JP6973346B2 - Control device - Google Patents

Description

The present invention relates to the technical field of a control device for controlling a motor mounted on a vehicle.

Due to the high frequency signal generated when the motor is controlled by this type of device, the noise level of the receiver of the broadcasting radio wave such as a radio may be deteriorated. To solve this problem, for example, (i) the switching frequency of the DC-DC converter is set to a frequency that is an integral multiple of the adjacent broadcast frequency difference of the AM broadcast wave, or (ii) the channel selection frequency of the AM broadcast wave is set. A technique has been proposed for detecting and selecting a switching frequency so that a frequency that is an integral multiple of the switching frequency of the DC-DC converter has a specified frequency difference with respect to the channel selection frequency (see Patent Document 1).

Japanese Patent Application Laid-Open No. 2002-335672

In the technique described in Patent Document 1, the switching frequency is selected only from the viewpoint of eliminating the reception interference of AM broadcasting, and there is room for improvement.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a control device capable of appropriately controlling a motor while suppressing deterioration of a noise level related to a receiver.

The control device according to one aspect of the present invention is a control device for controlling the motor in a vehicle including a motor as a drive source, a battery as a power source for the motor, and a receiver capable of receiving radio waves for broadcasting. An inverter whose one end is electrically connected to the motor and whose other end is electrically connected to the battery, a generation means for generating a carrier signal used for controlling the inverter, and the generation. Between the battery and the motor, a determination means for determining the frequency of the carrier signal generated by the means, a first detection means for detecting the distance between the vehicle and the facility that transmits the broadcasting radio wave, and the battery. The determination means includes a second detection means for detecting the current flowing through the inverter and a third detection means for detecting the temperature of the reactor contained in the inverter, and the determination means is detected when the detected distance is long. A frequency lower than that in the case where the distance is short is determined as the frequency of the carrier signal, and the determination means is a first frequency in which the frequency of the carrier signal corresponding to the detected distance is lower than a predetermined frequency. In this case, when at least one of the condition that the detected current is higher than the predetermined current value and the condition that the detected temperature is higher than the predetermined temperature is satisfied, the second condition higher than the predetermined frequency is satisfied. The frequency is determined as the frequency of the carrier signal.

It is a block diagram which shows the structure of the control device which concerns on embodiment. It is a figure which shows an example of the relationship between the distance between the source of a broadcasting radio wave, the own vehicle, and a carrier frequency. It is a flowchart which shows the operation of the control device which concerns on embodiment.

An embodiment related to the control device will be described with reference to FIGS. 1 to 3.

(composition)
The configuration of the control device according to the embodiment will be described with reference to FIG. FIG. 1 is a block diagram showing a configuration of a control device according to an embodiment.

In FIG. 1, the control device 100 is mounted on the vehicle 1. The vehicle 1 includes a motor 11 as a drive source thereof, a battery 12 as a power source for the motor 11, and a receiver 20 for a radio wave for broadcasting such as a radio or a television.

The control device 100 includes an inverter 110, a carrier signal generation unit 120, a carrier frequency selection unit 130, a distance detection unit 140, a current sensor 31, and a temperature sensor 32. The current sensor 31 detects the current flowing between the motor 11 and the battery 12. The temperature sensor 32 detects the temperature of the reactor (not shown) contained in the inverter 110.

One end of the inverter 110 is electrically connected to the motor 11, and the other end is electrically connected to the battery 12. The carrier signal generation unit 120 generates a carrier signal for PWM (Pulse Width Modulation) control of the inverter 110. Since various existing modes can be applied to the inverter 110 and the carrier signal generation unit 120, detailed description thereof will be omitted.

The distance detection unit 140 is a distance between the position of the vehicle 1 and the source of the broadcast radio wave (for example, a facility in which a broadcast antenna is installed: hereinafter, appropriately referred to as a "base station") (hereinafter, appropriately ". Distance L ") is detected. The position of the vehicle 1 may be acquired based on, for example, the output of GPS (Global Positioning System). The position of the base station may be acquired based on, for example, map information. If the base station differs depending on the frequency of the broadcasting radio wave received by the receiver 20, the position of the base station corresponding to the frequency of the broadcasting radio wave currently received by the receiver 20 is determined based on the map information. You just have to get it.

