Signal processing circuit of Hall type and magnetic braiding type motor position sensor

Abstract

The utility model belongs to the technical field of sensor circuits, and particularly relates to a signal processing circuit of a Hall type and magnetic braiding type motor position sensor, which comprises a switching circuit, a voltage division circuit and a filter circuit, wherein the switching circuit is composed of a phase inverter U2A and three analog switches U1A, U1B and U1C; the voltage division circuit consists of a resistor R1 and a resistor R2 and is used for regulating and controlling circuit voltage; the filter circuit is composed of an R3 and a C1, and can effectively filter a frequency point of a specific frequency or a frequency except the frequency point to obtain a required effective signal. The motor controller designed by adopting the circuit of the utility model can support motors of two types of sensors at the same time, has strong compatibility, can reduce product types of companies, saves material management and product management cost, and simultaneously consists of conventional RC (Resistance-Capacitance) elements and most basic logic devices, such as an inverter chip and an analog switch chip. The circuit is simple and easy to realize, few in devices and low in cost.

Description

Technical Field

[0001] The utility model belongs to the technical field of sensor circuits, and in particular relates to a signal processing circuit of a Hall type and a magnetic encoding type motor position sensor. Background Art

[0002] In most current low-voltage electric vehicle power systems, Hall-type position sensor permanent magnet synchronous motors (hereinafter referred to as "Hall motors" and "Hall sensors") are used as drive motors. However, due to the inherent low resolution of Hall sensors, the vehicles experience low-speed unevenness and start-up jitters. In recent years, with the development of technology, magnetic position sensor permanent magnet synchronous motors (hereinafter referred to as "magnetic motors" and magnetic sensors) have become more mature. Since magnetic sensors have higher resolution, they can greatly improve low-speed unevenness and start-up jitters of vehicles. However, their cost is higher than that of Hall motors, so magnetic motor power systems are usually used when comfort requirements are high and costs are allowed.

[0003] Because the circuit structures of Hall sensors and magnetic sensors are different, Hall sensors have open-drain output and magnetic sensors have push-pull output. Therefore, in order to adapt to different motors, the current existing solution is that the motor controller must use different position sensor signal processing circuits separately. ( Figure 1 For the existing Hall sensor signal processing circuit, Figure 2 The existing magnetic sensor signal processing circuit is used for the two motors, so the hardware circuit is not universal, which requires the addition of new PCB and control board specifications and product specifications, while increasing development costs and material management and product management costs; ultimately, the two motors need to be matched with two motor controller products and are not compatible with each other;

[0004] Therefore, the utility model proposes a signal processing circuit for Hall type and magnetic encoder type motor position sensors, thereby effectively improving the above problems. Utility Model Content

[0005] In order to solve the above-mentioned problems existing in the prior art, the utility model provides a signal processing circuit for Hall-type and magnetically encoded motor position sensors, which supports Hall-type permanent magnet synchronous motors and magnetically encoded permanent magnet synchronous motors without changing other hardware, and has the characteristics of simple circuit, low cost, strong compatibility and saving material management and product management costs.

[0006] To achieve the above-mentioned purpose, the utility model provides the following technical solutions: a signal processing circuit of a Hall-type and magnetically encoded motor position sensor, comprising: a switching circuit, a voltage divider circuit and a filtering circuit; wherein the switching circuit is composed of an inverter U2A and three analog switches U1A, U1B and U1C; and the voltage divider circuit is composed of a resistor R1 and a resistor R2, which are used to adjust the circuit voltage; the filtering circuit is composed of R3 and C1, and can effectively filter out a specific frequency point or frequencies outside the frequency point to obtain the required effective signal.

[0007] As a preferred technical solution of the signal processing circuit of a Hall type and magnetically coded motor position sensor of the utility model, the pin 1 of the inverter U2A, the pin 5 of the analog switch U1B and the pin 6 of the analog switch U1C are connected to the control signal (Ctrl); the pin 2 of the inverter U2A is connected to the pin 13 of the analog switch U1A; the pin 2 of the analog switch U1A is connected to one end of the resistor R2;

[0008] Pin 3 of the analog switch U1B is connected to the upper end of the resistor R2; pin 8 of the analog switch U1C is connected to the input signal (Hall / QEPi) of the motor position sensor and one end of the resistor R1, and pin 9 is connected to the other end of the resistor R1 and the other end of the resistor R2. Pin 9 of the analog switch U1C is also connected to one end of the resistor R3, and the other end of the resistor R3 is connected to one end of the capacitor C1 as an output (Hall / QEPo).

[0009] As a preferred technical solution for the signal processing circuit of a Hall-type and magnetically encoded motor position sensor of the utility model, pin 1 of the analog switch U1A is connected to the ground (GND).

[0010] As a preferred technical solution for the signal processing circuit of a Hall-type and magnetically encoded motor position sensor of the utility model, the 4th pin of the analog switch U1B is connected to the power supply (VCC).

