used for amplifying the differential excitation signal output by the rotary digital converter, the push-pull circuit is used for push-pull outputting the signal amplified by the operational amplification circuit to the rotary transformer, and the resistance feedback circuit is used for adjusting the amplification factor of the operational amplification circuit.
In the embodiment of the invention, the operational amplifier circuit comprises an operational amplifier U1, resistors R9 and R10, wherein the non-inverting input end of the operational amplifier U1 is connected with a 5V power supply through the resistor R10, and the inverting input end of the operational amplifier U1 is connected with the differential excitation signal output end of the rotary transformer through the resistor R9.
In the embodiment of the invention, the operational amplifier circuit further comprises a resistor R12 and a capacitor C4 connected in parallel between the non-inverting input end of the operational amplifier U1 and the ground.
In the embodiment of the present invention, the rotary digital converter uses a rotary decoding chip AD2S1210.
In this embodiment of the present invention, the push-pull circuit includes diodes D1, D2, resistors R3, R4, R5, R6, R7, R8, bipolar transistors Q1, Q2, and a modulating signal output terminal exc_p, where the positive electrode of the diode D1 is connected to the output terminal of the operational amplifier U1, the negative electrode of the diode D1 is connected to the base of the bipolar transistor Q1 through the resistor R3, the collector of the bipolar transistor Q1 is connected to the 12V power supply, the emitter of the bipolar transistor Q1 is connected to the modulating signal output terminal exc_p through the resistor R5, the resistor R7 is connected between the base and the collector of the bipolar transistor Q1, the negative electrode of the diode D2 is connected to the output terminal of the operational amplifier U1, the positive electrode of the diode D2 is connected to the base of the bipolar transistor Q2 through the resistor R4, the collector of the bipolar transistor Q2 is grounded, the emitter of the bipolar transistor Q2 is connected to the modulating signal output terminal c_p through the resistor R6, and the resistor R8 is connected between the base and the collector of the bipolar transistor Q2.
In the embodiment of the invention, the resistor feedback circuit comprises resistors R11 and R14 and a switch circuit, wherein the resistor R14 is connected between the inverting input end of the operational amplifier U1 and the modulation signal output end EXC_P, the resistor R11 and the switch circuit are connected in series and then connected with the resistor R14 in parallel, and the switch circuit is used for controlling the on-off of a circuit where the resistor R11 is located.
In the embodiment of the invention, the switch circuit includes resistors R13, R15, R16, field effect transistors Q3, Q4 and a signal feedback terminal SW0, the resistors R13, R15 are connected in series between ground and a 5V power supply, the signal feedback terminal SW0 is connected to a connection point of the resistors R13, R15 through the resistor R16, gates of the field effect transistors Q3, Q4 are respectively connected to a connection point of the resistors R13, R15, a drain of the field effect transistor Q3 is connected to a drain of the field effect transistor Q4, an emitter of the field effect transistor Q3 is connected to a modulation signal output terminal exc_p through the resistor R11, and an emitter of the field effect transistor Q4 is connected to an inverting input terminal of the operational amplifier U1.
In the embodiment of the present invention, the resistor feedback circuit further includes a capacitor C5 connected between the inverting input terminal of the operational amplifier U1 and the modulation signal output terminal exc_p.
In the embodiment of the invention, the resolver signal modulation circuit further comprises a controller, and the controller is used for controlling the level of the signal feedback end SW0 according to the feedback signal of the resolver digital converter, so as to control the amplification factor of the operational amplification circuit.
In an embodiment of the present invention, a motor driving system is further provided, which includes a resolver and the resolver signal modulation circuit described above.
Compared with the prior art, by adopting the technical scheme, the operational amplification circuit is used for amplifying the differential excitation signal output by the rotary digital converter, the push-pull circuit is used for outputting the signal amplified by the operational amplification circuit to the rotary transformer in a push-pull way, the resistance feedback circuit is used for adjusting the amplification factor of the operational amplification circuit, and the amplification factor of the operational amplification circuit can be adjusted by adjusting the feedback resistance of the resistance feedback circuit, so that the rotary transformer signal modulation circuit can be used for adaptively meeting the application requirements of rotary transformers with different transformation ratios.
Drawings
Fig. 1 is a schematic diagram of a resolver signal modulation circuit according to an embodiment of the present invention.
Fig. 2 is a control flow chart of a resolver signal modulation circuit according to an embodiment of the present invention.