The carrier frequency selection unit 130 selects the frequency of the carrier signal generated by the carrier signal generation unit 120. The carrier frequency selection unit 130 selects the frequency of the carrier signal, in particular, according to the distance L.

Specifically, as shown in FIG. 2A, when the distance L is shorter than the distance L1, the carrier frequency selection unit 130 selects the frequency f1 as the frequency of the carrier signal. When the distance L is equal to or greater than the distance L1 and shorter than the distance L2, the carrier frequency selection unit 130 selects the frequency f2 (<f1) as the frequency of the carrier signal. When the distance L is the distance L2 or more, the carrier frequency selection unit 130 selects the frequency f3 (<f2) as the frequency of the carrier signal in principle (exceptions will be described later).

Here, as shown in FIG. 2B, the frequencies f1 and f2 are frequencies included in a frequency band suitable for protecting the inverter 110 from the viewpoint of thermal design. On the other hand, the frequency f3 is a frequency included in a frequency band within the frequency range of the carrier signal in which the inverter 110 can be PWM-controlled and in which the influence of switching noise caused by the inverter 110 on the receiver 20 can be suitably suppressed. .. The frequency fb in FIG. 2B is the frequency at the boundary between the former frequency band and the latter frequency band. This frequency fb changes according to, for example, the specifications of the inverter 110, the characteristics of the components constituting the inverter 110, and the like.

The carrier frequency selection unit 130 may select the frequency so that the frequency of the carrier signal becomes lower as the distance L becomes longer, for example.

(motion)
The operation of the control device 100 configured as described above will be described with reference to the flowchart of FIG.

In FIG. 3, the carrier frequency selection unit 130 determines whether or not the receiver 20 is ON (step S101). When it is determined in the process of step S101 that the receiver 20 is not ON (that is, it is OFF) (step S101: No), the process is terminated. In this case, the carrier frequency selection unit 130 selects, for example, a frequency according to the operating state of the motor 11 as the frequency of the carrier signal. In this case, the process of step S101 is performed after a predetermined time (for example, several tens of milliseconds to several hundreds of milliseconds) has elapsed.

When it is determined in the process of step S101 that the receiver 20 is ON (step S101: Yes), the distance detection unit 140 acquires the position information indicating the position of the vehicle 1 (step S102). In the process of step S102, the distance L is further detected by the distance detecting unit 140. Then, the carrier frequency selection unit 130 acquires the detected distance L.

Next, the carrier frequency selection unit 130 determines whether or not the distance L is shorter than the distance L1 (step S103). When it is determined in the process of step S103 that the distance L is shorter than the distance L1 (step S103: Yes), the carrier frequency selection unit 130 sets the frequency f1 as the frequency of the carrier signal (step S104). Then, after a lapse of a predetermined time, the process of step S101 is performed (because if the vehicle 1 is traveling, the distance L changes).

When it is determined in the process of step S103 that the distance L is not shorter than the distance L1 (step S103: No), the carrier frequency selection unit 130 determines whether or not the distance L is shorter than the distance L2 (step S105). .. When it is determined in the process of step S105 that the distance L is shorter than the distance L2 (step S105: Yes), the carrier frequency selection unit 130 sets the frequency f2 as the frequency of the carrier signal (step S106). Then, after a lapse of a predetermined time, the process of step S101 is performed.

When it is determined in the process of step S105 that the distance L is not shorter than the distance L2 (step S105: No), the carrier frequency selection unit 130 tentatively selects the frequency f3 as the frequency of the carrier signal (step S107). In parallel with or before and after the process of step S107, the carrier frequency selection unit 130 acquires the battery current Ib detected by the current sensor 31 (step S108), and the inverter 110 detected by the temperature sensor 32. The temperature LT of the contained reactor is acquired (step S109).

