diff --git a/mms/mms_process.c b/mms/mms_process.c
index d46d51f..ee7d0b6 100644
--- a/mms/mms_process.c
+++ b/mms/mms_process.c
@@ -2058,13 +2058,28 @@ static ST_RET Write_Named_Var(LD_info_t	*LD_info,chnl_usr_t *chnl_usr,char* VarN
  *   2. 只下载最近一个完整周期内、且测点序号匹配的 .pqd 文件；
  *   3. 下载前检查 /FeProject/data/pqdif/ 下是否已有同名文件，避免重复下载。
  */
+/* Current rule:
+ * - read /PQDIF/ periodically per terminal;
+ * - parse the .pqd file's own yyyyMMdd_HHmm_period-hours tokens;
+ * - save valid files into /FeProject/data/pqdif/<ip>/;
+ * - prevent repeated downloads with /FeProject/data/pqdif/.state/<ip>.downloaded.
+ */
 #define PQDIF_REMOTE_DIR             "/PQDIF/"
 #define PQDIF_LOCAL_DIR              "/FeProject/data/pqdif"
+#define PQDIF_TMP_DIR                "/FeProject/data/pqdif/.tmp"
+#define PQDIF_STATE_DIR              "/FeProject/data/pqdif/.state"
 #define PQDIF_AUTO_INTERVAL_HOURS    2
 #define PQDIF_SCAN_INTERVAL_MS       (60 * 1000)
 #define PQDIF_MAX_DEVICE_INDEX       4096
 #define PQDIF_MAX_FETCH_PER_SCAN     32
 
+typedef struct {
+	int		cpu_digit;
+	int		period_hours;
+	time_t	start_time;
+	time_t	end_time;
+} pqdif_file_interval_t;
+
 static const char* pqdif_basename(const char* filename)
 {
 	const char* base = filename;
@@ -2120,6 +2135,147 @@ static int pqdif_use_interval_end_time(const char* dev_type)
 	return (dev_type != NULL && strcmp(dev_type, "PS_NET_PQDIF") == 0);
 }
 