Detailed Description
The present invention will be described in further detail with reference to the drawings and examples, in order to make the objects, technical solutions and advantages of the present invention more apparent. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the invention.
As shown in fig. 1, in an embodiment of the present invention, there is provided a signal modulation circuit of a resolver, which includes a resolver digitizer 1, an operational amplification circuit 2, a push-pull circuit 3, a resistance feedback circuit 4, and a controller 5. The rotary digital converter 1 is used for outputting a differential excitation signal, the operational amplification circuit 2 is used for amplifying the differential excitation signal output by the rotary digital converter 1, the push-pull circuit 3 is used for push-pull outputting the signal amplified by the operational amplification circuit 2 to the rotary transformer to the rotary digital converter 1, the resistance feedback circuit 4 is used for adjusting the amplification factor of the operational amplification circuit 2, and the controller 5 is used for detecting the signal fed back by the rotary digital converter 1 and controlling the resistance of the resistance feedback circuit 4 according to the signal fed back by the rotary digital converter 1 so as to control the amplification factor of the operational amplification circuit 2.
The rotary digital converter 1 adopts a rotary decoding chip AD2S1210, and the peak-to-peak value output by the differential excitation signal output end EXC_S_N is 3.6V, and the frequency is 10kHz excitation signal.
The operational amplifier circuit 2 includes an operational amplifier U1, resistors R9, R10, R12, and a capacitor C4. The noninverting input end of the operational amplifier U1 is connected with a 5V power supply through a resistor R10, and the inverting input end of the operational amplifier U1 is connected with the differential excitation signal output end EXC_S_N of the rotary transformer through a resistor R9. Resistor R12 and capacitor C4 are connected in parallel between the non-inverting input of op-amp U1 and ground.
The push-pull circuit 3 comprises diodes D1, D2, resistors R3, R4, R5, R6, R7, R8, bipolar transistors Q1, Q2 and a modulation signal output end exc_p, wherein the positive electrode of the diode D1 is connected with the output end of the operational amplifier U1, the negative electrode of the diode D1 is connected with the base electrode of the bipolar transistor Q1 through the resistor R3, the collector electrode of the bipolar transistor Q1 is connected with a 12V power supply, the emitter electrode of the bipolar transistor Q1 is connected with the modulation signal output end exc_p through the resistor R5, the resistor R7 is connected between the base electrode and the collector electrode of the bipolar transistor Q1, the negative electrode of the diode D2 is connected with the output end of the operational amplifier U1, the positive electrode of the diode D2 is connected with the base electrode of the bipolar transistor Q2 through the resistor R4, the collector electrode of the bipolar transistor Q2 is grounded, the emitter electrode of the bipolar transistor Q2 is connected with the modulation signal output end exc_p through the resistor R6, and the resistor R8 is connected between the base electrode and the collector electrode of the bipolar transistor Q2. The modulation signal output end EXC_P is connected to the rotary transformer.
The resistor feedback circuit 4 comprises resistors R11, R13, R14, R15, R16, a capacitor C5, field effect transistors Q3 and Q4 and a signal feedback end SW0, the resistor R14 is connected between an inverting input end of the operational amplifier U1 and a modulating signal output end exc_p, the resistors R13 and R15 are connected in series with a ground and a 5V power supply, the signal feedback end SW0 is connected to a connection point of the resistors R13 and R15 through the resistor R16, gates of the field effect transistors Q3 and Q4 are respectively connected to a connection point of the resistors R13 and R15, a drain electrode of the field effect transistor Q3 is connected with a drain electrode of the field effect transistor Q4, an emitter electrode of the field effect transistor Q3 is connected with the modulating signal output end exc_p through the resistor R11, and an emitter electrode of the field effect transistor Q4 is connected with an inverting input end of the operational amplifier U1. The capacitor C5 is connected between the inverting input terminal of the operational amplifier U1 and the modulation signal output terminal exc_p. The resistors R13, R15, R16, the field effect transistors Q3, Q4, and the signal feedback terminal SW0 form a switching circuit, which is used for controlling the on-off of the line where the resistor R11 is located, so as to control the feedback resistance value of the resistor feedback circuit 4.
The controller 5 is configured to control the level of the signal feedback terminal SW0 according to the feedback signal of the rotary digitizer 1, so as to control the amplification factor of the operational amplifying circuit. .
