A PWM pulse width modulation encoder test circuit

Abstract

The utility model relates to a kind of PWM pulse width modulation encoder test circuit, including input module, joystick module and test module, wherein, the joystick module includes single-axis joystick U15, the switch of contactor K9 includes first switch and second switch, the normally open end of first switch is connected manual signal anode CM+, the normally open end of second switch is connected manual signal cathode CM-;The common end of first switch is connected the positive input end of manual comparator CM of encoder module, the common end of second switch is connected the reverse input end of manual comparator CM of encoder module, single-axis joystick U15 inside is equipped with the coil of contactor K9, the coil of contactor K9 connects the input voltage end of single-axis joystick U15.Compared with prior art, the utility model has the advantages that the traction, braking system of train can be accurately responded, and the stable control of train is realized.

Description

Technical Field

[0001] This utility model relates to the technical field of encoder testing, and in particular to a PWM pulse width modulation encoder testing circuit. Background Technology

[0002] In distributed power rail vehicles, common methods for reliably transmitting traction and braking signals from the autonomous controller or automatic train control (ATO) to the traction and braking control units distributed across each car include communication network-based methods and hardware wiring. Due to the reliability principle of "hard wire priority," pulse width modulation (PWM) is used in railway EMUs and light rail vehicles to transmit traction and braking commands.

[0003] PWM encoders are critical components in automotive electronics that significantly impact vehicle safety. Their reliability must be a primary consideration in the design. PWM encoders must possess robust real-time self-testing capabilities. Upon detecting a fault, they must isolate invalid outputs and notify the control circuit's interlocking relays via the PWM encoder's operating status relay to implement necessary safety measures. Detecting the microcontroller's proper functioning solely through a watchdog timer is insufficient; a reliable dynamic monitoring circuit should be incorporated into the PWM output circuit to provide real-time monitoring of the microcontroller and pulse width modulation module.

[0004] Pulse width modulation (PWM) can be implemented analogally or digitally. The analog approach involves sending a given voltage value and the output of a sawtooth multivibrator to a comparator, which then outputs a modulated rectangular wave. The digital approach primarily consists of a clock source, latches, a period counter, a pulse width counter, and AND gate logic; it can also be implemented using an integrated timer chip.

[0005] Currently, the detection of the working status of PWM encoders in manual mode is not perfect. The input voltage of the joystick in manual mode is rarely detected. When the automatic mode fails and the manual mode needs to be activated urgently, the failure of the joystick will cause the entire PWM encoder to fail to start, and it will be unable to generate pulse width modulation (PWM) waves to control the train's traction and braking equipment, thus affecting the normal operation of the train. Utility Model Content

[0006] The purpose of this invention is to provide a PWM encoder test circuit to overcome the generation failure of pulse width modulation (PWM) waves used to control train operation in manual mode.

[0007] The objective of this utility model can be achieved through the following technical solutions:

[0008] A PWM (Pulse Width Modulation) encoder test circuit is used in an encoder module, including an input module, a joystick module, and a test module. The joystick module includes a single-axis joystick U15, switches for contactors K2, K3, K4, K5, K6, and K9. The contactor K9 switch includes a first switch and a second switch. The normally open terminal of the first switch is connected to the positive terminal CM+ of the manual signal, and the normally open terminal of the second switch is connected to the negative terminal CM- of the manual signal. The common terminal of the first switch is connected to the positive input terminal of the manual comparator CM of the encoder module, and the common terminal of the second switch is connected to the inverted input terminal of the manual comparator CM of the encoder module. The single-axis joystick U15 contains a coil for the contactor K9.

[0009] The normally open terminal of contactor K2 is connected to the positive high-voltage input B+, the common terminal of contactor K2 is connected to the positive power supply voltage terminal +BT of the encoder module, and the negative power supply voltage terminal -BT of the encoder module is connected to the negative high-voltage input B-.