Next, the carrier frequency selection unit 130 determines whether or not at least one of the first condition that the battery current Ib is larger than the threshold current Ibth and the second condition that the temperature LT is larger than the threshold temperature LTth is satisfied. Determination (step S110). When it is determined in the process of step S110 that at least one of the above conditions is satisfied (step S110: Yes), the carrier frequency selection unit 130 selects the frequency f2 as the frequency of the carrier signal instead of the frequency f3 (step S110: Yes). Step S111). Then, after a lapse of a predetermined time, the process of step S101 is performed. The process of step S111 corresponds to the above-mentioned exception when the distance L is the distance L2 or more.

When it is determined in the process of step S110 that neither the first condition nor the second condition is satisfied (step S110: No), the carrier frequency selection unit 130 selects the frequency f3 as the frequency of the carrier signal. do. Then, after a lapse of a predetermined time, the process of step S101 is performed.

The threshold current Ibth is a value that determines in advance whether or not the frequency of the carrier signal is set to a frequency (here, frequency f2) different from the frequency corresponding to the distance L (here, frequency f3). It is set as a fixed value or as a variable value according to some physical quantity or parameter. Such a threshold current Ib is set based on the obtained relationship between, for example, the battery current Ib and the calorific value of the reactor caused by the battery current Ib, empirically, experimentally, or by simulation. do it.

Like the threshold current Ib, the threshold temperature LTth is a value that determines whether or not the frequency of the carrier signal is set to a frequency different from the frequency corresponding to the distance L, and is set in advance as a fixed value or some physical quantity or. It is set as a variable value according to the parameter. Such a threshold temperature LTth may be set as a value smaller than the upper limit value of the allowable temperature range by a predetermined value based on, for example, an allowable temperature range based on the temperature characteristic of the reactor and a detection error of the temperature sensor 32.

(Technical effect)
According to the research of the inventor of the present application, the following matters have been found. That is, when the frequency of the carrier signal rises, the frequency characteristic of the switching noise caused by the inverter 110 changes, and the noise level increases. On the other hand, when the frequency of the carrier signal decreases, the noise level decreases, but the temperature of the reactor contained in the inverter 110 tends to increase.

The intensity of the broadcasting radio wave received by the receiver 20 becomes weaker as the vehicle 1 moves away from the base station that transmits the broadcasting radio wave. When the frequency of the carrier signal is constant, the larger the distance L between the vehicle 1 and the base station, the greater the influence of the switching noise caused by the inverter 110 on the receiver 20.

In the control device 100, when the distance L is relatively long, a frequency lower than when the distance L is relatively short is selected as the frequency of the carrier signal by the carrier frequency selection unit 130. As a result, when the distance L is relatively long, the noise level is reduced as compared with the case where the distance L is relatively short.

On the other hand, when the distance L is relatively long (in the present embodiment, when the distance L is the distance L2 or more), the first condition that the battery current Ib is larger than the threshold current Ibth and the temperature LT are the threshold temperature. On condition that at least one of the second conditions of being larger than LTth is satisfied, the carrier frequency selection unit 130 performs a frequency higher than the frequency corresponding to the distance L (frequency f3 in the present embodiment) (in the present embodiment). , Frequency f2) is selected as the frequency of the carrier signal. As a result, the temperature rise of the reactor due to the decrease in the frequency of the carrier signal is suppressed, and the noise level is reduced to some extent.

As described above, according to the control device 100, it is possible to suppress the influence of the switching noise caused by the inverter 110 on the receiver 20 and to protect the inverter 110 at the same time.

Various aspects of the invention derived from the embodiments described above will be described below.

The control device according to one aspect of the invention is a control device that controls the motor in a vehicle including a motor as a drive source, a battery as a power source for the motor, and a receiver capable of receiving radio waves for broadcasting. An inverter having one end electrically connected to the motor and the other end electrically connected to the battery, a generation means for generating a carrier signal used for controlling the inverter, and the generation means. Between the battery and the motor, a determination means for determining the frequency of the carrier signal generated by the device, a first detection means for detecting the distance between the vehicle and the facility for transmitting the broadcasting radio wave, and the battery. A second detecting means for detecting the flowing current and a third detecting means for detecting the temperature of the reactor contained in the inverter are provided, and the determining means is detected when the detected distance is long. A frequency lower than that when the distance is short is determined as the frequency of the carrier signal, and the determination means is a case where the frequency of the carrier signal corresponding to the detected distance is a first frequency lower than a predetermined frequency. When at least one of the condition that the detected current is higher than the predetermined current value and the condition that the detected temperature is higher than the predetermined temperature is satisfied, the second frequency higher than the predetermined frequency is satisfied. Is determined as the frequency of the carrier signal.