+/* Parse names such as xxx_LD1_20260720_0000_24.pqd.
+ * The token before yyyyMMdd supplies the CPU digit; the last numeric token is
+ * the file period in hours, so 1h/2h/24h files share the same matcher.
+ */
+static int pqdif_is_digit_token(const char* str, int expect_len)
+{
+	int i;
+
+	if (str == NULL)
+		return FALSE;
+
+	for (i = 0; str[i] != '\0'; ++i) {
+		if (!isdigit((unsigned char)str[i]))
+			return FALSE;
+	}
+
+	return (i == expect_len);
+}
+
+static int pqdif_parse_datetime(const char* date_token, const char* time_token, time_t* out_time)
+{
+	struct tm tm_value;
+	int year;
+	int month;
+	int day;
+	int hour;
+	int min;
+
+	if (!pqdif_is_digit_token(date_token, 8) || !pqdif_is_digit_token(time_token, 4) || out_time == NULL)
+		return FALSE;
+
+	year = (date_token[0] - '0') * 1000 + (date_token[1] - '0') * 100 +
+		(date_token[2] - '0') * 10 + (date_token[3] - '0');
+	month = (date_token[4] - '0') * 10 + (date_token[5] - '0');
+	day = (date_token[6] - '0') * 10 + (date_token[7] - '0');
+	hour = (time_token[0] - '0') * 10 + (time_token[1] - '0');
+	min = (time_token[2] - '0') * 10 + (time_token[3] - '0');
+
+	if (month < 1 || month > 12 || day < 1 || day > 31 || hour < 0 || hour > 23 || min < 0 || min > 59)
+		return FALSE;
+
+	memset(&tm_value, 0, sizeof(tm_value));
+	tm_value.tm_year = year - 1900;
+	tm_value.tm_mon = month - 1;
+	tm_value.tm_mday = day;
+	tm_value.tm_hour = hour;
+	tm_value.tm_min = min;
+	tm_value.tm_sec = 0;
+	tm_value.tm_isdst = -1;
+
+	*out_time = mktime(&tm_value);
+	return (*out_time != (time_t)-1);
+}
+
+static int pqdif_parse_file_interval(const char* filename, const char* dev_type, pqdif_file_interval_t* out_info)
+{
+	char name_buf[256];
+	char* tokens[32];
+	char* token;
+	const char* base;
+	size_t len;
+	int token_count = 0;
+	int i;
+
+	if (out_info == NULL)
+		return FALSE;
+
+	memset(out_info, 0, sizeof(*out_info));
+
+	if (!pqdif_has_pqd_suffix(filename))
+		return FALSE;
+
+	base = pqdif_basename(filename);
+	len = strlen(base);
+	if (len <= 4 || len >= sizeof(name_buf))
+		return FALSE;
+
+	snprintf(name_buf, sizeof(name_buf), "%s", base);
+	name_buf[len - 4] = '\0';
+
+	token = strtok(name_buf, "_");
+	while (token != NULL && token_count < (int)(sizeof(tokens) / sizeof(tokens[0]))) {
+		tokens[token_count++] = token;
+		token = strtok(NULL, "_");
+	}
+
+	for (i = 1; i + 2 < token_count; ++i) {
+		const char* cpu_token = tokens[i - 1];
+		const char* date_token = tokens[i];
+		const char* time_token = tokens[i + 1];
+		const char* period_token = tokens[i + 2];
+		size_t cpu_len = strlen(cpu_token);
+		time_t file_time;
+		int period_hours;
+
+		if (!pqdif_is_digit_token(date_token, 8) || !pqdif_is_digit_token(time_token, 4))
+			continue;
+
+		if (cpu_len == 0 || !isdigit((unsigned char)cpu_token[cpu_len - 1]))
+			continue;
+
+		for (len = 0; period_token[len] != '\0'; ++len) {
+			if (!isdigit((unsigned char)period_token[len]))
+				break;
+		}
+		if (period_token[len] != '\0')
+			continue;
+
+		period_hours = atoi(period_token);
+		if (period_hours <= 0 || period_hours > 24 * 366)
+			continue;
+
+		if (!pqdif_parse_datetime(date_token, time_token, &file_time))
+			continue;
+
+		out_info->cpu_digit = cpu_token[cpu_len - 1] - '0';
+		out_info->period_hours = period_hours;
+
+		if (pqdif_use_interval_end_time(dev_type)) {
+			out_info->end_time = file_time;
+			out_info->start_time = file_time - period_hours * 3600;
+		}
+		else {
+			out_info->start_time = file_time;
+			out_info->end_time = file_time + period_hours * 3600;
+		}
+
+		return TRUE;
+	}
+
+	return FALSE;
+}
+
+static int pqdif_cpu_matches(int file_cpu_digit, int cpu_no)
+{
+	if (cpu_no <= 0)
+		return FALSE;
+
+	return (file_cpu_digit == (cpu_no % 10));
+}
+
 static time_t pqdif_align_interval_start(long long sec)
 {
 	time_t hour_floor;
@@ -2139,8 +2295,16 @@ static time_t pqdif_align_interval_start(long long sec)
 
 static int pqdif_match_interval(const char* filename, int cpu_no, time_t interval_start, const char* dev_type)
 {
-	time_t name_time;
-	char time_match[64];
+	pqdif_file_interval_t file_info;
+
+	if (!pqdif_parse_file_interval(filename, dev_type, &file_info))
+		return FALSE;
+
+	if (!pqdif_cpu_matches(file_info.cpu_digit, cpu_no))
+		return FALSE;
+
+	return (file_info.start_time <= interval_start && interval_start < file_info.end_time);
+#if 0
 
 	if (!pqdif_has_pqd_suffix(filename))
 		return FALSE;
@@ -2159,16 +2323,102 @@ static int pqdif_match_interval(const char* filename, int cpu_no, time_t interva
 
 	pqdif_make_time_match(cpu_no, name_time, time_match, sizeof(time_match));
 	return strstr(filename, time_match) != NULL;
+#endif
 }
 
 static int pqdif_match_recent_interval(const char* filename, int cpu_no, const char* dev_type)
 {
 	time_t now_time;
-	time_t interval_start;
+	pqdif_file_interval_t file_info;
 