[0010] The high voltage input positive terminal B+ and the high voltage input negative terminal B- are connected to the high voltage and current detector U11 of the test module, and the inverting input terminal of the manual comparator CM and the input voltage terminal of the single-axis joystick U15 are connected to the low voltage and current detector U12 of the test module.

[0011] The output of the manual comparator CM and the input voltage terminal of the single-axis joystick U15 are connected to the PWM module in the encoder module. The PWM module includes two signal generators A1 and A2. The output terminals of the two signal generators are respectively connected to the two input terminals of the PWM comparator A3 of the PWM module. The output terminal of the PWM comparator A3 is connected to the two positive output terminals of the PWM signal.

[0012] Furthermore, the normally open terminals of both contactor K3 and contactor K4 are connected to the high-voltage input positive terminal B+. The common terminal of contactor K3 is connected to the first voltage input terminal IN1 of the PWM module, and the common terminal of contactor K4 is connected to the second voltage input terminal IN2 of the PWM module. The first voltage input terminal IN1 and the second voltage input terminal IN2 are respectively connected to the power supply terminals of the two signal generators.

[0013] Furthermore, the output of the manual comparator CM is connected to one end of the control coil A4 of the PWM module, the other end of the control coil A4 is grounded, the normally open terminal of the control switch A5 corresponding to the control coil A4 is connected to the positive output terminal of the PWM signal, and the common terminal of the control switch A5 is connected to the output terminal of the PWM comparator.

[0014] Furthermore, the input voltage terminal of the single-axis joystick U15 is connected to the voltage input terminal of the PWM comparator A3.

[0015] Furthermore, the input voltage terminal of the single-axis joystick U15 is connected to the PWM module in the encoder module through resistor R2.

[0016] Furthermore, the common terminal of the first switch is connected to the positive input terminal of the manual comparator CM of the encoder module through resistor R4.

[0017] Furthermore, the common terminal of contactor K5 and the common terminal of contactor K6 are grounded, and the normally open terminals of contactor K5 and contactor K6 are connected to the negative output terminal of the PWM signal.

[0018] Furthermore, the PWM module also includes an automatic comparator (ATO).

[0019] Furthermore, the power supply terminals of the high-voltage voltage and current detector U11 and the low-voltage voltage and current detector U12 are connected to the output terminal of the low-voltage power supply V1, and the output terminal of the high-voltage power supply V2 of the input module is connected to the high-voltage input positive terminal B+ and the high-voltage input negative terminal B-.

[0020] Furthermore, the inputs of the high-voltage power supply V2 and the low-voltage power supply V1 are connected to the common terminal of the contactor K8, and the normally closed terminal of the contactor K8 is connected to the leakage current protector Q1. The leakage current protector Q1 is connected to the initial input voltage.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] This invention, in addition to detecting the common terminal circuit, adds detection of the joystick input voltage in manual mode. This ensures the normal operation of the power supply to the encoder's PWM module and the working voltage of the manual and automatic comparators. Simultaneously, it integrates the voltage measurement of the common terminal to guarantee the normal operation of the switching sections of each contactor and the encoder power supply. A stable input voltage is a prerequisite for the PWM encoder to accurately convert the joystick position signal into a PWM signal. Detecting the input voltage ensures the accuracy and stability of the encoder output signal, enabling the train's traction and braking systems to respond precisely and achieve smooth train control. Attached Figure Description

[0023] Figure 1 This is a schematic diagram showing the initial input voltage connected to the input module of this utility model;

[0024] Figure 2 This is a schematic diagram of the input module of this utility model;

[0025] Figure 3 A schematic diagram for controlling the contactor coil;

[0026] Figure 4 This is a schematic diagram of the joystick module and the encoder module;

[0027] Figure 5 This is a schematic diagram of the test module;

[0028] Figure 6 This is a schematic diagram of a PWM module. Detailed Implementation

[0029] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. This embodiment is based on the technical solution of the present invention and provides detailed implementation methods and specific operating procedures; however, the scope of protection of the present invention is not limited to the following embodiments.