[0011] As a preferred technical solution for the signal processing circuit of a Hall type and magnetically encoded motor position sensor of the utility model, the other end of the capacitor C1 is grounded (GND).

[0012] Compared with the prior art, the beneficial effects of the utility model are: by using analog switches to change the structure of the signal processing circuit to achieve "pull-up mode" or "voltage division mode" to match different types of motor position sensors; the switching function of the utility model can be controlled in a variety of different ways, with high flexibility, such as direct hardware control, or program control after using MCU, and can also cooperate with host computer control, etc. The motor controller designed after adopting the circuit of the utility model (the motor controller product designed by the circuit of the utility model is controlled by MCU) can support motors with two sensors at the same time (without changing other hardware, it supports Hall permanent magnet synchronous motors and magnetic coded permanent magnet synchronous motors), with strong compatibility, and can also reduce the company's product types, saving material management and product management costs;

[0013] At the same time, the circuits are composed of conventional RC elements and the most basic logic devices, such as inverter chips and analog switch chips. The circuits are simple, easy to implement, with few devices and low cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0015] Figure 1 It is a schematic diagram of the existing Hall sensor conditioning and processing circuit;

[0016] Figure 2 It is a schematic diagram of the existing magnetic encoding sensor signal processing circuit;

[0017] Figure 3 This is a schematic diagram of the signal processing circuit of the utility model;

[0018] Figure 4 This is a schematic diagram of the equivalent circuit of the Hall sensor mode of the utility model;

[0019] Figure 5 This is a schematic diagram of an equivalent circuit of a magnetically coded sensor mode of the utility model;

[0020] Figure 6 This is a typical application circuit diagram of the utility model. DETAILED DESCRIPTION

[0021] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0022] Example

[0023] For ease of understanding, the following description of the embodiments only lists one of the three switching paths as an explanation, and the other two switching paths are the same.

[0024] See also Figure 3 As shown, the utility model provides the following technical solutions: a signal processing circuit of a Hall type and magnetically coded motor position sensor, including (contains) a switching circuit, a voltage divider circuit and a filter circuit;

[0025] The switching circuit is composed of an inverter U2A and three analog switches U1A, U1B and U1C (i.e., analog switch U1A, analog switch U1B, analog switch U1C);

[0026] The voltage divider circuit is composed of resistors R1 and R2, which are used to adjust the circuit voltage;

[0027] The filter circuit is composed of R3 and C1, which can effectively filter out the frequency point of a specific frequency or frequencies outside the frequency point to obtain the required effective signal.

[0028] The specific circuit connection operation form is as follows:

[0029] Specifically, the control signal (Ctrl) is connected to pin 1 of the inverter U2A, pin 5 of the analog switch U1B, and pin 6 of U1C (equivalent to pin 1 of the inverter U2A, pin 5 of the analog switch U1B, and pin 6 of the analog switch U1C being connected to the control signal (Ctrl)); pin 2 of the inverter U2A is connected to pin 13 of the analog switch U1A; pin 1 of the analog switch U1A is connected to ground (GND), and pin 2 of the analog switch U1A is connected to one end of the resistor R2; pin 4 of the analog switch U1B is connected to the ... Connect the power supply (VCC), connect the 3rd pin of the analog switch U1B to the upper end of the resistor R2; connect the 8th pin of the analog switch U1C to the input signal (Hall / QEPi) of the motor position sensor and one end of the resistor R1, connect the 9th pin to the other end of the resistor R1 and the other end of the resistor R2, and connect the 9th pin of the analog switch U1C to one end of the resistor R3. The other end of the resistor R3 is connected to one end of the capacitor C1 as the output (Hall / QEPo). The other end of the capacitor C1 is grounded (GND).

[0030] When Ctrl is high, it is the Hall sensor mode. At this time, one of the Ctrl signals is low after passing through the U2A inverter, and then sent to the 13th pin of the analog switch U1A to control it to shut down. Therefore, U1A is open in this mode and does not work; the other two Ctrl signals are directly connected to the U1B and U1C control pins of the analog switch, which are high at this time, so U1B and U1C are turned on (the circuit equivalent circuit is Figure 4 As shown in the figure, the motor sensor position signal is connected to the input of the signal processing circuit. The signal is input through the 8-pin of the analog switch U1C and output from the 9-pin (R1 is short-circuited). Then the signal is divided into two paths, one of which is connected to the lower end of R2 and input by VCC through the 4-pin of the analog switch and output through the 3-pin. It is connected to the upper end of R2 to pull up the signal. The other path is output after passing through the filter circuit composed of R3 and C1.

[0031] When Ctrl is low, it is the magnetic sensor mode. At this time, one of the Ctrl signals is high after passing through the U2A inverter, and then sent to the 13th pin of the analog switch U1A to control its conduction; the other two Ctrl signals are directly connected to the U1B and U1C control pins of the analog switch. At this time, they are low, so U1B and U1C are turned off. Therefore, U1B and U1C are equivalent to open circuits in this mode and do not work (the circuit equivalent circuit is Figure 5 As shown in the figure, the motor sensor position signal is connected to the input end of the signal processing circuit, where one end of the resistor R2 is connected to U1A of the analog switch, and the conduction of U1A is equivalent to one end of R2 being grounded, so R1 and R2 form a voltage divider circuit. After the signal is divided by the voltage divider circuit, it is output after passing through the filter circuit composed of R3 and C1.