 	now_time = time(NULL);
-	interval_start = pqdif_align_interval_start((long long)now_time) - PQDIF_AUTO_INTERVAL_HOURS * 3600;
-	return pqdif_match_interval(filename, cpu_no, interval_start, dev_type);
+	if (!pqdif_parse_file_interval(filename, dev_type, &file_info))
+		return FALSE;
+
+	if (!pqdif_cpu_matches(file_info.cpu_digit, cpu_no))
+		return FALSE;
+
+	return (file_info.end_time <= now_time);
+}
+
+static int pqdif_match_auto_candidate(const char* filename, int cpu_no, const char* dev_type,
+	time_t now_time, pqdif_file_interval_t* out_info)
+{
+	pqdif_file_interval_t file_info;
+
+	if (!pqdif_parse_file_interval(filename, dev_type, &file_info))
+		return FALSE;
+
+	if (!pqdif_cpu_matches(file_info.cpu_digit, cpu_no))
+		return FALSE;
+
+	if (file_info.end_time > now_time)
+		return FALSE;
+
+	if (out_info != NULL)
+		*out_info = file_info;
+
+	return TRUE;
+}
+
+static int pqdif_is_latest_auto_file(char **filenames, int filenum, const char* candidate_name,
+	int cpu_no, const char* dev_type, time_t now_time)
+{
+	pqdif_file_interval_t best_info;
+	const char *best_name = NULL;
+	int have_best = FALSE;
+	int i;
+
+	if (!pqdif_match_auto_candidate(candidate_name, cpu_no, dev_type, now_time, NULL))
+		return FALSE;
+
+	memset(&best_info, 0, sizeof(best_info));
+	for (i = 0; i < filenum; i++) {
+		const char *base_name;
+		pqdif_file_interval_t file_info;
+
+		if (filenames[i] == NULL)
+			continue;
+
+		base_name = pqdif_basename(filenames[i]);
+		if (base_name[0] == '\0')
+			continue;
+
+		if (!pqdif_match_auto_candidate(base_name, cpu_no, dev_type, now_time, &file_info))
+			continue;
+
+		if (!have_best ||
+			file_info.end_time > best_info.end_time ||
+			(file_info.end_time == best_info.end_time && file_info.start_time > best_info.start_time) ||
+			(file_info.end_time == best_info.end_time && file_info.start_time == best_info.start_time &&
+				best_name != NULL && strcmp(base_name, best_name) > 0)) {
+			have_best = TRUE;
+			best_info = file_info;
+			best_name = base_name;
+		}
+	}
+
+	return (have_best && best_name != NULL && strcmp(candidate_name, best_name) == 0);
+}
+
+static int pqdif_match_recall_range(const char* filename, int cpu_no, long long start_sec, long long end_sec,
+	const char* dev_type, pqdif_file_interval_t* out_info)
+{
+	pqdif_file_interval_t file_info;
+
+	if (!pqdif_parse_file_interval(filename, dev_type, &file_info))
+		return FALSE;
+
+	if (!pqdif_cpu_matches(file_info.cpu_digit, cpu_no))
+		return FALSE;
+
+	if ((long long)file_info.end_time <= start_sec || (long long)file_info.start_time >= end_sec)
+		return FALSE;
+
+	if (out_info != NULL)
+		*out_info = file_info;
+
+	return TRUE;
 }
 
 static int pqdif_ensure_local_dir()
@@ -2179,24 +2429,228 @@ static int pqdif_ensure_local_dir()
 
 	if (mkdir(PQDIF_LOCAL_DIR, 0777) != 0 && errno != EEXIST)
 		return SD_FAILURE;
+
+	if (mkdir(PQDIF_TMP_DIR, 0777) != 0 && errno != EEXIST)
+		return SD_FAILURE;
+
+	if (mkdir(PQDIF_STATE_DIR, 0777) != 0 && errno != EEXIST)
+		return SD_FAILURE;
 #endif
 	return SD_SUCCESS;
 }
 