The working principle of the rotary transformer signal modulation circuit is as follows:
the differential exciting signal output by the rotary digital converter 1 is amplified by an operational amplifier U1, and then is push-pull output to a rotary transformer by bipolar transistors Q1 and Q2, so that the carrying capacity of the exciting signal is improved. The two diodes D1 and D2 are connected, so that 0.6V compensation voltage can be added on the bases of the bipolar transistors Q1 and Q2 to offset dead zones of the transistors, and switching distortion of output waveforms can be effectively avoided.
The field effect transistors Q3 and Q4 form a switch circuit, which is used for controlling the on-off of the resistor R11, and the level of the SW0 signal is controlled by the controller 5, so as to control the on-off of the field effect transistors Q3 and Q4, thereby realizing the purpose of changing the amplification factor of the operational amplifier circuit 2 by controlling the on-off of the R11 in the feedback loop, and further being suitable for driving the rotary transformer with the transformation ratio of 0.5 and 0.28. The amplification factor is A1 when R11 is on (A1 < A2), and the amplification factor is A2 when R11 is off.
Specifically, in the circuit with the amplification factor A1, the relation between the output voltage Uo of the modulation signal output terminal exc_p and the voltage Ui of the differential excitation signal output terminal exc_s_n of the rotary digital converter 1 is as follows:
in the circuit with the amplification factor A2, the relation between the output voltage Uo of the output signal exc_p and the input voltage Ui of the input signal exc_s_n is:
as shown in fig. 2, when the motor is powered on, the level signal of the signal feedback terminal SW0 is configured as a high level "1", at this time, R11 is turned on, the amplification factor of the operational amplification circuit 2 is A1, if the transformation ratio of the resolver is 0.5, the differential signal returned by the resolver can satisfy the signal input range of the resolver digital converter 1, and the controller 5 maintains the high level output to the signal feedback terminal SW 0. If the transformation ratio of the rotary transformer on the motor is 0.28, the differential signal amplitude returned by the rotary transformer is lower than 2.2V, the rotary digital converter 1 will report a signal loss fault, the controller 5 configures the level signal of the signal feedback end SW0 to be low level 0 when detecting the fault, at this moment, R11 is disconnected, the amplification factor of the operational amplifier circuit 2 is A2, at this moment, the differential signal output by the rotary transformer with the transformation ratio of 0.28 can meet the signal amplitude input range of the rotary digital converter 1.
Further, in an embodiment of the present invention, a motor driving system is provided, which includes a resolver and the resolver signal modulation circuit described above.
In summary, by adopting the above technical solution, the operational amplification circuit is configured to amplify the differential excitation signal output by the rotary digital converter, the push-pull circuit is configured to push-pull output the signal amplified by the operational amplification circuit to the rotary transformer, and the resistance feedback circuit is configured to adjust the amplification factor of the operational amplification circuit, and the amplification factor of the operational amplification circuit may be adjusted by adjusting the feedback resistance of the resistance feedback circuit, so that the rotary transformer signal modulation circuit may adaptively meet the application requirements of rotary transformers with different transformation ratios.
The foregoing description of the preferred embodiments of the invention is not intended to be limiting, but rather is intended to cover all modifications, equivalents, and alternatives falling within the spirit and principles of the invention.