[0030] This utility model proposes a PWM pulse width modulation encoder test circuit for an encoder module. It is characterized by comprising an input module, a joystick module, and a test module. The joystick module includes a single-axis joystick U15, switches for contactors K2, K3, K4, K5, K6, and K9. The contactor K9 switch includes a first switch and a second switch. The normally open terminal of the first switch is connected to the positive terminal CM+ of the manual signal, and the normally open terminal of the second switch is connected to the negative terminal CM- of the manual signal. The common terminal of the first switch is connected to the positive input terminal of the manual comparator CM of the encoder module, and the common terminal of the second switch is connected to the inverted input terminal of the manual comparator CM of the encoder module. The single-axis joystick U15 contains a coil for contactor K9, and the coil of contactor K9 is connected to the input voltage terminal of the single-axis joystick U15.

[0031] The normally open terminal of contactor K2 is connected to the positive high-voltage input B+, the common terminal of contactor K2 is connected to the positive power supply voltage terminal +BT of the encoder module, and the negative power supply voltage terminal -BT of the encoder module is connected to the negative high-voltage input B-.

[0032] The high voltage input positive terminal B+ and the high voltage input negative terminal B- are connected to the high voltage and current detector U11 of the test module, and the inverting input terminal of the manual comparator CM and the input voltage terminal of the single-axis joystick U15 are connected to the low voltage and current detector U12 of the test module.

[0033] The output of the manual comparator CM and the input voltage terminal of the single-axis joystick U15 are connected to the PWM module in the encoder module. The PWM module includes two signal generators. The output terminals of the two signal generators are respectively connected to the two input terminals of the PWM comparator of the PWM module. The output terminal of the PWM comparator is connected to the two positive output terminals of the PWM signal. Figure 1 This is a schematic diagram showing the initial input voltage connected to the input module of this utility model;

[0034] Figure 2 This is a schematic diagram of the input module of this utility model. Figure 4 This is a schematic diagram of the joystick module and the encoder module; Figure 5 This is a schematic diagram of the test module; Figure 6 This is a schematic diagram of a PWM module.

[0035] The normally open terminals of contactor K3 and contactor K4 are both connected to the high voltage input positive terminal B+. The common terminal of contactor K3 is connected to the first voltage input terminal IN1 of the PWM module, and the common terminal of contactor K4 is connected to the second voltage input terminal IN2 of the PWM module. The first voltage input terminal IN1 and the second voltage input terminal IN2 are respectively connected to the power supply terminals of the two signal generators.

[0036] The output of the manual comparator CM is connected to one end of the control coil of the PWM module, and the other end of the control coil is grounded. The normally open terminal of the control switch corresponding to the control coil is connected to the positive output terminal of the PWM signal, and the common terminal of the control switch is connected to the output of the PWM comparator.

[0037] The input voltage terminal of the single-axis joystick U15 is connected to the voltage input terminal of the PWM comparator.

[0038] The input voltage terminal of the single-axis joystick U15 is connected to the PWM module in the encoder module through resistor R2.

[0039] The common terminal of the first switch is connected to the positive input terminal of the manual comparator CM of the encoder module through resistor R4.

[0040] The common terminal of contactor K5 and the common terminal of contactor K6 are grounded, and the normally open terminals of contactor K5 and contactor K6 are connected to the negative output terminal of the PWM signal.

[0041] The PWM module also includes an automatic comparator (ATO).

[0042] The input voltage terminal of the single-axis joystick U15 is connected to the power supply terminals of the high-voltage voltage and current detector U11 and the low-voltage voltage and current detector U12. The power supply terminals of the high-voltage voltage and current detector U11 and the low-voltage voltage and current detector U12 are connected to the output terminals of the high-voltage power supply V2 of the input module, namely the high-voltage input positive terminal B+ and the high-voltage input negative terminal B-, and the output terminal of the low-voltage power supply V1.

[0043] The input module includes a high-voltage power supply V2 and a low-voltage power supply V1. The inputs of the high-voltage power supply V2 and the low-voltage power supply V1 are connected to the common terminal of contactor K8. The normally closed terminal of contactor K8 is connected to the leakage current protector Q1. The leakage current protector Q1 is connected to the initial input voltage.