-static int pqdif_local_file_exists(const char* filename)
+static void pqdif_make_ip_dir_name(const char* ip_str, char* out, size_t out_len)
 {
-	char local_file[512];
+	size_t i;
+	size_t j = 0;
+
+	if (out == NULL || out_len == 0)
+		return;
+
+	if (ip_str == NULL || ip_str[0] == '\0') {
+		snprintf(out, out_len, "unknown");
+		return;
+	}
+
+	for (i = 0; ip_str[i] != '\0' && j + 1 < out_len; ++i) {
+		unsigned char ch = (unsigned char)ip_str[i];
+
+		if (isalnum(ch) || ch == '.' || ch == '-' || ch == '_')
+			out[j++] = (char)ch;
+		else
+			out[j++] = '_';
+	}
+	out[j] = '\0';
+
+	if (out[0] == '\0')
+		snprintf(out, out_len, "unknown");
+}
+
+static void pqdif_build_device_dirs(chnl_usr_t *chnl_usr, char* local_dir, size_t local_dir_len, char* tmp_dir, size_t tmp_dir_len)
+{
+	char ip_dir[128];
+
+	pqdif_make_ip_dir_name(chnl_usr ? chnl_usr->ip_str : NULL, ip_dir, sizeof(ip_dir));
+
+	if (local_dir != NULL && local_dir_len > 0)
+		snprintf(local_dir, local_dir_len, "%s/%s", PQDIF_LOCAL_DIR, ip_dir);
+
+	if (tmp_dir != NULL && tmp_dir_len > 0)
+		snprintf(tmp_dir, tmp_dir_len, "%s/%s", PQDIF_TMP_DIR, ip_dir);
+}
+
+static int pqdif_ensure_device_dirs(chnl_usr_t *chnl_usr, char* local_dir, size_t local_dir_len, char* tmp_dir, size_t tmp_dir_len)
+{
+	pqdif_build_device_dirs(chnl_usr, local_dir, local_dir_len, tmp_dir, tmp_dir_len);
+
+	if (pqdif_ensure_local_dir() != SD_SUCCESS)
+		return SD_FAILURE;
+
+#ifdef _OS_UNIX_
+	if (local_dir == NULL || tmp_dir == NULL)
+		return SD_FAILURE;
+
+	if (mkdir(local_dir, 0777) != 0 && errno != EEXIST)
+		return SD_FAILURE;
+
+	if (mkdir(tmp_dir, 0777) != 0 && errno != EEXIST)
+		return SD_FAILURE;
+#endif
+	return SD_SUCCESS;
+}
+
+static int pqdif_copy_file(const char* src_file, const char* dst_file)
+{
+	FILE *src;
+	FILE *dst;
+	char buf[8192];
+	size_t nread;
+	int ret = SD_SUCCESS;
+
+	if (src_file == NULL || dst_file == NULL || src_file[0] == '\0' || dst_file[0] == '\0')
+		return SD_FAILURE;
+
+	src = fopen(src_file, "rb");
+	if (src == NULL)
+		return SD_FAILURE;
+
+	dst = fopen(dst_file, "wb");
+	if (dst == NULL) {
+		fclose(src);
+		return SD_FAILURE;
+	}
+
+	while ((nread = fread(buf, 1, sizeof(buf), src)) > 0) {
+		if (fwrite(buf, 1, nread, dst) != nread) {
+			ret = SD_FAILURE;
+			break;
+		}
+	}
+
+	if (ferror(src))
+		ret = SD_FAILURE;
+
+	if (fclose(dst) != 0)
+		ret = SD_FAILURE;
+
+	fclose(src);
+
+	if (ret != SD_SUCCESS)
+		remove(dst_file);
+
+	return ret;
+}
+
+static long pqdif_get_local_file_size(const char* filename)
+{
+	FILE *fp;
+	long size;
+
+	if (filename == NULL || filename[0] == '\0')
+		return -1;
+
+	fp = fopen(filename, "rb");
+	if (fp == NULL)
+		return -1;
+
+	if (fseek(fp, 0, SEEK_END) != 0) {
+		fclose(fp);
+		return -1;
+	}
+
+	size = ftell(fp);
+	fclose(fp);
+	return size;
+}
+
+/* Successful downloads are tracked outside the final data directory.  The PQDIF
+ * reader may delete /FeProject/data/pqdif/<ip>/ files after processing, so the
+ * final directory must not be used as the duplicate-download ledger.
+ */
+static void pqdif_build_state_file(chnl_usr_t *chnl_usr, char* state_file, size_t state_file_len)
+{
+	char ip_dir[128];
+
+	if (state_file == NULL || state_file_len == 0)
+		return;
+
+	pqdif_make_ip_dir_name(chnl_usr ? chnl_usr->ip_str : NULL, ip_dir, sizeof(ip_dir));
+	snprintf(state_file, state_file_len, "%s/%s.downloaded", PQDIF_STATE_DIR, ip_dir);
+}
+
+static void pqdif_strip_line_end(char* line)
+{
+	size_t len;
+
+	if (line == NULL)
+		return;
+
+	len = strlen(line);
+	while (len > 0 && (line[len - 1] == '\r' || line[len - 1] == '\n' ||
+		line[len - 1] == ' ' || line[len - 1] == '\t')) {
+		line[len - 1] = '\0';
+		len--;
+	}
+}
+
+static int pqdif_download_record_exists(chnl_usr_t *chnl_usr, const char* filename)
+{
+	char state_file[512];
+	char line[512];
+	FILE *fp;
 	const char* base = pqdif_basename(filename);
 
 	if (base[0] == '\0')
 		return FALSE;
 