In the above-described embodiment, the "carrier signal generation unit 120" corresponds to an example of the "generation means", the "carrier frequency selection unit 130" corresponds to an example of the "determining means", and the "distance detection unit 140" corresponds to the "distance detection unit 140". The "current sensor 31" corresponds to an example of the "second detection means", and the "temperature sensor 32" corresponds to an example of the "third detection means". The "threshold current Ibth" according to the above-described embodiment corresponds to an example of "predetermined current value", the "threshold temperature TLth" corresponds to an example of "predetermined temperature", and the "frequency fb" corresponds to an example of "predetermined frequency". The "frequency f3" corresponds to an example of the "first frequency", and the "frequency f2" corresponds to an example of the "second frequency".

In the control device, when the distance detected by the first detection means (that is, the distance between the vehicle and the facility transmitting the broadcasting radio wave) is long, the carrier has a lower frequency than when the distance is short. Determined as the frequency of the signal. The longer the distance, the weaker the intensity of the broadcast radio wave received by the receiver, but if the frequency of the carrier signal decreases, the noise level caused by the inverter will be reduced, and as a result, the noise related to the receiver will be reduced. Deterioration of the level is suppressed.

However, when the frequency of the carrier signal decreases, the temperature of the reactor contained in the inverter tends to increase. Therefore, in the control device, from the viewpoint of protecting parts such as reactors, even when the frequency of the carrier signal corresponding to the above distance is the first frequency, the current detected by the second detection means is predetermined. When at least one of the condition that the current value is higher than the current value and the condition that the temperature detected by the third detection means is higher than the predetermined temperature is satisfied, the second frequency higher than the first frequency is the carrier signal. Determined as frequency. As a result, the temperature rise of the reactor is suppressed. In addition, it can be expected that the deterioration of the noise level related to the receiver will be suppressed to some extent.

As described above, according to the control device, it is possible to appropriately control the motor by suppressing the deterioration of the noise level related to the receiver and suppressing the thermal deterioration of the inverter, for example.

The present invention is not limited to the above-described embodiment, and can be appropriately modified within the scope of claims and within the scope not contrary to the gist or idea of the invention that can be read from the entire specification, and a control device accompanied by such a modification is also possible. It is also included in the technical scope of the present invention.

1 ... Vehicle, 11 ... Motor, 12 ... Battery, 20 ... Receiver, 31 ... Current sensor, 32 ... Temperature sensor, 100 ... Control device, 110 ... Inverter, 120 ... Carrier signal generator, 130 ... Carrier frequency selection unit, 140 ... Distance detector

Claims (1)

A control device for controlling a motor in a vehicle including a motor as a drive source, a battery as a power source for the motor, and a receiver capable of receiving broadcast radio waves.
An inverter with one end electrically connected to the motor and the other end electrically connected to the battery.
A generation means for generating a carrier signal used for controlling the inverter, and a generation means.
A determination means for determining the frequency of the carrier signal generated by the generation means, and a determination means.
A first detecting means for detecting the distance between the vehicle and the facility that transmits the broadcasting radio wave, and the like.
A second detecting means for detecting the current flowing between the battery and the motor,
A third detection means for detecting the temperature of the reactor contained in the inverter,
Equipped with
When the detected distance is long, the determining means determines a frequency lower than that when the detected distance is short as the frequency of the carrier signal.
The determination means is a condition that the frequency of the carrier signal corresponding to the detected distance is a first frequency lower than a predetermined frequency, and the detected current is higher than the predetermined current value, and A control device, characterized in that, when at least one of the conditions that the detected temperature is higher than a predetermined temperature is satisfied, a second frequency higher than the predetermined frequency is determined as the frequency of the carrier signal.

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