[0044] In manual operation, the coil of contactor K9 is connected to the normally open terminal of the internal switch of the joystick, and the common terminal of the internal switch is connected to the input voltage terminal of the single-axis joystick U15. When the single-axis joystick is operated, the internal switch closes, and the normally open terminal and the common terminal of the internal switch are connected, so that the voltage at the input voltage terminal of U15 is applied to the coil of contactor K9, causing the contactor K9 to close. At this time, the positive and negative signals of the manual signal CM+ and CM- are connected to the manual comparator CM. The output level of the manual comparator CM is applied to the control coil of the PWM module, the control switch corresponding to the control coil closes, the positive output terminal of the PWM signal is connected to the output terminal of the PWM comparator, and the PWM signal is output to the positive output terminal of the PWM signal module.

[0045] A schematic diagram of the control contactor coil is shown below. Figure 3 As shown. In this invention, the coils of K2, K3, K4, K5, K6, K8, and K9 can be controlled uniformly through the input end of a single-axis joystick.

[0046] One end of the coil corresponding to the switches of contactors K2, K3, K4, K5, and K6 can be connected to the input terminal. When a certain threshold voltage is present at the input terminal, the contactor switches close. During operation, the switches of contactors K2, K3, K4, K5, and K6 are closed, while the switch of contactor K8 is open.

[0047] When contactor K2 is closed, energizes the positive terminal +BT and the negative terminal -BT of the power supply voltage. An LED or similar indicator can be installed between the positive terminal +BT and the negative terminal -BT of the power supply voltage as an indicator of the presence of voltage at the positive terminal B+ of the high-voltage input.

[0048] When the switches of contactor K3 and contactor K4 are closed, power is supplied to the two signal generators respectively.

[0049] This invention, in addition to detecting the common terminal circuit, adds detection of the joystick input voltage in manual mode. This ensures the normal operation of the power supply to the encoder's PWM module and the working voltage of the manual and automatic comparators. Simultaneously, it integrates the voltage measurement of the common terminal to guarantee the normal operation of the switching sections of each contactor and the encoder power supply. A stable input voltage is a prerequisite for the PWM encoder to accurately convert the joystick position signal into a PWM signal. Detecting the input voltage ensures the accuracy and stability of the encoder output signal, enabling the train's traction and braking systems to respond precisely and achieve smooth train control.

[0050] When the switches of contactor K5 and contactor K6 are closed, the negative output terminal of the PWM signal is grounded.

[0051] In automatic operation mode, after the automatic comparator ATO receives the positive terminal of the automatic signal ATO+ and the negative terminal of the automatic signal ATO-, it can apply voltage to the control coil A4 of the PWM module.

[0052] In this utility model, the leakage current protector Q1 is model 5SU9356-1CR16, the contactors K2, K3, K4, K5, K6, K8, and K9 are model CJX2-2510 or 3TF46, V1 is a 24V power supply (such as LPL-18-24 and FY2407500), V2 is a 110V power supply (such as KJ160 and SE-800W), the single-axis joystick is model [not specified], the comparator is model TYH78BS-F20MA-24 or JP50A / JH50A or APEM 3140SAL600, the signal generator is model ZUS6000 or SDG1005, and the voltage and current detector is model UT39E+ or DZ-2405A.

[0053] The preferred embodiments of this utility model have been described in detail above. It should be understood that those skilled in the art can make numerous modifications and variations based on the concept of this utility model without creative effort. Therefore, all technical solutions that can be obtained by those skilled in the art based on the concept of this utility model through logical analysis, reasoning, or limited experimentation on the basis of existing technology should be within the scope of protection defined by the claims.