-	snprintf(local_file, sizeof(local_file), "%s/%s", PQDIF_LOCAL_DIR, base);
-#ifdef _OS_UNIX_
-	return access(local_file, F_OK) == 0;
-#else
+	pqdif_build_state_file(chnl_usr, state_file, sizeof(state_file));
+	fp = fopen(state_file, "r");
+	if (fp == NULL)
+		return FALSE;
+
+	while (fgets(line, sizeof(line), fp) != NULL) {
+		pqdif_strip_line_end(line);
+		if (strcmp(line, base) == 0) {
+			fclose(fp);
+			return TRUE;
+		}
+	}
+
+	fclose(fp);
 	return FALSE;
-#endif
+}
+
+static int pqdif_record_download_success(chnl_usr_t *chnl_usr, const char* filename)
+{
+	char state_file[512];
+	FILE *fp;
+	const char* base = pqdif_basename(filename);
+	int ret = SD_SUCCESS;
+
+	if (base[0] == '\0')
+		return SD_FAILURE;
+
+	if (pqdif_download_record_exists(chnl_usr, base))
+		return SD_SUCCESS;
+
+	if (pqdif_ensure_local_dir() != SD_SUCCESS)
+		return SD_FAILURE;
+
+	pqdif_build_state_file(chnl_usr, state_file, sizeof(state_file));
+	fp = fopen(state_file, "a");
+	if (fp == NULL)
+		return SD_FAILURE;
+
+	if (fprintf(fp, "%s\n", base) < 0)
+		ret = SD_FAILURE;
+
+	if (fflush(fp) != 0)
+		ret = SD_FAILURE;
+
+	if (fclose(fp) != 0)
+		ret = SD_FAILURE;
+
+	return ret;
 }
 
 static void pqdif_build_remote_filename(const char* dir_filename, char* out, size_t out_len)
@@ -2220,7 +2674,10 @@ static void pqdif_build_remote_filename(const char* dir_filename, char* out, siz
 static int pqdif_get_file_from_device(chnl_usr_t *chnl_usr, const char *rem_filename, char *only_filename_ret, size_t only_filename_ret_len)
 {
 	int ret;
-	char loc_file_fullname[512];
+	char tmp_file_fullname[512];
+	char final_file_fullname[512];
+	char local_dir[512];
+	char tmp_dir[512];
 	char rem_file_fullname[512];
 	const char *only_filename;
 
@@ -2231,40 +2688,61 @@ static int pqdif_get_file_from_device(chnl_usr_t *chnl_usr, const char *rem_file
 	if (only_filename[0] == '\0')
 		return SD_FAILURE;
 
-	if (pqdif_ensure_local_dir() != SD_SUCCESS) {
-		echo_warn1("[PQDIF] create local dir failed: %s\n", PQDIF_LOCAL_DIR);
+	if (pqdif_ensure_device_dirs(chnl_usr, local_dir, sizeof(local_dir), tmp_dir, sizeof(tmp_dir)) != SD_SUCCESS) {
+		echo_warn2("[PQDIF] create local dir failed: local=%s tmp=%s\n", local_dir, tmp_dir);
 		return SD_FAILURE;
 	}
 
-	memset(loc_file_fullname,0,sizeof(loc_file_fullname));
+	memset(tmp_file_fullname,0,sizeof(tmp_file_fullname));
+	memset(final_file_fullname,0,sizeof(final_file_fullname));
 	memset(rem_file_fullname,0,sizeof(rem_file_fullname));
-	apr_snprintf(loc_file_fullname,sizeof(loc_file_fullname),"%s/%s",PQDIF_LOCAL_DIR,only_filename);
+	apr_snprintf(tmp_file_fullname,sizeof(tmp_file_fullname),"%s/%s",tmp_dir,only_filename);
+	apr_snprintf(final_file_fullname,sizeof(final_file_fullname),"%s/%s",local_dir,only_filename);
 	apr_snprintf(rem_file_fullname,sizeof(rem_file_fullname),"%s",rem_filename);
 
 	if (only_filename_ret != NULL && only_filename_ret_len > 0)
 		apr_snprintf(only_filename_ret,only_filename_ret_len,"%s",only_filename);
 