[0032] Typical application circuits of the utility model are as follows: Figure 6 As shown, three or four signals output by the motor position sensor (Halla, Hallb, Hallc signals for Hall sensor motors, QEPa, QEPb, QEPz and PWM signals for magnetically coded motors) are respectively connected to the input ends of the signal processing circuits. After the signal processing circuit completes the processing, the output is sent to the MCU for detection. The control ports of the three-way signal processing circuits are controlled by the MCU. The level state of the control port can be controlled by the program or the host computer according to the motor type configuration, thereby matching the Hall motor or the magnetically coded motor.

[0033] In summary, cooperation Figure 1 and Figure 2 Diagram( Figure 1 It is a schematic diagram of the existing Hall sensor conditioning circuit. Figure 2 Schematic diagram of the existing magnetic encoder sensor signal processing circuit). The motor controller of the prior art cannot support motors with Hall-type and magnetic encoder sensors at the same time. The motor controller designed after adopting the circuit of the utility model can support motors with two sensors at the same time, and its compatibility is strong.

[0034] It can also reduce the company's product variety and save material management and product management costs;

[0035] Furthermore, the circuit of the utility model is composed of conventional RC elements and the most basic logic devices, such as an inverter chip and an analog switch chip, and the circuit is simple, easy to implement, has few devices and low cost.

[0036] At the same time, the utility model circuit uses the conventional PWM control chip UC28xx to build a BUCK type switching power supply by using basic logic points, avoiding the use of a dedicated BUCK control chip and using the BUCK power supply feedback method and structure built by the utility model;

[0037] Specifically, the signal processing circuit of the motor position sensor is not limited to the description in the specification and implementation mode; therefore, any equivalent changes or modifications made according to the structure, features and principles described in the scope of the patent application of the utility model should be included in the scope of the patent application of the utility model, such as:

[0038] 1. The inverter chip described in the technical solution can also be replaced by a triode, a MOS tube or other switch devices, and the analog switch can be replaced by various relays (including but not limited to electromagnetic relays, photorelays, solid-state relays, etc.) and devices with similar functions to complete the circuit of the utility model.

[0039] 2. The circuit control pin (Ctrl) described in the technical solution is controlled by the MCU in the application embodiment, and the pin level is controlled by software settings to switch the mode; the pin is not limited to MCU control, but can also be controlled by other circuits or connected to a fixed level; the mode can also be selected by connecting to the power supply or ground through a resistor. This method is directly controlled by hardware and does not rely on software, and can also complete the circuit of the utility model.

[0040] Finally, it should be noted that the above description is only a preferred embodiment of the utility model and is not intended to limit the utility model. Although the utility model is described in detail with reference to the above embodiments, those skilled in the art can still modify the technical solutions recorded in the above embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the utility model shall be included in the protection scope of the utility model.

Claims

1. A signal processing circuit for Hall type and magnetic encoder type motor position sensors, characterized in that: include: Switching circuit, voltage divider circuit and filter circuit; The switching circuit consists of an inverter U2A and three analog switches U1A, U1B and U1C; The voltage divider circuit is composed of resistors R1 and R2, which are used to adjust the circuit voltage; The filter circuit is composed of R3 and C1, which can effectively filter out the frequency point of a specific frequency or frequencies other than the frequency point to obtain the required effective signal.

2. The signal processing circuit of a Hall type and magnetically coded motor position sensor according to claim 1, characterized in that: Pin 1 of the inverter U2A, pin 5 of the analog switch U1B, and pin 6 of the analog switch U1C are connected to a control signal (Ctrl); Pin 2 of the inverter U2A is connected to pin 13 of the analog switch U1A; Pin 2 of the analog switch U1A is connected to one end of the resistor R2; Pin 3 of the analog switch U1B is connected to the upper end of the resistor R2; Pin 8 of the analog switch U1C is connected to the input signal (Hall / QEPi) of the motor position sensor and one end of the resistor R1, and pin 9 is connected to the other end of the resistor R1 and the other end of the resistor R2. Pin 9 of the analog switch U1C is also connected to one end of the resistor R3, and the other end of the resistor R3 is connected to one end of the capacitor C1 as an output (Hall / QEPo).

3. The signal processing circuit of a Hall type and magnetically coded motor position sensor according to claim 2, characterized in that: Pin 1 of the analog switch U1A is connected to ground (GND).

4. The signal processing circuit of a Hall type and magnetically coded motor position sensor according to claim 3 is characterized in that: Pin 4 of the analog switch U1B is connected to a power supply (VCC).

5. The signal processing circuit of a Hall type and magnetically coded motor position sensor according to claim 4, characterized in that: The other end of the capacitor C1 is grounded (GND).

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