Claims

1. A PWM pulse width modulation encoder test circuit, used in an encoder module, characterized in that, The system includes an input module, a joystick module, and a test module. The joystick module includes a single-axis joystick U15, switches for contactors K2, K3, K4, K5, K6, and K9. The contactor K9 switch includes a first switch and a second switch. The normally open terminal of the first switch is connected to the positive terminal CM+ of the manual signal, and the normally open terminal of the second switch is connected to the negative terminal CM- of the manual signal. The common terminal of the first switch is connected to the positive input terminal of the manual comparator CM of the encoder module, and the common terminal of the second switch is connected to the inverted input terminal of the manual comparator CM of the encoder module. The single-axis joystick U15 contains the coil of contactor K9. The normally open terminal of contactor K2 is connected to the positive high-voltage input B+, the common terminal of contactor K2 is connected to the positive power supply voltage terminal +BT of the encoder module, and the negative power supply voltage terminal -BT of the encoder module is connected to the negative high-voltage input B-. The high voltage input positive terminal B+ and the high voltage input negative terminal B- are connected to the high voltage and current detector U11 of the test module, and the inverting input terminal of the manual comparator CM and the input voltage terminal of the single-axis joystick U15 are connected to the low voltage and current detector U12 of the test module. The output of the manual comparator CM and the input voltage terminal of the single-axis joystick U15 are connected to the PWM module in the encoder module. The PWM module includes two signal generators A1 and A2. The output terminals of the two signal generators are respectively connected to the two input terminals of the PWM comparator A3 of the PWM module. The output terminal of the PWM comparator A3 is connected to the two positive output terminals of the PWM signal.

2. The PWM pulse width modulation encoder test circuit according to claim 1, characterized in that, The normally open terminals of contactor K3 and contactor K4 are both connected to the high voltage input positive terminal B+. The common terminal of contactor K3 is connected to the first voltage input terminal IN1 of the PWM module, and the common terminal of contactor K4 is connected to the second voltage input terminal IN2 of the PWM module. The first voltage input terminal IN1 and the second voltage input terminal IN2 are respectively connected to the power supply terminals of the two signal generators.

3. The PWM pulse width modulation encoder test circuit according to claim 1, characterized in that, The output of the manual comparator CM is connected to one end of the control coil A4 of the PWM module, and the other end of the control coil A4 is grounded. The normally open terminal of the control switch A5 corresponding to the control coil A4 is connected to the positive output terminal of the PWM signal, and the common terminal of the control switch A5 is connected to the output terminal of the PWM comparator.

4. The PWM pulse width modulation encoder test circuit according to claim 3, characterized in that, The input voltage terminal of the single-axis joystick U15 is connected to the voltage input terminal of the PWM comparator A3.

5. A PWM pulse width modulation encoder test circuit according to claim 1, characterized in that, The input voltage terminal of the single-axis joystick U15 is connected to the PWM module in the encoder module through resistor R2.

6. The PWM pulse width modulation encoder test circuit according to claim 1, characterized in that, The common terminal of the first switch is connected to the positive input terminal of the manual comparator CM of the encoder module through resistor R4.

7. A PWM pulse width modulation encoder test circuit according to claim 1, characterized in that, The common terminal of contactor K5 and the common terminal of contactor K6 are grounded, and the normally open terminals of contactor K5 and contactor K6 are connected to the negative output terminal of the PWM signal.

8. A PWM pulse width modulation encoder test circuit according to claim 1, characterized in that, The PWM module also includes an automatic comparator (ATO).

9. A PWM pulse width modulation encoder test circuit according to claim 1, characterized in that, The power supply terminals of the high-voltage voltage and current detector U11 and the low-voltage voltage and current detector U12 are connected to the output terminal of the low-voltage power supply V1. The output terminal of the high-voltage power supply V2 of the input module is connected to the high-voltage input positive terminal B+ and the high-voltage input negative terminal B-.

10. A PWM pulse width modulation encoder test circuit according to claim 9, characterized in that, The inputs of high-voltage power supply V2 and low-voltage power supply V1 are connected to the common terminal of contactor K8. The normally closed terminal of contactor K8 is connected to leakage current protection device Q1, and leakage current protection device Q1 is connected to the initial input voltage.

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