-	printf("[PQDIF] mms_getFile local=%s remote=%s\n", loc_file_fullname, rem_file_fullname);
+	/* Keep the same safety flow as the C# reader:
+	 * download to a temporary backup path first, remove failed/empty files,
+	 * copy to the final PQDIF directory only after validation, then remove temp.
+	 */
+	remove(tmp_file_fullname);
 
-	ret = mms_getFile(chnl_usr->net_info,loc_file_fullname,rem_file_fullname,g_pt61850app->mmsOpTimeout);
+	printf("[PQDIF] mms_getFile tmp=%s final=%s remote=%s\n",
+		tmp_file_fullname, final_file_fullname, rem_file_fullname);
+
+	ret = mms_getFile(chnl_usr->net_info,tmp_file_fullname,rem_file_fullname,g_pt61850app->mmsOpTimeout);
 	if (ret != SD_SUCCESS) {
-		echo_warn3("[PQDIF] mms_getFile failed IP=%s local=%s remote=%s\n",
-			chnl_usr->ip_str, loc_file_fullname, rem_file_fullname);
+		remove(tmp_file_fullname);
+		echo_warn3("[PQDIF] mms_getFile failed IP=%s tmp=%s remote=%s\n",
+			chnl_usr->ip_str, tmp_file_fullname, rem_file_fullname);
 		return ret;
 	}
 
-#ifdef _OS_UNIX_
-	{
-		struct stat st;
-
-		if (stat(loc_file_fullname, &st) != 0 || st.st_size <= 0) {
-			unlink(loc_file_fullname);
-			echo_warn2("[PQDIF] file is empty or invalid: %s from %s\n",
-				loc_file_fullname, rem_file_fullname);
-			return SD_FAILURE;
-		}
+	if (pqdif_get_local_file_size(tmp_file_fullname) <= 0) {
+		remove(tmp_file_fullname);
+		echo_warn2("[PQDIF] file is empty or invalid: %s from %s\n",
+			tmp_file_fullname, rem_file_fullname);
+		return SD_FAILURE;
 	}
-#endif
+
+	if (pqdif_copy_file(tmp_file_fullname, final_file_fullname) != SD_SUCCESS) {
+		remove(tmp_file_fullname);
+		echo_warn2("[PQDIF] copy validated file failed: %s -> %s\n",
+			tmp_file_fullname, final_file_fullname);
+		return SD_FAILURE;
+	}
+
+	if (pqdif_record_download_success(chnl_usr, only_filename) != SD_SUCCESS) {
+		remove(tmp_file_fullname);
+		remove(final_file_fullname);
+		echo_warn2("[PQDIF] write download record failed, remove copied file: IP=%s file=%s\n",
+			chnl_usr->ip_str, only_filename);
+		return SD_FAILURE;
+	}
+
+	remove(tmp_file_fullname);
 
 	return SD_SUCCESS;
 }
@@ -2281,8 +2759,7 @@ static apr_status_t ChannelRecallPQDIFFiles(chnl_usr_t *chnl_usr, LD_info_t *LD_
 	int			existed = 0;
 	int			missing = 0;
 	int			failed = 0;
-	time_t		interval_start;
-	time_t		interval_step;
+	int			matched = 0;
 
 	if (chnl_usr == NULL || chnl_usr->chnl == NULL || chnl_usr->chnl->ied == NULL ||
 		chnl_usr->chnl->ied->usr_ext == NULL || chnl_usr->net_info == NULL ||
@@ -2329,76 +2806,72 @@ static apr_status_t ChannelRecallPQDIFFiles(chnl_usr_t *chnl_usr, LD_info_t *LD_
 		return APR_EGENERAL;
 	}
 
-	interval_step = PQDIF_AUTO_INTERVAL_HOURS * 3600;
-	interval_start = pqdif_align_interval_start(start_sec);
+	printf("[PQDIF][RECALL] begin mp_id=%s cpuno=%d range=%lld~%lld files=%d dev_type=%s\n",
+		LD_info->mp_id, LD_info->cpuno, start_sec, end_sec, filenum, ied_usr->dev_type);
 
-	printf("[PQDIF][RECALL] begin mp_id=%s cpuno=%d range=%lld~%lld interval_start=%lld files=%d dev_type=%s\n",
-		LD_info->mp_id, LD_info->cpuno, start_sec, end_sec, (long long)interval_start,
-		filenum, ied_usr->dev_type);
+	for (file_idx = 0; file_idx < filenum; file_idx++) {
+		const char *base_name;
+		char remote_filename[256];
+		char only_filename_ret[256];
+		pqdif_file_interval_t file_info;
+		int ret_get;
 