Claims (5)
1. The signal modulation circuit of the rotary transformer is characterized by comprising a rotary digital converter, an operational amplification circuit, a resistance feedback circuit and a push-pull circuit, wherein the rotary digital converter is used for outputting a differential excitation signal, the operational amplification circuit is used for amplifying the differential excitation signal output by the rotary digital converter, the push-pull circuit is used for push-pull outputting the signal amplified by the operational amplification circuit to the rotary transformer, and the resistance feedback circuit is used for adjusting the amplification factor of the operational amplification circuit; the operational amplification circuit comprises an operational amplifier U1, resistors R9 and R10, wherein the non-inverting input end of the operational amplifier U1 is connected with a 5V power supply through the resistor R10, and the inverting input end of the operational amplifier U1 is connected with the differential excitation signal output end of the rotary digital converter through the resistor R9; the operational amplifier circuit further comprises a resistor R12 and a capacitor C4 which are connected in parallel between the non-inverting input end of the operational amplifier U1 and the ground; the push-pull circuit comprises diodes D1, D2, resistors R3, R4, R5, R6, R7 and R8, bipolar transistors Q1 and Q2 and a modulation signal output end EXC_P, wherein the negative electrode of the diode D1 is connected with the output end of an operational amplifier U1, the positive electrode of the diode D1 is connected with the base electrode of the bipolar transistor Q1 through the resistor R3, the collector electrode of the bipolar transistor Q1 is connected with a 12V power supply, the emitter electrode of the bipolar transistor Q1 is connected with the modulation signal output end EXC_P through the resistor R5, the resistor R7 is connected between the base electrode and the collector electrode of the bipolar transistor Q1, the positive electrode of the diode D2 is connected with the output end of an operational amplifier U1, the negative electrode of the diode D2 is connected with the base electrode of the bipolar transistor Q2 through the resistor R4, the collector electrode of the bipolar transistor Q2 is grounded, the emitter electrode of the bipolar transistor Q2 is connected with the modulation signal output end EXC_P through the resistor R6, and the resistor R8 is connected between the base electrode and the collector electrode of the bipolar transistor Q2; the resistor feedback circuit comprises resistors R11 and R14 and a switch circuit, wherein the resistor R14 is connected between the inverting input end of the operational amplifier U1 and the modulation signal output end EXC_P, the resistor R11 and the switch circuit are connected in series and then connected with the resistor R14 in parallel, and the switch circuit is used for controlling the on-off of a circuit where the resistor R11 is positioned; the switching circuit comprises resistors R13, R15 and R16, field effect transistors Q3 and Q4 and a signal feedback end SW0, wherein the resistors R13 and R15 are connected in series between the ground and a 5V power supply, the signal feedback end SW0 is connected to the connection points of the resistors R13 and R15 through the resistor R16, the grid electrodes of the field effect transistors Q3 and Q4 are respectively connected to the connection points of the resistors R13 and R15, the source electrode of the field effect transistor Q3 is connected with the source electrode of the field effect transistor Q4, the drain electrode of the field effect transistor Q3 is connected with a modulation signal output end EXC_P through the resistor R11, and the drain electrode of the field effect transistor Q4 is connected with the inverting input end of the operational amplifier U1.
2. The signal modulation circuit of claim 1, wherein the rotary digital converter employs a rotary decoding chip AD2S1210.
3. The signal modulation circuit of claim 1, wherein the resistive feedback circuit further comprises a capacitor C5 connected between the inverting input terminal of the operational amplifier U1 and the modulated signal output terminal exc_p.
4. The signal modulation circuit of claim 1, further comprising a controller for controlling a level of the signal feedback terminal SW0 according to a feedback signal of the rotary digitizer, thereby controlling an amplification factor of the operational amplification circuit.
5. A motor drive system comprising a resolver and a signal modulation circuit of the resolver according to any one of claims 1 to 4.
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| CN201910023859.7A CN109660209B (en) | 2019-01-10 | 2019-01-10 | Rotary transformer signal modulation circuit and motor driving system |
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| CN201910023859.7A CN109660209B (en) | 2019-01-10 | 2019-01-10 | Rotary transformer signal modulation circuit and motor driving system |
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| CN109660209A CN109660209A (en) | 2019-04-19 |
| CN109660209B true CN109660209B (en) | 2023-07-21 |
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| DE10049774C2 (en) * | 2000-09-29 | 2002-11-07 | Infineon Technologies Ag | Push-pull output stage for digital signals with regulated output levels |
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| CN203327029U (en) * | 2013-08-14 | 2013-12-04 | 曾淑涛 | Rotary voltage transformation signal conversion equipment applied to inertial navigation system |
| US20150207444A1 (en) * | 2014-01-21 | 2015-07-23 | GM Global Technology Operations LLC | Motor controller with enhanced wobble compensation |
| CN204271968U (en) * | 2014-11-28 | 2015-04-15 | 湖北三江航天红峰控制有限公司 | A kind of resolver digital decoding control circuit based on DSP |
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| EP0768515A1 (en) * | 1995-10-16 | 1997-04-16 | Texas Instruments Inc. | Variable differential transformer apparatus and method |
| CN101777839A (en) * | 2009-01-08 | 2010-07-14 | 中国电子为华实业发展有限公司 | Switch power supply device applying piezoelectric transformer |
| CN104977974A (en) * | 2015-06-18 | 2015-10-14 | 杭州长川科技股份有限公司 | Integral control module used for heavy current power device test system |
| WO2017121955A1 (en) * | 2016-01-14 | 2017-07-20 | Valeo Systemes De Controle Moteur | Excitation circuit for a resolver |
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