-	while ((long long)interval_start < end_sec) {
-		int found_this_interval = FALSE;
+		if (filenames[file_idx] == NULL)
+			continue;
 
-		for (file_idx = 0; file_idx < filenum; file_idx++) {
-			const char *base_name;
-			char remote_filename[256];
-			char only_filename_ret[256];
-			int ret_get;
+		base_name = pqdif_basename(filenames[file_idx]);
+		if (base_name[0] == '\0')
+			continue;
 
-			if (filenames[file_idx] == NULL)
-				continue;
+		if (!pqdif_match_recall_range(base_name, LD_info->cpuno, start_sec, end_sec,
+			ied_usr->dev_type, &file_info))
+			continue;
 
-			base_name = pqdif_basename(filenames[file_idx]);
-			if (base_name[0] == '\0')
-				continue;
-
-			if (!pqdif_match_interval(base_name, LD_info->cpuno, interval_start, ied_usr->dev_type))
-				continue;
-
-			found_this_interval = TRUE;
-			if (pqdif_local_file_exists(base_name)) {
-				existed++;
-				printf("[PQDIF][RECALL] local file exists, skip mp_id=%s interval=%lld file=%s\n",
-					LD_info->mp_id, (long long)interval_start, base_name);
-				break;
-			}
-
-			memset(remote_filename,0,sizeof(remote_filename));
-			memset(only_filename_ret,0,sizeof(only_filename_ret));
-			pqdif_build_remote_filename(filenames[file_idx], remote_filename, sizeof(remote_filename));
-			if (remote_filename[0] == '\0') {
-				failed++;
-				break;
-			}
-
-			ret_get = pqdif_get_file_from_device(chnl_usr, remote_filename, only_filename_ret, sizeof(only_filename_ret));
-			if (ret_get == SD_SUCCESS) {
-				fetched++;
-				chnl_usr->m_LastPosRespTime = sGetMsTime();
-				printf("[PQDIF][RECALL] fetch success mp_id=%s interval=%lld remote=%s local=%s/%s\n",
-					LD_info->mp_id, (long long)interval_start, remote_filename, PQDIF_LOCAL_DIR, only_filename_ret);
-			}
-			else {
-				failed++;
-				echo_warn3("[PQDIF][RECALL] fetch failed mp_id=%s remote=%s IP=%s\n",
-					LD_info->mp_id, remote_filename, chnl_usr->ip_str);
-			}
-			break;
+		matched++;
+		if (pqdif_download_record_exists(chnl_usr, base_name)) {
+			existed++;
+			printf("[PQDIF][RECALL] download record exists, skip mp_id=%s file=%s file_range=%lld~%lld period=%d\n",
+				LD_info->mp_id, base_name, (long long)file_info.start_time,
+				(long long)file_info.end_time, file_info.period_hours);
+			continue;
 		}
 
-		if (!found_this_interval) {
-			missing++;
-			printf("[PQDIF][RECALL] no matched file mp_id=%s interval=%lld dev_type=%s\n",
-				LD_info->mp_id, (long long)interval_start, ied_usr->dev_type);
+		memset(remote_filename,0,sizeof(remote_filename));
+		memset(only_filename_ret,0,sizeof(only_filename_ret));
+		pqdif_build_remote_filename(filenames[file_idx], remote_filename, sizeof(remote_filename));
+		if (remote_filename[0] == '\0') {
+			failed++;
+			continue;
 		}
 
-		interval_start += interval_step;
+		ret_get = pqdif_get_file_from_device(chnl_usr, remote_filename, only_filename_ret, sizeof(only_filename_ret));
+		if (ret_get == SD_SUCCESS) {
+			char local_dir[512];
+
+			fetched++;
+			chnl_usr->m_LastPosRespTime = sGetMsTime();
+			pqdif_build_device_dirs(chnl_usr, local_dir, sizeof(local_dir), NULL, 0);
+			printf("[PQDIF][RECALL] fetch success mp_id=%s file_range=%lld~%lld period=%d remote=%s local=%s/%s\n",
+				LD_info->mp_id, (long long)file_info.start_time, (long long)file_info.end_time,
+				file_info.period_hours, remote_filename, local_dir, only_filename_ret);
+		}
+		else {
+			failed++;
+			echo_warn3("[PQDIF][RECALL] fetch failed mp_id=%s remote=%s IP=%s\n",
+				LD_info->mp_id, remote_filename, chnl_usr->ip_str);
+		}
 	}
 
-	printf("[PQDIF][RECALL] finish mp_id=%s fetched=%d existed=%d missing=%d failed=%d\n",
-		LD_info->mp_id, fetched, existed, missing, failed);
+	if (matched == 0) {
+		missing++;
+		printf("[PQDIF][RECALL] no matched file mp_id=%s range=%lld~%lld dev_type=%s\n",
+			LD_info->mp_id, start_sec, end_sec, ied_usr->dev_type);
+	}
 
-	if (missing > 0 || failed > 0)
+	printf("[PQDIF][RECALL] finish mp_id=%s matched=%d fetched=%d existed=%d missing=%d failed=%d\n",
+		LD_info->mp_id, matched, fetched, existed, missing, failed);
+
+	if (matched == 0 || failed > 0)
 		return APR_EGENERAL;
 
 	return APR_SUCCESS;
@@ -2463,6 +2936,7 @@ static apr_status_t ChannelCheckPQDIFFiles(chnl_usr_t *chnl_usr)
 	int				matched = 0;
 	int				scan_idx;
 	double			now_ms;
+	time_t			now_time;
 	static double	s_last_scan_ms[PQDIF_MAX_DEVICE_INDEX] = {0};
 
 	if (chnl_usr == NULL || chnl_usr->chnl == NULL || chnl_usr->chnl->ied == NULL ||
@@ -2489,6 +2963,7 @@ static apr_status_t ChannelCheckPQDIFFiles(chnl_usr_t *chnl_usr)
 		return APR_SUCCESS;
 	}
 	s_last_scan_ms[scan_idx] = now_ms;
+	now_time = time(NULL);
 
 	/* 本函数只做 PQDIF 文件获取：
 	 * 1. 从装置固定目录 /PQDIF/ 取文件列表；
@@ -2543,13 +3018,16 @@ static apr_status_t ChannelCheckPQDIFFiles(chnl_usr_t *chnl_usr)
 			 * 这里保持同样的匹配方式，不依赖厂家前缀，也兼容普通设备用
 			 * 周期开始时间命名、振兴类设备用周期结束时间命名的差异。
 			 */
-			if (!pqdif_match_recent_interval(base_name, LD_info->cpuno, ied_usr->dev_type))
+			if (!pqdif_is_latest_auto_file(filenames, filenum, base_name,
+				LD_info->cpuno, ied_usr->dev_type, now_time))
 				continue;
 
 			matched++;
-			if (pqdif_local_file_exists(base_name)) {
-				printf("[PQDIF] local file exists, skip mp_id=%s file=%s\n", LD_info->mp_id, base_name);
-				continue;
+
+			if (pqdif_download_record_exists(chnl_usr, base_name)) {
+				printf("[PQDIF] latest file already downloaded, skip mp_id=%s file=%s\n",
+					LD_info->mp_id, base_name);
+				break;
 			}
 
 			memset(remote_filename,0,sizeof(remote_filename));
@@ -2560,10 +3038,13 @@ static apr_status_t ChannelCheckPQDIFFiles(chnl_usr_t *chnl_usr)
 
 			ret_get = pqdif_get_file_from_device(chnl_usr, remote_filename, only_filename_ret, sizeof(only_filename_ret));
 			if (ret_get == SD_SUCCESS) {
+				char local_dir[512];
+
 				fetched++;
 				chnl_usr->m_LastPosRespTime = sGetMsTime();
+				pqdif_build_device_dirs(chnl_usr, local_dir, sizeof(local_dir), NULL, 0);
 				printf("[PQDIF] fetch success mp_id=%s name=%s remote=%s local=%s/%s\n",
-					LD_info->mp_id, LD_info->name, remote_filename, PQDIF_LOCAL_DIR, only_filename_ret);
+					LD_info->mp_id, LD_info->name, remote_filename, local_dir, only_filename_ret);
 			}
 			else {
 				echo_warn3("[PQDIF] fetch failed mp_id=%s remote=%s IP=%s\n",
@@ -2575,6 +3056,7 @@ static apr_status_t ChannelCheckPQDIFFiles(chnl_usr_t *chnl_usr)
 					PQDIF_MAX_FETCH_PER_SCAN, ied->id, chnl_usr->ip_str);
 				return APR_SUCCESS;
 			}
+			break;
 		}
 	}